Heating calculation

In order to most correctly determine the size of the required amount of fuel, calculate kilowatts of heating, and also calculate the greatest operating efficiency heating system provided that the agreed type of fuel is used, housing and communal services specialists created a special methodology and program for calculating heating, which makes it much easier to obtain the necessary information using previously known factors.

This technique allows you to correctly calculate heating - the right amount of fuel of any type.

And, in addition, the results obtained are an important indicator, which is certainly taken into account when calculating tariffs for housing and communal services, as well as when drawing up an estimate of the financial needs of this organization. Let us answer the question of how to correctly calculate heating based on increased indicators.

Features of the technique

This technique, which can be used using a heating calculation calculator, is regularly used to calculate the technical and economic efficiency of implementing various types of energy-saving programs, as well as when using new equipment and launching energy-efficient processes.

In order to calculate the heating of a room - calculate the heat load (hourly) in the heating system separate building, you can use the formula:

In this formula for calculating the heating of a building:

• a is a coefficient showing a possible correction for the difference in external air temperature when calculating the operating efficiency of the heating system, where to from to = -30°C, and at the same time the necessary parameter q 0 is determined;
• The indicator V (m 3) in the formula is the external volume of the heated building (it can be found in project documentation building);
• q 0 (kcal/m3 h°C) is a specific characteristic when heating a building, taking into account t o = -30°C;
• K.r acts as an infiltration coefficient, which takes into account additional characteristics such as wind force and heat flow. This indicator indicates the calculation of heating costs - this is the level of heat loss of the building due to infiltration, while heat transfer is carried out through the external enclosure, and the external air temperature applied to the entire project is taken into account.

If the building for which online heating calculations are carried out has an attic (attic floor), then the V indicator is calculated by multiplying the indicator of the horizontal section of the building (meaning the indicator obtained at the floor level of the 1st floor) by the height of the building.

In this case, the height is determined to the top point of the attic insulation. If the roof of a building is combined with an attic floor, then the heating calculation formula uses the height of the building to the midpoint of the roof. It should be noted that if there are protruding elements and niches in the building, they are not taken into account when calculating the V indicator.

Before heating is calculated, it should be taken into account that if the building has a basement or basement that also needs heating, then 40% of the area of ​​this room should be added to the V indicator.

To determine the K i.r indicator, the following formula is used:

wherein:

• g – acceleration obtained during free fall (m/s 2);
• L – height of the house;
• w 0 – according to SNiP 23-01-99 – the conditional value of the wind speed present in a given region during the heating season;

In those regions where the calculated external air temperature t 0 £ -40 is used, when creating a heating system project, before calculating the heating of the room, a heat loss of 5% should be added. This is permissible in cases where it is planned that the house will have an unheated basement. This heat loss is caused by the fact that the floor of the premises on the 1st floor will always be cold.

For stone houses, the construction of which has already been completed, the higher heat loss during the first heating period should be taken into account and certain adjustments should be made. At the same time, heating calculations based on aggregated indicators take into account the completion date of construction:

May-June - 12%;

July-August – 20%;

September – 25%;

Heating season (October-April) – 30%.

To calculate the specific heating characteristics building q 0 (kcal/m 3 h) should be calculated using the following formula:

Hot water supply

Wherein:

• a – consumption rate hot water subscriber (l/unit) per day. This indicator is approved by local authorities. If the standard is not approved, the indicator is taken from the table SNiP 2.04.01-85 (Appendix 3).
• N is the number of residents (students, workers) in the building, related to the day.
• t c – indicator of the temperature of water supplied during the heating season. If this indicator is missing, an approximate value is taken, namely t c = 5 °C.
• T – a certain period of time per day when hot water is supplied to the subscriber.
• Q t.p – indicator of heat loss in the hot water supply system. Most often, this indicator reflects the heat loss of the external circulation and supply pipelines.

To determine the average heat load of the hot water supply system during the period when the heating is turned off, calculations should be made using the formula:

• Q hm – average value level of heat load of the hot water supply system during the heating period. Unit of measurement - Gcal/h.
• b – an indicator demonstrating the degree of reduction in the hourly load in the hot water supply system during the non-heating period, compared to the same indicator during the heating period. This indicator should be determined by the city government. If the value of the indicator is not determined, the average parameter is used:
• 0.8 for housing and communal services of cities located in middle lane Russia;
• 1.2-1.5 is an indicator applicable to southern (resort) cities.

For enterprises located in any region of Russia, a single indicator is used - 1.0.

• t hs, t h - indicator of the temperature of hot water supplied to subscribers during the heating and non-heating periods.
• t cs, t c – temperature indicator tap water during the heating and non-heating periods. If this indicator is unknown, you can use averaged data - tcs = 15 °C, tc = 5 °C.

When designing heating and ventilation of automobile service enterprises, the requirements of SNiP 2.04.05-86 and these VSN must be observed

Estimated air temperatures during the cold period in industrial buildings should be taken:

in rolling stock storage rooms - + 5С

in warehouses - + 10С

in other rooms - according to the requirements of Table 1 GOST 12.1.005-86

Category Ib includes work performed while sitting or involving walking and accompanied by some physical stress (a number of professions in communications enterprises, controllers, foremen).

Category IIa includes work associated with constant walking, moving small (up to 1 kg) products or objects in a standing or sitting position and requiring little physical stress (a number of professions in spinning and weaving, mechanical assembly shops).

Category IIb includes work associated with walking and moving loads weighing up to 10 kg and accompanied by moderate physical stress (a number of professions in mechanical engineering and metallurgy).

Category III includes work associated with constant movement, moving and carrying significant (more than 10 kg) weights and requiring significant physical effort (a number of professions involving manual operations in metallurgical, mechanical engineering, and mining enterprises).

Heating of storage rooms, maintenance and repair stations of rolling stock, as a rule, should be provided by air, combined with fresh ventilation.

Heating with local heating devices with a smooth surface without fins is allowed in car storage rooms in one-story buildings with a volume of up to 10,000 m 3 inclusive, as well as in car storage rooms in multi-storey buildings regardless of volume.

4.4. In storage rooms, maintenance and repair stations of rolling stock, emergency heating should be provided using:

Supply ventilation switched to recirculation during non-working hours;

Heating and recirculation units;

Air-thermal curtains;

Local heating devices with a smooth surface without ribbing.

4.5. The heat requirement for heating rolling stock entering the premises should be taken in the amount of 0.029 watts per hour per kg of mass in running order per one degree difference in the temperatures of the external and internal air.

4.6. External gates of storage rooms, maintenance and repair stations of rolling stock should be equipped with air-thermal curtains in areas with an average design outside air temperature of 15 °C, and lower under the following conditions:

When there are five or more entries or exits per hour per gate in the premises of rolling stock maintenance and repair posts;

When maintenance posts are located at a distance of 4 meters or less from the external gate;

When there are 20 or more entries and exits per hour per gate in the storage area for rolling stock, except for passenger cars owned by citizens;

When storing 50 or more passenger cars belonging to citizens in the premises.

Thermal air curtains must be switched on and off automatically.

4.7. To ensure the required air conditions in storage rooms, maintenance and repair stations of rolling stock, general supply and exhaust ventilation with mechanical drive should be provided, taking into account the operating mode of the enterprise and the amount of harmful emissions installed in the technological part of the project.

4.8. In rolling stock storage rooms, including ramps, air removal should be provided equally from the upper and lower zones of the room; The supply of fresh air to the room should, as a rule, be carried out concentrated along the passages.

4.10. In the premises of rolling stock maintenance and repair stations, air removal by general ventilation systems should be provided from the upper and lower zones equally, taking into account exhaust from inspection ditches, and supply supply air- dispersed into the working area and into inspection ditches, as well as into pits connecting inspection ditches, and into tunnels provided for exiting travel ditches.

The temperature of the supply air into inspection ditches, pits and tunnels during the cold season should not be lower than +16 °C and not higher than +25 °C.

Amount of supply and exhaust air per one cubic meter the volume of inspection ditches, pits and tunnels should be taken based on their tenfold air exchange

4.12. In industrial premises connected through doors and gates without a vestibule with storage rooms and maintenance and repair stations, the volume of supply air should be taken with a coefficient of 1.05. At the same time, in storage rooms and maintenance and repair stations, the volume of supply air should be correspondingly reduced.

4.13. In the premises of maintenance and repair stations of rolling stock at posts associated with the operation of vehicle engines, local suction should be provided.

The amount of air removed from operating engines, depending on their power, should be taken as follows:

up to 90 kW (120 hp) inclusive - 350 m 3 / h

St. 90 to 130 kW (120 to 180 hp) - 500 m 3 /h

St. 130 to 175 kW (180 to 240 hp) - 650 m 3 /h

St. 175 kW (240 hp) - 800 m 3 /h

The number of cars connected to the system of local suction with mechanical removal is not limited.

When placing no more than five posts for maintenance and repair of vehicles in a room, it is allowed to design local suction with natural removal for vehicles with a power of no more than 130 kW (180 hp)

The amount of engine exhaust gases escaping into the room should be taken as follows:

with hose suction - 10%

with open suction - 25%

4.16. Reception devices for supply ventilation systems must be located at a distance of at least 12 meters from the gate with the number of entries and exits of more than 10 cars per hour.

When the number of entries and exits is less than 10 cars per hour, the receiving devices of the supply ventilation systems can be located at a distance of at least one meter from the gate.

Air exchange in a car wash bay is calculated based on excess moisture. Air exchange in rooms with moisture release is determined by the formula, m3/hour: L=Lw,z+(W–1.2(dw,z–din)):1.2(dl–din), Lw,z - air flow rate removed local suction, m3/hour;

W - excess moisture in the room, g/hour;

tн - initial temperature of flowing water С;

tk - final temperature of flowing water С;

r – latent heat of evaporation, amounting to ~585 kcal/kg According to the technological process, 3 cars are washed within an hour. It takes 15 minutes to wash the car and 5 minutes to dry it. The amount of water used is 510 l/hour. The initial water temperature is +40С, the final temperature is +16С. For calculation, we assume that 10% of the water used in the technology remains on the surface of the car and on the floor. Air moisture content is determined using i – d diagrams. For supply air, we take the parameters for the most unfavorable period in terms of moisture content - the transition period: air temperature - + 8С, specific enthalpy - 22.5 kJ/kg. Based on this: W = 0.1 (510 x (40 - 16) : 585) = 2.092 kg/hour = 2092 g/hour. Lvl. =2092: 1.2 (9 –5.5) = 500 m3/h.

SNiP 2.01.57-85

ADAPTATION OF CAR WASHING AND CLEANING ROOMS FOR SPECIAL TREATMENT OF ROLLING STOCK

6.1. When designing the adaptation of new or reconstruction of existing motor transport enterprises, centralized vehicle maintenance bases, vehicle service stations, vehicle washing and cleaning posts should be provided with travel passes.

6.2. Special processing of rolling stock should be carried out on production lines and drive-through posts in car washing and cleaning rooms. At existing enterprises, dead-end car washing and cleaning stations should not be adapted for special processing of rolling stock. When designing special processing of rolling stock, it is necessary to take into account the sequence of operations:

control of contamination of rolling stock (if it is contaminated with radioactive substances);

cleaning and washing of external and internal surfaces of rolling stock (if it is contaminated with radioactive substances);

application of neutralizing substances to the surface of the rolling stock (during degassing and disinfection);

exposure (during disinfection) of applied substances to the surface of rolling stock;

washing off (removing) disinfectants;

re-monitoring the degree of contamination of the rolling stock radioactive substances and, if necessary, repeating decontamination;

lubrication of surfaces of parts and tools made of easily corrosive materials.

6.3. When specially processing rolling stock, at least two sequentially located work stations should be used.

The work station of the “clean” zone, intended for repeated control of contamination and for lubrication, may be located separately from the “dirty” zone in an adjacent room or outside the building - on the territory of the enterprise.

Work stations of the “dirty” and “clean” zones, located in the same room, should be separated by partitions with openings for the passage of cars. Openings must be equipped with waterproof curtains.

6.4. In one room it is allowed to place two or more parallel flows for special processing of rolling stock, while the posts of “dirty” zones of parallel flows must be isolated from one another by partitions or screens with a height of at least 2.4 m.

The distances between the sides of the rolling stock and the screens must be no less than: passenger cars - 1.2 m; trucks and buses - 1.5 m.

The distances between the end sides of the rolling stock, partitions, curtains or external gates should be taken in accordance with the standards.

6.5. At posts for special processing of rolling stock in the “dirty” area, it is necessary to install work tables with a metal or plastic coating, as well as metal containers with neutralizing solutions for special processing of components, parts and tools removed from vehicles.

In the “clean” area, provision should be made for the installation of work tables for re-inspection and lubrication of removed units, parts and tools.

6.6. Washing equipment and work tables located in the “dirty” and “clean” areas should be provided with a supply of cold and hot water, as well as compressed air, through a mixer.

The water temperature for washing rolling stock using mechanized installations is not standardized. When washing with a hose manually, the water temperature should be 20 - 40 °C.

6.7. Work stations in the “dirty” and “clean” zones for work in the lower part of the rolling stock must be equipped with inspection ditches, overpasses or lifts. The dimensions of the working area of ​​the inspection ditches should be taken in accordance with table. 6.

Table 6

Steps in the inspection ditch should be provided in the end part from the side of vehicle entrances to work stations without the construction of tunnels (passages).

6.8. The throughput capacity of the section for special processing of rolling stock is given in the mandatory Appendix 1.

Approximate layouts and equipment of work stations in a room for two parallel production lines and one drive-through station are given in the recommended Appendix 2.

6.9. In the same building with a room for special processing of rolling stock, it is necessary to provide separate rooms for storing special processing equipment and materials. The area of ​​the room should be taken depending on the throughput of the area for disinfection of the composition, but not less than 8 m 2. The entrance to the premises should be from a “clean” area. The room must be equipped with shelving.

6.10. Room for service personnel and the sanitary checkpoint, as a rule, should be located in the same building with special processing posts for rolling stock.

The room for service personnel must have an entrance from the “clean” area.

For sanitary checkpoints, it is allowed to adapt sanitary facilities (with two shower nets or more) located in other buildings of the enterprise.

6.11. The requirements for the sanitary checkpoint for servicing personnel, rolling stock drivers and accompanying persons, for the composition and size of its premises are similar to the requirements set out in section 3.

6.12. The finishing of walls and partitions, as well as the installation of floors in rooms for special processing of rolling stock, must comply with the requirements of technological design standards , as well as the requirements of paragraph. 1.5 real standards.

The floors of the premises for special processing of rolling stock must have a slope of 0.02 towards the inspection ditches, the floors of which must have a slope towards the outlet Wastewater.

6.13. In special processing rooms for rolling stock, rooms for service personnel and in the warehouse for contaminated clothing, watering taps should be provided for washing floors.

6.14. Wastewater from premises adapted for special treatment of rolling stock must be supplied to treatment facilities for recycling water supply. Used in usual time When sanitizing transport, treatment facilities must be switched to a direct-flow scheme without changing the treatment scheme.

The residence time of wastewater in treatment facilities must be at least 30 minutes. After treatment, wastewater must be discharged into the domestic or storm sewer system.

Sludge or oils from treatment facilities should be transported to places approved by the local sanitary and epidemiological station.

6.15. Supply and exhaust ventilation must provide an hourly air exchange rate of at least 10 in the “dirty” zone of production premises and sanitary passage. Supply air should be supplied only to the “clean” zone.

The exhaust should be concentrated from the upper part of the room, with 2/3 from the “dirty” zone and 1/3 of the volume of sucked air from the “clean” zone.

When the work stations of the “clean” zone are located separately from the “dirty” zone (outside the building - on the territory of the enterprise), supply air should be supplied to the work stations of the “dirty” zone.

The exhaust air volume should be 20% greater than the supply air volume.

ANNEX 1Mandatory

This mandatory appendix provides data to SNiP 2.01.57-85 “Adaptation of public utility facilities for sanitary treatment of people, special treatment of clothing and rolling stock of vehicles,” developed to replace SN 490-77.

3.2 Heating calculation

Calculation of heat for heating an industrial premises is calculated using the formula:

Q t = V * q * (t in – t n), (3.5)

where V is the estimated volume of the room; V =120 m³

q – specific fuel consumption rate per 1 m3; q =2.5

t in – air temperature in the room; t in = 18ºС

t n – minimum outside air temperature. t n = -35ºС

Q t = 120 * 2.5 * (18 - (- 35)) = 15900 J/hour.

3.3 Calculation of ventilation

The required approximate air exchange in the premises can be determined through the air exchange rate using the formula:

where L is air exchange in the room;

V – volume of the room;

K – air exchange rate, K=3

L = 120 * 3 = 360 m 3 /hour.

We select a centrifugal fan of the VR series No. 2, electric motor type AOA-21-4.

n - rotation speed – 1.5 thousand rpm;

L in – fan capacity – 400 m 3 /hour;

Нв – pressure created by the fan – 25 kg/m2;

η in – coefficient useful action fan – 0.48;

η p - transmission efficiency – 0.8.

The choice of electric motor based on installed power is calculated using the formula:

N dv = (1.2/1.5) * ------- (3.7)

3600 * 102 * η in* η p

N dv = (1.2/1.5) * --------- = 0.091 kW

3600 * 102 * 0,48 * 0,8

We accept power N dv = 0.1 kW

Bibliography.

1. SNiP 2.04.05-86 Heating, ventilation and air conditioning

SNiP 21 - 02 - 99* "Car parking"

VSN 01-89 "Car service enterprises" section 4.

GOST 12.1.005-88 "General sanitary and hygienic requirements for air in the working area"

ONTP-01-91 "All-Union standards for technological design of automobile transport enterprises" Section 3.

SNiP 2.01.57-85ADAPTATION OF MUNICIPAL SERVICE FACILITIESPURPOSE FOR SANITARY TREATMENT OF PEOPLE,SPECIAL PROCESSING OF CLOTHING AND MOBILECOMPOSITION OF MOTOR TRANSPORT section 6.

GOST 12.1.005-88 section 1.

GENERAL SANITARY AND HYGIENIC REQUIREMENTS FOR AIR IN THE WORKING AREA

SNiP 2.04.05-91*

SNiP 2.09.04-87*

SNiP 41-01-2003 section 7.

1. Sp 12.13130.2009 Determination of categories of premises, buildings and outdoor installations according to explosion and fire hazard (with Change n 1)

2. SNiP II-g.7-62 Heating, ventilation and air conditioning. Design standards

13. SNiP 23 – 05 – 95. Natural and artificial lighting. –M.: State Unitary Enterprise TsPP, 1999

L.1 Supply air flow L, m 3 / h, for the ventilation and air conditioning system should be determined by calculation and take the greater of the costs required to ensure:

a) sanitary and hygienic standards in accordance with L.2;

b) fire and explosion safety standards in accordance with L.Z.

L.2 Air flow should be determined separately for the warm and cold periods of the year and transition conditions, taking the larger of the values ​​obtained from formulas (L.1) - (L.7) (with a density of supply and exhaust air equal to 1.2 kg /m 3):

a) by excess sensible heat:

When simultaneously releasing several harmful substances having the effect of summation of action, air exchange should be determined by summing up the air flow rates calculated for each of these substances:

a) for excess moisture (water vapor):

c) according to the normalized air exchange rate:

d) according to the standardized specific flow rate of supply air:

In formulas (L.1) - (L.7):

L wz- consumption of air removed from the serviced or working area of ​​the premises by local suction systems and for technological needs, m 3 /h;

Q, Q hf - excess sensible and total heat flows into the room, W; c - heat capacity of air equal to 1.2 kJ/(m 3 ∙°C);

t wz. - temperature of air removed by local suction systems in the serviced or working area of ​​the room and for technological needs, °C;

t 1 - temperature of air removed from the room outside the serviced or working area, °C;

t in- temperature of air supplied to the room, °C, determined in accordance with L.6;

W - excess moisture in the room, g/h;

d wz- moisture content of air removed from the serviced or working area of ​​the premises by local suction systems, and for technological needs, g/kg;

d 1 - moisture content of air removed from the premises outside the serviced or working area, g/kg;

d in- moisture content of air supplied to the room, g/kg;

I wz- specific enthalpy of air removed from the serviced or working area of ​​the premises by local suction systems, and for technological needs, kJ/kg;

I 1 - specific enthalpy of air removed from the room outside the serviced or working area, kJ/kg;

I in- specific enthalpy of air supplied to the room, kJ/kg, determined taking into account the temperature increase in accordance with L.6;

m ro- consumption of each of the harmful or explosive substances entering the air in the room, mg/h;

q wz , q 1 - concentration of a harmful or explosive substance in the air removed from the serviced or working area of ​​the room and beyond, respectively, mg/m 3 ;

q in- concentration of harmful or explosive substance in the air supplied to the room, mg/m3;

V R- volume of the room, m3; for rooms with a height of 6 m or more should be taken

A- area of ​​the room, m2;

N- number of people (visitors), workplaces, pieces of equipment;

n- normalized air exchange rate, h -1;

k- normalized supply air flow per 1 m 2 of room floor, m 3 / (h∙m 2);

m- standardized specific consumption supply air per 1 person, m 3 /h, per 1 workplace, per 1 visitor or piece of equipment.

Air parameters t wz , d wz , I wz should be taken equal to the design parameters in the serviced or working area of ​​the premises according to Section 5 of these standards, a q wz- equal to the maximum permissible concentration in the working area of ​​the room.

L.3 Air flow to ensure explosion and fire safety standards should be determined using formula (L.2).

Moreover, in formula (L.2) q wz And q 1 , should be replaced by 0.1 q g, mg/m 3 (where q g- lower concentration limit of flame propagation through gas, steam and dust-air mixtures).

L.4 Air flow L he, m 3 / h, for air heating, not combined with ventilation, should be determined by the formula

Where Q he – heat flow for space heating, W

t he- the temperature of heated air, °C, supplied to the room is determined by calculation.

L.5 Air flow L mt from intermittently operating ventilation systems with rated capacity L d, m 3 / h, is based on n, min, interrupted by system operation for 1 hour according to the formula

b) with outside air cooled by circulating water through an adiabatic cycle, reducing its temperature by ∆t 1 °C:

d) with outside air cooled by circulating water (see subparagraph “b”) and local additional humidification (see subparagraph “c”):

Where R- total fan pressure, Pa;

t ext- outside air temperature, °C.

On this website tab we will try to help you choose the right parts of the system for your home. Any node has an important role. Therefore, the selection of installation parts must be planned technically correctly. The heating system has thermostats, a connection system, fasteners, air vents, an expansion tank, batteries, manifolds, boiler pipes, and pressure-increasing pumps. Installation of apartment heating includes various elements.

To make heating calculations, you need to calculate how much heat is required to maintain optimal temperature in the cold season. This value will be equal to the heat that the apartment loses when minimum temperatures ah (about 30 degrees).

When taking into account heat loss, attention is paid to the level of thermal insulation of windows and doors, the thickness of the walls and the material of the building itself. If the calculation of the apartment heating system is ultimately 10 kW, this value will determine not only the boiler power, but also the number of radiators.

The higher the energy efficiency of an apartment, the less energy is required to heat it. To achieve this result, you should replace the windows with modern energy-saving ones, pay attention doorways and ventilation system, insulate the walls inside or outside the apartment.

The degree of heating of the apartment depends on the movement of the coolant. Its speed may depend on several factors:

• Pipe section. The larger the diameter, the faster the coolant will move.
• Curves and length of the section. According to a complex pattern, the liquid circulates more slowly
• Pipe material. When comparing iron and plastic, then latest version there will be less resistance, which means the coolant speed will be higher.

All these indicators determine hydraulic resistance.

Calculation of heating in industrial buildings

The most common option is water heating. It has many schemes that should be taken into account according to individual characteristics buildings. The main calculations are hydraulic and thermal. High-quality heating pipes and heating mains will help you avoid many problems in the future. This type of heating is most suitable for residential and administrative types of buildings and offices.

The air type is based on the operation of a heat generator that heats the air to circulate it throughout the system. Calculation of an air heating system is the main step for creating effective system. It is advisable to use in shopping centers, industrial and production buildings.

Direct calculation of the heating system of an industrial building requires an approach qualified specialists and attention, otherwise many negative consequences may occur.

Common mistakes and how to fix them

The calculation of the heating system itself is an important and complex stage in the development of heating. Special computer programs help specialists perform all calculations. However, errors may still occur.

One of the common problems is the incorrect calculation of the thermal power of the heating system or the lack thereof. In addition to the high cost of radiators, their high power will cause the entire system to become unprofitable. That is, the heating will work more than necessary, wasting fuel on it. Heat the room will burn a lot of oxygen and require regular ventilation to reduce its indicator.

Completed: art. gr.VI-12

Tsivaty I.I.

Dnepropetrovsk 2011

1 . Ventilation as a means of protection in industrial air environment premises

The task of ventilation is to ensure air purity and specified meteorological conditions in production premises. Ventilation is achieved by removing polluted or heated air from a room and introducing fresh air into it.

Depending on the site of action, ventilation can be general exchange or local. The action of general exchange ventilation is based on the dilution of contaminated, heated, humid air rooms with fresh air to the maximum acceptable standards. This ventilation system is most often used in cases where harmful substances, heat, and moisture are released evenly throughout the room. With such ventilation, the required parameters are maintained air environment throughout the entire room.

Air exchange in a room can be significantly reduced if harmful substances are captured at the points of their release. To this end technological equipment, which is a source of release of harmful substances, is equipped with special devices from which polluted air is sucked out. This type of ventilation is called local exhaust. Local ventilation Compared to general exchange, it requires significantly lower costs for device and operation.

Natural ventilation

Air exchange during natural ventilation occurs due to the difference in temperature between the air in the room and the outside air, as well as as a result of the action of wind. Natural ventilation can be unorganized and organized. With unorganized ventilation, the intake and removal of air occurs through the density and pores of external fences (infiltration), through windows, vents, and special openings (ventilation). Organized natural ventilation carried out by aeration and deflectors, and can be adjusted.

Aeration is carried out in cold shops due to wind pressure, and in hot shops due to the combined and separate action of gravitational and wind pressure. IN summer time fresh air enters the room through lower openings located at a small height from the floor (1-1.5 m), and is removed through openings in the building's skylight.

Mechanical ventilation

In systems mechanical ventilation Air movement is carried out by fans and, in some cases, ejectors. Forced ventilation. Supply ventilation installations usually consist of the following elements: an air intake device for taking in clean air; air ducts through which air is supplied to the room; filters for air purification from dust; air heaters for heating air; fan; supply nozzles; control devices that are installed in the air intake device and on the branches of the air ducts. Exhaust ventilation. Exhaust ventilation installations include: exhaust openings or nozzles; fan; air ducts; device for purifying air from dust and gases; a device for releasing air, which should be located ? 1.5 m above the roof ridge. When the exhaust system is operating fresh air enters the room through leaks in the enclosing structures. In some cases, this circumstance is a serious drawback of this ventilation system, since an unorganized influx of cold air (drafts) can cause colds. Supply and exhaust ventilation. In this system, air is supplied to the room by supply ventilation and removed by exhaust ventilation, operating simultaneously.

Local ventilation

Local ventilation can be supply or exhaust. Local forced ventilation serves to create the required air conditions in a limited area of ​​the production premises. Local supply ventilation installations include: air showers and oases, air and air-thermal curtains. Air showering is used in hot shops at workplaces under the influence of a radiant heat flow with an intensity of 350 W/m or more. An air shower is a stream of air directed at the worker. The blowing speed is 1-3.5 m/s depending on the intensity of irradiation. The effectiveness of showering units increases when water is sprayed in a stream of air.

Air oases are part production area, which is separated on all sides by light movable partitions and filled with air that is colder and cleaner than the air in the room. Air and air-thermal curtains are installed to protect people from being chilled by cold air penetrating through the gate. There are two types of curtains: air curtains with air supply without heating and air-thermal curtains with heating of the supplied air in heaters.

The operation of the curtains is based on the fact that the air supplied to the gate exits through a special air duct with a slot at a certain angle with high speed(up to 10-15 m/s) towards the incoming cold flow and mixes with it. The resulting mixture of warmer air enters the workplace or (if the heating is insufficient) is deflected away from them. When the curtains operate, additional resistance is created to the passage of cold air through the gate.

Local exhaust ventilation. Its use is based on the capture and removal of harmful substances directly at the source of their formation. Local exhaust ventilation devices are made in the form of shelters or local suction. Shelters with suction are characterized by the fact that the source of harmful emissions is located inside them.

They can be made as shelters - casings that completely or partially enclose equipment (fume hoods, display cases, cabins and chambers). A vacuum is created inside the shelters, as a result of which harmful substances cannot enter the indoor air. This method of preventing the release of harmful substances in a room is called aspiration.

Aspiration systems are usually blocked with starting devices of process equipment so that harmful substances are sucked out not only at the point of their release, but also at the moment of formation.

Complete shelter of machines and mechanisms that emit harmful substances, the most advanced and effective method preventing their release into the indoor air. It is important, even at the design stage, to develop technological equipment in such a way that ventilation devices would be organically included in the overall design, without interfering with the technological process and at the same time completely solving sanitary and hygienic problems.

Protective and dust-removing casings are installed on machines where the processing of materials is accompanied by the release of dust and the flying off of large particles that can cause injury. These are grinding, roughing, polishing, sharpening machines metal, woodworking machines, etc.

Fume hoods are widely used in thermal and galvanic processing of metals, painting, hanging and packaging of bulk materials, and in various operations involving the release of harmful gases and vapors.

Cabins and chambers are containers of a certain volume, inside of which work is carried out related to the release of harmful substances (sandblasting and shot blasting, painting work, etc.). Exhaust hoods are used to localize harmful substances rising upward, namely during heat - and moisture releases.

Suction panels are used in cases where the application exhaust hoods It is unacceptable due to the entry of harmful substances into the respiratory organs of workers. An effective local suction is the Chernoberezhsky panel, used in operations such as gas welding, soldering, etc.

Dust and gas receivers and funnels are used for soldering and welding work. They are located in close proximity to the soldering or welding site. Onboard suctions. When etching metals and applying electroplating, vapors of acids and alkalis are released from the open surface of the baths; during galvanizing, copper plating, silver plating - extremely harmful hydrogen cyanide; during chrome plating - chromium oxide, etc.

To localize these harmful substances, side suctions are used, which are slot-like air ducts 40-100 mm wide, installed along the periphery of the baths.

2. Initial data for design

heat gain exhaust supply ventilation

· name of the object - woodworking shop;

· option - B;

· construction area - Odessa;

· room height -10 m;

Availability of machines:

1 end CPA - 1.9 kW;

2 Planing SP30-І 4-sided - 25.8 kW;

3 Prireznoy PDK-4-2 - 14.8 kW;

4 Thicknesser single-sided CP6-6- 9.5 kW;

5 Jointer SF4-4 - 3.5 kW;

6 Tenoner 2-sided ШД-15-3 - 28.7 kW;

7 Tenoner one-sided ШОІО-А- 11.2 kW;

8 For drilling and sealing knots SVSA-2-3.5 kW;

9 Band saw - 5.9 kW;

10 Horizontal drilling - 5.9 kW;

11 Drilling and grooving machine SVP-2 - 3.5 kW;

12 Thicknesser single-sided CP12-2 - 33.7 kW;

13 Grinding 3-cylinder SHPATS 12-2- 30.7 kW;

14 Bench - drilling - 1.4 kW;

15 For selecting sockets for C-4 loops - 4.4 kW;

16 For selecting sockets for S-7 locks - 3.3 kW;

17 Chain-forming DSA - 6.2 kW;

18 Universal Ts-6 - 7.8 kW;

Expert opinion

Fedorov Maxim Olegovich

Industrial premises differ significantly from residential apartments in their size and volume. This is the fundamental difference between industrial ventilation systems and domestic systems. Options for heating spacious non-residential buildings exclude the use of convection methods, which are quite effective for heating housing.

The large size of production workshops, the complexity of the configuration, the presence of many devices, units or machines that allocate space thermal energy, will disrupt the convection process. It is based on the natural process of rising warm layers of air; the circulation of such flows does not tolerate even small interventions. Any draft, hot air from an electric motor or machine, will direct the flow in the other direction. In industrial workshops and warehouses there are large technological openings that can stop the operation of heating systems low power and sustainability.

In addition, convection methods do not provide uniform heating of the air, which is important for production premises. Large areas require the same air temperature at all points in the room, otherwise there will be difficulties for people to work and flow production processes. Therefore, for industrial premises specific heating methods are required, capable of providing the correct microclimate, appropriate.

Industrial heating systems

Among the most preferred heating methods industrial premises includes:

• infrared

• centralized

• zonal

Centralized systems

Centralized systems are created to ensure maximum uniform heating of all areas of the workshop. This can be important when there are no specific workplaces or the need for constant movement of people throughout the entire workshop area.

Zone systems

Zonal heating systems create areas with a comfortable microclimate in workplaces without completely covering the workshop area. This option makes it possible to save money by not wasting resources and thermal energy on ballast heating of unused or unvisited areas of the workshop. At the same time, the technological process must not be disrupted; the air temperature must meet the technological requirements.

Electric heating

Expert opinion

Heating and ventilation engineer RSV

Fedorov Maxim Olegovich

Important! It should immediately be noted that heating with electricity as the main method of heating practically not used due to its high cost.

Electric heat guns or air heaters are used as temporary or local heat sources. For example, for production repair work installed in an unheated room heat gun, allowing the repair team to work in comfortable conditions that allow them to obtain required quality work. Electric heaters as temporary heat sources are the most popular, as they do not require coolant. They only need to be connected to the network, after which they immediately begin to generate thermal energy on their own. Wherein, The serviced areas are quite small.

Air heating

Expert opinion

Heating and ventilation engineer RSV

Fedorov Maxim Olegovich

Air heating of industrial buildings is the most attractive type of heating.

It allows you to heat large rooms, regardless of their configuration. The distribution of air flows occurs in a controlled manner, the temperature and composition of the air are flexibly regulated. The operating principle is to heat the supply air using gas burners, electric or water heaters. Hot air using a fan and an air duct system, it is transported to production premises and released at the most convenient points, ensuring maximum uniformity of heating. Air heating systems have high maintainability, they are safe and allow you to fully ensure the microclimate in production premises.

Infrared heating

Expert opinion

Heating and ventilation engineer RSV

Fedorov Maxim Olegovich

Infrared heating - one of the newest, which appeared relatively recently, heating methods production premises. Its essence is to use infrared rays to heat all surfaces located in the path of the rays.

Typically the panels are located under the ceiling, radiating from top to bottom. This heats up the floor, various objects, and to some extent the walls.

Expert opinion

Heating and ventilation engineer RSV

Fedorov Maxim Olegovich

Important! This is the peculiarity of the method - It is not the air that is heated, but the objects located in the room.

For more efficient distribution of IR rays, the panels are equipped with reflectors that direct the flow of rays in the desired direction. The method of heating with infrared rays is effective and economical, but is dependent on the availability of electricity.

Advantages and disadvantages

Electric heating

Heating systems used to heat private homes or industrial buildings have their own strengths and weak sides. So, advantages electrical methods heating are:

• absence of intermediate materials (coolant). Electrical appliances themselves generate thermal energy

• high maintainability devices. All elements can be quickly replaced in case of failure without any specific repair work

• an electrically heated system can be very Flexibly and precisely adjustable. At the same time, no complex complexes are required; control is carried out using standard blocks

Infrared heating

Infrared systems have advantages:

• efficiency, efficiency

• oxygen is not burned, air humidity that is comfortable for humans is maintained

• installation such a system is enough simple and accessible for self-execution

• system No worries about voltage surges, which allows you to maintain the indoor microclimate even when connected to an unstable power supply network

• The technique is intended primarily for local, spot heating. Using it to create an even microclimate in large workshops it is irrational

• complexity of system calculation, the need for precise selection of suitable devices

Air heating

Air heating is considered the most in a convenient way heating industrial and residential premises. This is expressed in the following benefits:

• ability uniform heating of large workshops or premises of any size

• the system can be reconstructed, its power can be increased if necessary without complete dismantling

• air heating most safe to use and installation

• system has low inertia and can quickly change operating modes

• exists many options

• dependence on heating source

• addiction depending on availability connection to the electricity network

• upon failure system temperature the room is very falls quickly

Creating a heating system project

Expert opinion

Heating and ventilation engineer RSV

Fedorov Maxim Olegovich

Designing air heating is not an easy task. To solve it, it is necessary to clarify a number of factors, self-determination which may be difficult. RSV company specialists can make a preliminary one for you free of charge premises based on GREERS equipment.

The choice of one or another type of heating system is made by comparing the climatic conditions of the region, the size of the building, the height of the ceilings, the features of the intended technological process, location of workplaces. In addition, when choosing, they are guided by the cost-effectiveness of the heating method and the possibility of using it without extra costs.

The system is calculated by determining heat losses and selecting equipment that matches them in terms of power. To eliminate the possibility of errors SNiP must be used, which sets out all the requirements for heating systems and gives the coefficients necessary for calculations.

SNiP 41-01-2008

HEATING, VENTILATION AND AIR CONDITIONING

ADOPTED AND ENTERED INTO EFFECT from 01/01/2008 by decree of 2008. INSTEAD SNiP 41-01-2003

Heating system installation

Expert opinion

Heating and ventilation engineer RSV

Fedorov Maxim Olegovich

Important! Installation work are manufactured in strict accordance with the design and SNiP requirements.

Air ducts are an important element of the system, which provide transportation of gas-air mixtures. They are installed in each building or room according to an individual scheme. The size, cross-section, and shape of the air ducts play an important role during installation, since to connect the fan, adapters are needed that connect the inlet or outlet pipe of the device to the air duct system. Without high-quality adapters, it will not be possible to create a tight and efficient connection.

In accordance with the selected type of system, installations are carried out. electrical cables, is done pipe layout for coolant circulation. The equipment is installed, all necessary connections and connections are made. All work is carried out in compliance with safety requirements. The system is started in the minimum operating mode, with a gradual increase in design power.

Useful video

Create a heating system in own home or even in a city apartment - an extremely responsible occupation. It would be completely unreasonable to purchase boiler equipment, as they say, “by eye,” that is, without taking into account all the features of the housing. In this case, it is quite possible that you will end up in two extremes: either the boiler power will not be enough - the equipment will work “to the fullest”, without pauses, but still not give the expected result, or, on the contrary, an overly expensive device will be purchased, the capabilities of which will remain completely unchanged. unclaimed.

But that's not all. It is not enough to correctly purchase the necessary heating boiler - it is very important to optimally select and correctly arrange heat exchange devices in the premises - radiators, convectors or “warm floors”. And again, relying only on your intuition or the “good advice” of your neighbors is not the most reasonable option. In a word, it’s impossible to do without certain calculations.

Of course, ideally, such thermal calculations should be carried out by appropriate specialists, but this often costs a lot of money. Isn't it fun to try to do it yourself? This publication will show in detail how heating is calculated based on the area of ​​the room, taking into account many important nuances. By analogy, it will be possible to perform, built into this page, it will help to perform the necessary calculations. The technique cannot be called completely “sinless”, however, it still allows you to obtain results with a completely acceptable degree of accuracy.

The simplest calculation methods

In order for the heating system to create comfortable living conditions during the cold season, it must cope with two main tasks. These functions are closely related to each other, and their division is very conditional.

• The first is maintaining optimal level air temperature in the entire volume of the heated room. Of course, the temperature level may vary somewhat with altitude, but this difference should not be significant. An average of +20 °C is considered quite comfortable conditions - this is the temperature that is usually taken as the initial one in thermal calculations.

In other words, the heating system must be able to warm up a certain volume of air.

If we approach it with complete accuracy, then for separate rooms V residential buildings standards for the required microclimate have been established - they are defined by GOST 30494-96. An excerpt from this document is in the table below:

• The second is compensation of heat losses through building structural elements.

The most important “enemy” of the heating system is heat loss through building structures

Alas, heat loss is the most serious “rival” of any heating system. They can be reduced to a certain minimum, but even with the highest quality thermal insulation it is not yet possible to completely get rid of them. Thermal energy leaks occur in all directions - their approximate distribution is shown in the table:

Naturally, in order to cope with such tasks, the heating system must have a certain thermal power, and this potential must not only correspond common needs buildings (apartments), but also to be correctly distributed among the premises, in accordance with their area and a number of other important factors.

Usually the calculation is carried out in the direction “from small to large”. Simply put, the required amount of thermal energy is calculated for each heated room, the obtained values ​​are summed up, approximately 10% of the reserve is added (so that the equipment does not work at the limit of its capabilities) - and the result will show how much power the heating boiler is needed. And the values ​​​​for each room will become the starting point for calculating the required number of radiators.

The most simplified and most frequently used method in a non-professional environment is to adopt a norm of 100 W of thermal energy per square meter of area:

The most primitive way of calculating is the ratio of 100 W/m²

Q = S× 100

Q– required heating power for the room;

S– room area (m²);

100 — specific power per unit area (W/m²).

For example, a room 3.2 × 5.5 m

S= 3.2 × 5.5 = 17.6 m²

Q= 17.6 × 100 = 1760 W ≈ 1.8 kW

The method is obviously very simple, but very imperfect. It is worth mentioning right away that it is conditionally applicable only at a standard ceiling height - approximately 2.7 m (acceptable - in the range from 2.5 to 3.0 m). From this point of view, the calculation will be more accurate not from the area, but from the volume of the room.

It is clear that in this case the specific power value is calculated per cubic meter. It is taken equal to 41 W/m³ for reinforced concrete panel house, or 34 W/m³ - in brick or made of other materials.

Q = S × h× 41 (or 34)

h– ceiling height (m);

41 or 34 – specific power per unit volume (W/m³).

For example, the same room, in a panel house, with a ceiling height of 3.2 m:

Q= 17.6 × 3.2 × 41 = 2309 W ≈ 2.3 kW

The result is more accurate, since it already takes into account not only all the linear dimensions of the room, but even, to a certain extent, the features of the walls.

But still, it is still far from real accuracy - many nuances are “outside the brackets”. How to perform calculations closer to real conditions is in the next section of the publication.

You may be interested in information about what they are

Carrying out calculations of the required thermal power taking into account the characteristics of the premises

The calculation algorithms discussed above can be useful for an initial “estimate,” but you should still rely on them completely with great caution. Even to a person who does not understand anything about building heating engineering, the indicated average values ​​may certainly seem dubious - they cannot be equal, say, for Krasnodar region and for the Arkhangelsk region. In addition, the room is different: one is located on the corner of the house, that is, it has two external walls ki, and the other is protected from heat loss by other rooms on three sides. In addition, the room may have one or more windows, both small and very large, sometimes even panoramic. And the windows themselves may differ in the material of manufacture and other design features. And this is far from full list– it’s just that such features are visible even to the naked eye.

In a word, there are quite a lot of nuances that affect the heat loss of each specific room, and it is better not to be lazy, but to carry out a more thorough calculation. Believe me, using the method proposed in the article, this will not be so difficult.

General principles and calculation formula

The calculations will be based on the same ratio: 100 W per 1 square meter. But the formula itself is “overgrown” with a considerable number of various correction factors.

Q = (S × 100) × a × b× c × d × e × f × g × h × i × j × k × l × m

The Latin letters denoting the coefficients are taken completely arbitrarily, in alphabetical order, and have no relation to any quantities standardly accepted in physics. The meaning of each coefficient will be discussed separately.

• “a” is a coefficient that takes into account the number of external walls in a particular room.

Obviously, the more external walls there are in a room, the larger the area through which heat losses. In addition, the presence of two or more external walls also means corners - extremely vulnerable places from the point of view of the formation of “cold bridges”. Coefficient “a” will correct for this specific feature of the room.

The coefficient is taken equal to:

— external walls No (interior space): a = 0.8;

- external wall one: a = 1.0;

— external walls two: a = 1.2;

— external walls three: a = 1.4.

• “b” is a coefficient that takes into account the location of the external walls of the room relative to the cardinal directions.

You might be interested in information about what types of

Even on the coldest winter days, solar energy still has an impact on the temperature balance in the building. It is quite natural that the side of the house that faces south receives some heat from the sun's rays, and heat loss through it is lower.

But walls and windows facing north “never see” the Sun. The eastern part of the house, although it “catches” the morning sun’s rays, still does not receive any effective heating from them.

Based on this, we introduce the coefficient “b”:

- the outer walls of the room face North or East: b = 1.1;

- the external walls of the room are oriented towards South or West: b = 1.0.

• “c” is a coefficient that takes into account the location of the room relative to the winter “wind rose”

Perhaps this amendment is not so mandatory for houses located on areas protected from winds. But sometimes the prevailing winter winds can make their own “hard adjustments” to the thermal balance of a building. Naturally, the windward side, that is, “exposed” to the wind, will lose significantly more body compared to the leeward, opposite side.

Based on the results of long-term weather observations in any region, a so-called “wind rose” is compiled - graphic diagram, showing the prevailing wind directions in winter and summer. This information can be obtained from your local weather service. However, many residents themselves, without meteorologists, know very well where the winds predominantly blow in winter, and from which side of the house the deepest snowdrifts usually sweep.

If you want to carry out calculations with higher accuracy, you can include the correction factor “c” in the formula, taking it equal to:

- windward side of the house: c = 1.2;

- leeward walls of the house: c = 1.0;

- walls located parallel to the wind direction: c = 1.1.

• “d” is a correction factor that takes into account the climatic conditions of the region where the house was built

Naturally, the amount of heat loss through all building structures will greatly depend on the level of winter temperatures. It is quite clear that during the winter the thermometer readings “dance” in a certain range, but for each region there is an average indicator of the most low temperatures, characteristic of the coldest five-day period of the year (usually this is characteristic of January). For example, below is a map diagram of the territory of Russia, on which approximate values ​​are shown in colors.

Usually this value is easy to clarify in the regional weather service, but you can, in principle, rely on your own observations.

So, the coefficient “d”, which takes into account the climate characteristics of the region, for our calculations is taken equal to:

— from – 35 °C and below: d = 1.5;

— from – 30 °С to – 34 °С: d = 1.3;

— from – 25 °С to – 29 °С: d = 1.2;

— from – 20 °С to – 24 °С: d = 1.1;

— from – 15 °С to – 19 °С: d = 1.0;

— from – 10 °С to – 14 °С: d = 0.9;

- no colder - 10 °C: d = 0.7.

• “e” is a coefficient that takes into account the degree of insulation of external walls.

The total value of heat losses of a building is directly related to the degree of insulation of all building structures. One of the “leaders” in heat loss are walls. Therefore, the value of thermal power required to maintain comfortable conditions living indoors depends on the quality of their thermal insulation.

The value of the coefficient for our calculations can be taken as follows:

— external walls do not have insulation: e = 1.27;

- average degree of insulation - walls made of two bricks or their surface thermal insulation is provided with other insulation materials: e = 1.0;

— insulation was carried out with high quality, based on thermal engineering calculations: e = 0.85.

Below in the course of this publication, recommendations will be given on how to determine the degree of insulation of walls and other building structures.

• coefficient "f" - correction for ceiling heights

Ceilings, especially in private homes, can have different heights. Therefore, the thermal power to warm up a particular room of the same area will also differ in this parameter.

It would not be a big mistake to accept the following values ​​for the correction factor “f”:

— ceiling heights up to 2.7 m: f = 1.0;

— flow height from 2.8 to 3.0 m: f = 1.05;

- ceiling heights from 3.1 to 3.5 m: f = 1.1;

— ceiling heights from 3.6 to 4.0 m: f = 1.15;

- ceiling height more than 4.1 m: f = 1.2.

• « g" is a coefficient that takes into account the type of floor or room located under the ceiling.

As shown above, the floor is one of the significant sources of heat loss. This means that it is necessary to make some adjustments to account for this feature of a particular room. The correction factor “g” can be taken equal to:

- cold floor on the ground or above an unheated room (for example, a basement or basement): g= 1,4 ;

- insulated floor on the ground or above an unheated room: g= 1,2 ;

— the heated room is located below: g= 1,0 .

• « h" is a coefficient that takes into account the type of room located above.

The air heated by the heating system always rises, and if the ceiling in the room is cold, then increased heat loss is inevitable, which will require an increase in the required heating power. Let us introduce the coefficient “h”, which takes into account this feature of the calculated room:

— the “cold” attic is located on top: h = 1,0 ;

— there is an insulated attic or other insulated room on top: h = 0,9 ;

— any heated room is located on top: h = 0,8 .

• « i" - coefficient taking into account the design features of windows

Windows are one of the “main routes” for heat flow. Naturally, much in this matter depends on the quality of the window structure itself. Old wooden frames, which were previously universally installed in all houses, are significantly inferior in terms of their thermal insulation to modern multi-chamber systems with double-glazed windows.

Without words it is clear that the thermal insulation qualities of these windows differ significantly

But there is no complete uniformity between PVH windows. For example, a two-chamber double-glazed window (with three glasses) will be much “warmer” than a single-chamber one.

This means that it is necessary to enter a certain coefficient “i”, taking into account the type of windows installed in the room:

- standard wooden windows with conventional double glazing: i = 1,27 ;

- modern window systems with single-chamber double-glazed windows: i = 1,0 ;

— modern window systems with two-chamber or three-chamber double-glazed windows, including those with argon filling: i = 0,85 .

• « j" - correction factor for the total glazing area of ​​the room

Whatever quality windows No matter how they were, it will still not be possible to completely avoid heat loss through them. But it’s quite clear that you can’t compare a small window with panoramic glazing covering almost the entire wall.

First you need to find the ratio of the areas of all the windows in the room and the room itself:

x = ∑SOK /SP

∑ SOK– total area of ​​windows in the room;

SP– area of ​​the room.

Depending on the obtained value, the correction factor “j” is determined:

— x = 0 ÷ 0.1 →j = 0,8 ;

— x = 0.11 ÷ 0.2 →j = 0,9 ;

— x = 0.21 ÷ 0.3 →j = 1,0 ;

— x = 0.31 ÷ 0.4 →j = 1,1 ;

— x = 0.41 ÷ 0.5 →j = 1,2 ;

• « k" - coefficient that corrects for the presence of an entrance door

A door to the street or to an unheated balcony is always an additional “loophole” for the cold

A door to the street or to an open balcony can make adjustments to the thermal balance of the room - each opening is accompanied by the penetration of a considerable volume of cold air into the room. Therefore, it makes sense to take into account its presence - for this we introduce the coefficient “k”, which we take equal to:

- no door: k = 1,0 ;

- one door to the street or to the balcony: k = 1,3 ;

- two doors to the street or balcony: k = 1,7 .

• « l" - possible amendments to the heating radiator connection diagram

Perhaps this may seem like an insignificant detail to some, but still, why not immediately take into account the planned connection diagram for the heating radiators. The fact is that their heat transfer, and therefore their participation in maintaining a certain temperature balance in the room, changes quite noticeably when different types insertion of supply and return pipes.

Illustration	Radiator insert type	The value of the coefficient "l"
	Diagonal connection: supply from above, return from below	l = 1.0
	Connection on one side: supply from above, return from below	l = 1.03
	Two-way connection: both supply and return from below	l = 1.13
	Diagonal connection: supply from below, return from above	l = 1.25
	Connection on one side: supply from below, return from above	l = 1.28
	One-way connection, both supply and return from below	l = 1.28

• « m" - correction factor for the peculiarities of the installation location of heating radiators

And finally, the last coefficient, which is also related to the peculiarities of connecting heating radiators. It is probably clear that if the battery is installed openly and is not blocked by anything from above or from the front, then it will give maximum heat transfer. However, such an installation is not always possible - more often the radiators are partially hidden by window sills. Other options are also possible. In addition, some owners, trying to fit heating elements into the created interior ensemble, hide them completely or partially with decorative screens - this also significantly affects the thermal output.

If there are certain “outlines” of how and where radiators will be mounted, this can also be taken into account when making calculations by introducing a special coefficient “m”:

So, the calculation formula is clear. Surely, some of the readers will immediately grab their head - they say, it’s too complicated and cumbersome. However, if you approach the matter systematically and in an orderly manner, then there is no trace of complexity.

Any good homeowner must have a detailed graphic plan their “possessions” with marked dimensions, and usually oriented to the cardinal points. Climatic features region is easy to determine. All that remains is to walk through all the rooms with a tape measure and clarify some of the nuances for each room. Features of housing - “vertical proximity” above and below, the location of the entrance doors, the proposed or existing installation scheme for heating radiators - no one except the owners knows better.

It is recommended to immediately create a worksheet where you can enter all the necessary data for each room. The result of the calculations will also be entered into it. Well, the calculations themselves will be helped by the built-in calculator, which already contains all the coefficients and ratios mentioned above.

If some data could not be obtained, then you can, of course, not take them into account, but in this case the calculator “by default” will calculate the result taking into account the least favorable conditions.

Can be seen with an example. We have a house plan (taken completely arbitrary).

A region with minimum temperatures ranging from -20 ÷ 25 °C. Predominance of winter winds = northeast. The house is one-story, with an insulated attic. Insulated floors on the ground. The optimal diagonal connection of radiators that will be installed under the window sills has been selected.

Let's create a table something like this:

Then, using the calculator below, we make calculations for each room (already taking into account the 10% reserve). It won't take much time using the recommended app. After this, all that remains is to sum up the obtained values ​​for each room - this will be the required total power of the heating system.

The result for each room, by the way, will help you choose the right number of heating radiators - all that remains is to divide by the specific thermal power of one section and round up.