Temperature graph of the ventilation system. Temperature chart for supplying coolant to the heating system

When autumn confidently walks across the country, snow flies beyond the Arctic Circle, and in the Urals night temperatures stay below 8 degrees, then the word form “heating season” sounds appropriate. People recall past winters and try to figure out the normal temperature of the coolant in the heating system.

Prudent owners of individual buildings carefully revise the valves and nozzles of the boilers. Residents apartment building by October 1, they are waiting, like Santa Claus, a plumber from a management company. The ruler of valves and valves brings warmth, and with it - joy, fun and confidence in the future.

The Gigacalorie Path

Megacities sparkle with high-rise buildings. A cloud of renovation hangs over the capital. Outback prays on five-story buildings. Until demolished, the house has a calorie supply system.

Heating of an economy-class apartment building is carried out through centralized system heat supply. The pipes are included in basement buildings. The supply of heat carrier is regulated by inlet valves, after which water enters the mud collectors, and from there it is distributed through risers, and from them it is supplied to batteries and radiators that heat housing.

The number of gate valves correlates with the number of risers. While doing repair work in a single apartment, it is possible to turn off one vertical, and not the whole house.

The spent liquid partially leaves through the return pipe, and partially is supplied to the hot water supply network.

degrees here and there

Water for the heating configuration is prepared at a CHP plant or in a boiler house. The water temperature standards in the heating system are prescribed in building regulations Oh: the component must be heated to 130-150 °C.

The supply is calculated taking into account the parameters of the outside air. So, for the South Ural region, minus 32 degrees is taken into account.

To prevent the liquid from boiling, it must be supplied to the network under a pressure of 6-10 kgf. But this is a theory. In fact, most networks operate at 95-110 ° C, since the network pipes of most settlements are worn out and high pressure tear them up like a heating pad.

An extensible concept is the norm. The temperature in the apartment is never equal to the primary indicator of the heat carrier. Here it performs an energy-saving function elevator unit- jumper between the direct and return pipe. The norms for the temperature of the coolant in the heating system on the return in winter allow the preservation of heat at a level of 60 ° C.

The liquid from the straight pipe enters the elevator nozzle, mixes with return water and again goes into the house network for heating. The carrier temperature is lowered by mixing the return flow. What affects the calculation of the amount of heat consumed by residential and utility rooms.

Hot gone

Temperature hot water on sanitary rules at the points of analysis should lie in the range of 60-75 ° C.

In the network, the coolant is supplied from the pipe:

• in winter - from the reverse, so as not to scald users with boiling water;
• in summer - with a straight line, since in summer the carrier is heated no higher than 75 ° C.

A temperature chart is drawn up. Average daily temperature return water should not exceed the schedule by more than 5% at night and 3% during the day.

Parameters of distributing elements

One of the details of warming a home is a riser through which the coolant enters the battery or radiator from the temperature norms of the coolant in the heating system require heating in the riser in winter time in the range of 70-90 °C. In fact, the degrees depend on the output parameters of the CHP or boiler house. In the summer, when hot water is needed only for washing and showering, the range moves to the range of 40-60 ° C.

Observant people may notice that in a neighboring apartment, the heating elements are hotter or colder than in his own.

The reason for the temperature difference in the heating riser is the way the hot water is distributed.

In a single-pipe design, the heat carrier can be distributed:

• above; then the temperature is upper floors higher than on the bottom;
• from below, then the picture changes to the opposite - it is hotter from below.

In a two-pipe system, the degree is the same throughout, theoretically 90 ° C in the forward direction and 70 ° C in the opposite direction.

Warm like a battery

Suppose that the structures of the central network are reliably insulated along the entire route, the wind does not walk through the attics, stairwells and basements, the doors and windows in the apartments are insulated by conscientious owners.

We assume that the coolant in the riser complies with the building regulations. It remains to find out what is the norm for the temperature of the heating batteries in the apartment. The indicator takes into account:

• outdoor air parameters and time of day;
• the location of the apartment in terms of the house;
• residential or utility room in the apartment.

Therefore, attention: it is important, not what is the degree of the heater, but what is the degree of air in the room.

Happy in corner rooms the thermometer should show at least 20 ° C, and 18 ° C is allowed in centrally located rooms.

At night, air in the dwelling is allowed to be 17 ° C and 15 ° C, respectively.

Theory of linguistics

The name "battery" is household, denoting a number of identical items. In relation to the heating of housing, this is a series of heating sections.

The temperature standards of heating batteries allow heating no higher than 90 ° C. According to the rules, parts heated above 75 ° C are protected. This does not mean that they need to be sheathed with plywood or bricked. Usually they put a lattice fence that does not interfere with air circulation.

Cast iron, aluminum and bimetallic devices are common.

Consumer choice: cast iron or aluminum

Aesthetics cast iron radiators- a parable in the language. They require periodic painting, as regulations require that the work surface be smooth and allow dust and dirt to be easily removed.

A dirty coating forms on the rough inner surface of the sections, which reduces the heat transfer of the device. But the technical parameters cast iron products on high:

• little susceptible to water corrosion, can be used for more than 45 years;
• they have a high thermal power per 1 section, therefore they are compact;
• they are inert in heat transfer, therefore they smooth out temperature fluctuations in the room well.

Another type of radiators is made of aluminum. Lightweight construction, painted in the factory, does not require painting, easy to clean.

But there is a drawback that overshadows the advantages - corrosion in aquatic environment. Certainly, inner surface heaters are insulated with plastic to avoid contact of aluminum with water. But the film may be damaged, then it will begin chemical reaction with the release of hydrogen, when creating overpressure gas aluminum appliance may burst.

The temperature standards of heating radiators are subject to the same rules as batteries: it is not so much heating that matters metal object how much air heating in the room.

In order for the air to warm up well, there must be sufficient heat removal from working surface heating structure. Therefore, it is strongly not recommended to increase the aesthetics of the room with shields in front of the heating device.

Stairwell heating

Since we are talking about apartment building, then it should be mentioned stairwells. The norms for the temperature of the coolant in the heating system state: the degree measure on the sites should not fall below 12 ° C.

Of course, the discipline of the tenants requires that the doors be closed tightly. entrance group, do not leave the transoms of stair windows open, keep the glass intact and promptly report any problems to the management company. If the management company does not take timely measures to insulate the points of probable heat loss and maintain the temperature regime in the house, an application for recalculation of the cost of services will help.

Changes in heating design

Replacement of existing heating appliances in the apartment is produced with the obligatory coordination with the management company. Unauthorized change in the elements of warming radiation can disrupt the thermal and hydraulic balance of the structure.

The heating season will begin, a change in the temperature regime in other apartments and sites will be recorded. Technical inspection premises will reveal unauthorized changes in the types of heating devices, their number and size. The chain is inevitable: conflict - trial - fine.

So the situation is resolved like this:

• if not old ones are replaced with new radiators of the same size, then this is done without additional approvals; the only thing to apply to the Criminal Code is to turn off the riser for the duration of the repair;
• if new products differ significantly from those installed during construction, then it is useful to interact with the management company.

Heat meters

Let us recall once again that the heat supply network of an apartment building is equipped with heat energy metering units, which record both the consumed gigacalories and the cubic capacity of water passed through the house line.

In order not to be surprised by bills containing unrealistic amounts for heat at degrees in the apartment below the norm, before heating season check with the management company whether the metering device is in working order, whether the verification schedule has been violated.

Hi all! The calculation of the heating temperature graph begins with the choice of the control method. In order to choose a control method, it is necessary to know the ratio Qav.dhw/Qot. In this formula, Qav.gvs is the average value of heat consumption for hot water supply of all consumers, Qot is the total calculated load on heating of heat energy consumers of the district, town, city for which we calculate the temperature schedule.

Qav.gvs we find from the formula Qav.gvs = Qmax.gvs / Kch. In this formula, Qmax.DHW is the total calculated load on the DHW of the district, town, city for which the temperature graph is calculated. Kch is the coefficient of hourly unevenness, in general it is correct to calculate it on the basis of actual data. If the ratio Qav.DHW/Qfrom is less than 0.15, then central quality control according to the heating load should be used. That is, the temperature graph of the central quality regulation for heating load. In the vast majority of cases, such a schedule is used for consumers of thermal energy.

Let's calculate the temperature graph 130/70°C. The temperatures of the direct and return network water in the settlement-winter mode are: 130°C and 70°C, the water temperature at the hot water supply tg = 65°C. To build a temperature graph for direct and return network water, it is customary to consider the following characteristic modes: settlement-winter mode, mode at a temperature of return network water equal to 65 ° C, mode at a design outdoor air temperature for ventilation, mode at the break point of the temperature graph, mode at temperature outside air equal to 8°C. To calculate T1 and T2, we use the following formulas:

Т1 = tin + Δtр x Õˆ0.8 + (δtр – 0.5 x υр) x Õ;

T2 = tin + Δtr x Õ ˆ0.8— 0.5 x υр x Õ;

where tin is the design air temperature in the room, tin = 20 ˚С;

Õ - relative heating load

Õ = tin – tn/ tin – t r.o;

where tn is the outdoor air temperature,
Δtр is the design temperature head during heat transfer from heating devices.

Δtр = (95+70)/2 - 20 = 62.5 ˚С.

δtr is the temperature difference between the direct and return network water in the settlement - winter mode.
δtр = 130 - 70 = 60 °С;

υр - the difference between the water temperatures of the heater at the inlet and outlet in the settlement - winter mode.
υр = 95 - 70 = 25 °С.

We start the calculation.

1. For the settlement-winter regime, the figures are known: tо = -43 °С, T1 = 130 °С, T2 = 70 °С.

2. Mode, at a return network water temperature of 65 °C. We substitute the known parameters in the above formulas and get:

T1 = 20 + 62.5 x Õ ˆ0.8+ (60 – 0.5 x 25) x Õ = 20 + 62.5 x Õ ˆ0.8+ 47.5 x Õ,

T2 = 20 + 62.5 x Õ ˆ0.8– 12.5xÕ,

The return temperature T2 for this mode is 65 C, hence: 65 = 20 + 62.5 x Õ ˆ0.8– 12.5 x Õ, we determine Õ by the method of successive approximations. Õ = 0.869. Then T1 \u003d 65 + 60 x 0.869 \u003d 117.14 ° C.
The outdoor temperature will be in this case: tn \u003d tin - Õ x (tin - tо) \u003d 20 - 0.869 x (20- (-43)) \u003d - 34.75 ° С.

3. Mode when tn = tvent = -30 °С:
Õot = (20- (-30))/(20- (-43)) = 50/63 = 0.794
T1 \u003d 20 + 62.5 x 0.794 ˆ0.8+ 47.05 x 0.794 \u003d 109.67 ° C
T2 \u003d T1 - 60 x Õ \u003d 109.67 - 60 x 0.794 \u003d 62.03 ° C.

4. Mode when Т1 = 65 °С (temperature curve break).
65 = 20 + 62.5 x ˆ0.8+ 47.5 x Õ, we determine Õ by the method of successive approximations. Õ = 0.3628.

T2 \u003d 65 - 60 x 0.3628 \u003d 43.23 ° С
In this case, the outdoor air temperature tn = 20 - 0.3628 x (20- (-43)) = -2.86 ° С.

5. Mode when tn = 8 °С.
Õot \u003d (20-8) / (20- (-43)) \u003d 0.1905. Taking into account the cutoff of the temperature graph for hot water supply, we accept Т1 = 65 °С. The temperature T2 in the return pipeline in the range from +8 ° С to the break point of the graph is calculated by the formula:

where t1’, t2’ are the temperatures of the direct and return network water, excluding cutoff at the DHW.
T2 \u003d 65 - (65 - 8) / (45.64 - 8) x (45.63 - 34.21) \u003d 47.7 ° C.

On this, we consider the calculation of the temperature graph for characteristic modes to be completed. Other temperatures of the supply and return network water for the outdoor air temperature range are calculated in the same way.

The normative water temperature in the heating system depends on the air temperature. Therefore, the temperature schedule for the supply of coolant to the heating system is calculated in accordance with weather conditions. In the article we will talk about the requirements of SNiP for the operation of the heating system for objects for various purposes.

from the article you will learn:

In order to economically and rationally use energy resources in the heating system, the heat supply is tied to the air temperature. The dependence of the water temperature in the pipes and the air outside the window is displayed as a graph. The main task of such calculations is to maintain comfortable conditions for residents in apartments. For this, the air temperature should be about + 20 ... + 22ºС.

The temperature of the coolant in the heating system

The stronger the frost, the faster the living quarters heated from the inside lose heat. To compensate for the increased heat loss, the temperature of the water in the heating system increases.

The calculations use normative indicator temperature. It is calculated according to special technique and included in the governing documents. This figure is based on the average temperature of the 5 coldest days of the year. For calculation, 8 coldest winters are taken for 50- summer period.

Why is the drawing up of a temperature schedule for the supply of coolant to the heating system happening in this way? The main thing here is to be ready for the most severe frosts that happen every few years. Climatic conditions in a particular region can change over several decades. This will be taken into account when recalculating the schedule.

The value of the average daily temperature is also important for calculating the margin of safety of heating systems. By understanding the ultimate load, you can accurately calculate the characteristics necessary pipelines, stop valves and other elements. This saves on the creation of communications. Given the scale of construction for urban heating systems, the amount of savings will be quite large.

The temperature in the apartment directly depends on how much the coolant is heated in the pipes. In addition, other factors also matter here:

• air temperature outside the window;
• wind speed. With strong wind loads, heat losses through doorways and windows increase;
• the quality of sealing joints on the walls, as well as the general condition of the decoration and insulation of the facade.

Building codes change as technology advances. This is reflected, among other things, in the indicators in the coolant temperature graph, depending on outdoor temperature. If the premises retain heat better, then energy resources can be spent less.

Developers in modern conditions more carefully approach the thermal insulation of facades, foundations, basements and roofs. This increases the value of objects. However, along with the growth of construction costs are reduced. The overpayment at the construction stage pays off over time and gives good savings.

The heating of the premises is directly affected not even by how hot the water in the pipes is. The main thing here is the temperature of the heating radiators. It is usually in the range of + 70 ... + 90ºС.

Several factors affect battery heating.

1. Air temperature.

2. Features of the heating system. The indicator indicated in the temperature chart for supplying coolant to the heating system depends on its type. AT single pipe systems heating of water up to + 105ºС is considered normal. Two-pipe heating due to better circulation gives a higher heat transfer. This allows you to reduce the temperature to + 95ºС. Moreover, if at the inlet the water needs to be heated, respectively, to + 105ºС and + 95ºС, then at the outlet its temperature in both cases should be at the level of + 70ºС.

So that the coolant does not boil when heated above + 100ºС, it is supplied to the pipelines under pressure. Theoretically, it can be quite high. This should provide a large supply of heat. However, in practice, not all networks allow water to be supplied under high pressure due to their deterioration. As a result, the temperature drops, and during severe frosts there may be a lack of heat in apartments and other heated premises.

3. The direction of the water supply to the radiators. At top wiring the difference is 2ºС, at the bottom - 3ºС.

4. Type of heaters used. Radiators and convectors differ in the amount of heat they give off, which means that they must work in different temperature conditions. Better performance heat transfer from radiators.

At the same time, the amount of heat released is affected, among other things, by the temperature of the outdoor air. It is she who is the determining factor in the temperature schedule for supplying coolant to the heating system.

When the water temperature is +95ºС, we are talking about the coolant at the entrance to the dwelling. Given the heat loss during transportation, the boiler room should heat it much more.

In order to supply water of the required temperature to the heating pipes in the apartments, a special equipment. It mixes hot water from the boiler room with the one that comes from the return.

Temperature chart for supplying coolant to the heating system

The graph shows what the water temperature should be at the entrance to the dwelling and at the exit from it, depending on the street temperature.

The presented table will help to easily determine the degree of heating of the coolant in the central heating system.

Representatives of utilities and resource-supplying organizations measure the water temperature using a thermometer. The 5th and 6th columns indicate the figures for the pipeline through which hot coolant. 7 column - for the return.

The first three columns indicate fever- these are indicators for heat generating organizations. These figures are given without taking into account heat losses that occur during the transportation of the coolant.

temperature graph the supply of coolant to the heating system is needed not only by resource-supplying organizations. If the actual temperature differs from the standard one, consumers have reasons to recalculate the cost of the service. In their complaints, they indicate how warm the air in the apartments is. This is the easiest parameter to measure. Inspecting authorities can already track the temperature of the coolant, and if it does not comply with the schedule, force the resource supplying organization to perform its duties.

A reason for complaints appears if the air in the apartment cools below the following values:

• in the corner rooms in the daytime - below + 20ºС;
• in the central rooms in the daytime - below + 18ºС;
• in corner rooms at night - below +17ºС;
• in the central rooms at night - below +15ºС.

SNiP

Requirements for the operation of heating systems are fixed in SNiP 41-01-2003. Much attention in this document is given to security issues. In the case of heating, the heated coolant carries a potential hazard, which is why its temperature for residential and public buildings limited. It, as a rule, does not exceed + 95ºС.

If the water in the internal pipelines of the heating system is heated above + 100ºС, then the following safety measures are provided for at such facilities:

• heating pipes are laid in special mines. In the event of a breakthrough, the coolant will remain in these reinforced channels and will not be a source of danger to people;
• pipelines in high-rise buildings have special structural elements or devices that do not allow water to boil.

If the building has heating made of polymer pipes, then the temperature of the coolant should not exceed + 90ºС.

We have already mentioned above that in addition to the temperature schedule for supplying coolant to the heating system, responsible organizations need to monitor how hot the accessible elements of heating devices are. These rules are also given in SNiP. Permissible temperatures vary depending on the purpose of the room.

First of all, everything here is determined by the same security rules. For example, in children's and medical institutions allowable temperatures are minimal. AT in public places and there are usually no special restrictions for them at various production facilities.

Surface of heating radiators general rules should not be heated above +90ºС. If this figure is exceeded, Negative consequences. They consist, first of all, in the burning of paint on batteries, as well as in the combustion of dust in the air. This fills the indoor atmosphere with substances harmful to health. In addition, there may be harm to appearance heating appliances.

Another issue is safety in rooms with hot radiators. According to the general rules, it is supposed to protect heating devices, the surface temperature of which is above + 75ºС. Usually, lattice fences are used for this. They do not interfere with air circulation. At the same time, SNiP provides for mandatory protection of radiators in children's institutions.

In accordance with SNiP, Maximum temperature coolant varies depending on the purpose of the room. It is determined both by the characteristics of the heating of different buildings, and by security considerations. For example, in hospitals allowable temperature water in the pipes is the lowest. It is + 85ºС.

The maximum heated coolant (up to +150ºС) can be supplied to the following facilities:

• lobbies;
• heated pedestrian crossings;
• landings;
• technical premises;
• industrial buildings, in which there are no aerosols and dust prone to ignition.

The temperature schedule for supplying coolant to the heating system according to SNiP is used only in the cold season. In the warm season, the document in question normalizes the microclimate parameters only in terms of ventilation and air conditioning.

Each Management Company strive to achieve economical heating costs for an apartment building. In addition, residents of private houses are trying to come. This can be achieved if a temperature graph is drawn up, which will reflect the dependence of the heat produced by the carriers on weather conditions on the street. Correct use of these data allow optimal distribution of hot water and heating to consumers.

What is a temperature chart

The same mode of operation should not be maintained in the coolant, because outside the apartment the temperature changes. It is she who needs to be guided and, depending on her, change the temperature of the water in heating objects. The dependence of the coolant temperature on the outside air temperature is compiled by technologists. To compile it, the values ​​\u200b\u200bof the coolant and the outside air temperature are taken into account.

During the design of any building, the size of the heating equipment supplied in it, the dimensions of the building itself and the cross-sections of the pipes must be taken into account. In a high-rise building, residents cannot independently increase or decrease the temperature, as it is supplied from the boiler room. Adjustment of the operating mode is always carried out taking into account the temperature graph of the coolant. The temperature scheme itself is also taken into account - if the return pipe supplies water with a temperature above 70 ° C, then the coolant flow will be excessive, but if it is much lower, there is a shortage.

Important! The temperature schedule is drawn up in such a way that at any air temperature in the street, a stable temperature is maintained in the apartments. optimal level heating at 22 °C. Thanks to him, even the most severe frosts become not terrible, because the heating systems will be ready for them. If it is -15 ° C outside, then it is enough to track the value of the indicator to find out what the water temperature in the heating system will be at that moment. The more severe the outdoor weather, the hotter the water inside the system should be.

But the level of heating maintained indoors depends not only on the coolant:

• Temperature outside;
• The presence and strength of the wind - its strong gusts significantly affect heat loss;
• Thermal insulation - high-quality processed structural parts of the building help to keep heat in the building. This is done not only during the construction of the house, but also separately at the request of the owners.

Heat carrier temperature table from outdoor temperature

In order to calculate the optimal temperature regime, you need to take into account the characteristics that heating devices have - batteries and radiators. The most important thing is to calculate their specific power, it will be expressed in W / cm 2. This will most directly affect the transfer of heat from the heated water to the heated air in the room. It is important to take into account their surface power and the drag coefficient available for window openings and outer walls.

After all the values ​​\u200b\u200bare taken into account, you need to calculate the difference between the temperature in the two pipes - at the entrance to the house and at the exit from it. The higher the value in the inlet pipe, the higher in the return pipe. Accordingly, indoor heating will increase below these values.

Proper use of the coolant implies attempts by the inhabitants of the house to reduce the temperature difference between the inlet and outlet pipe. It could be construction work for wall insulation from the outside or thermal insulation of external heat supply pipes, insulation of ceilings above a cold garage or basement, insulation of the inside of the house or several works performed simultaneously.

Heating in the radiator must also comply with the standards. In the central heating systems usually varies from 70 C to 90 C depending on the air temperature outside. It is important to bear in mind that in the corner rooms it cannot be less than 20 C, although in other rooms of the apartment it is allowed to drop to 18 C. If the temperature drops to -30 C outside, then the heating in the rooms should rise by 2 C. In other rooms it should also increase the temperature, provided that it can be different in rooms for different purposes. If there is a child in the room, then it can range from 18 C to 23 C. In pantries and corridors, heating can vary from 12 C to 18 C.

It is important to note! taken into account average daily temperature- if the temperature is about -15 C at night, and -5 C during the day, then it will be calculated by the value of -10 C. If at night it was about -5 C, and in the daytime it rose to +5 C, then heating is taken into account by value 0 С.

Schedule for supplying hot water to the apartment

In order to deliver the optimal DHW to the consumer, CHP plants must send it as hot as possible. Heating mains are always so long that their length can be measured in kilometers, and the length of apartments is measured in thousands. square meters. Whatever the thermal insulation of the pipes, heat is lost on the way to the user. Therefore, it is necessary to heat the water as much as possible.


However, water cannot be heated to more than its boiling point. Therefore, a solution was found - to increase the pressure.

It is important to know! As it rises, the boiling point of water shifts upwards. As a result, it reaches the consumer really hot. With an increase in pressure, risers, mixers and taps do not suffer, and all apartments up to the 16th floor can be provided with hot water without additional pumps. In a heating main, water usually contains 7-8 atmospheres, the upper limit usually has 150 with a margin.

It looks like this:

The supply of hot water in the winter season must be continuous. Exceptions to this rule are accidents on heat supply. Hot water can be turned off only in the summer for preventive maintenance. Such work is carried out as in heating systems closed type as well as in open systems.