Looking through the statistics of visits to our blog, I noticed that search phrases such as, for example, very often appear “What should the coolant temperature be at minus 5 outside?”. I decided to post the old one schedule for qualitative regulation of heat supply based on average daily outside air temperature. I would like to warn those who, based on these figures, will try to figure out the relationship with housing departments or heating networks: heating schedules for each individual locality are different (I wrote about this in the article). They work according to this schedule heating network in Ufa (Bashkiria).
I also want to draw attention to the fact that regulation occurs according to average daily outside air temperature, so if, for example, outside at night minus 15 degrees, and during the day minus 5, then the coolant temperature will be maintained in accordance with the schedule at minus 10 o C.
Typically, the following temperature charts are used: 150/70 , 130/70 , 115/70 , 105/70 , 95/70 . The schedule is selected depending on specific local conditions. House heating systems operate according to schedules 105/70 and 95/70. Main heating networks operate according to schedules 150, 130 and 115/70.
Let's look at an example of how to use a chart. Let's say the temperature outside is minus 10 degrees. Heating networks operate according to a temperature schedule 130/70 , which means when -10 o C the temperature of the coolant in the supply pipeline of the heating network should be 85,6 degrees, in the supply pipe of the heating system - 70.8 o C with a 105/70 schedule or 65.3 o C with a 95/70 schedule. The water temperature after the heating system should be 51,7 about S.
As a rule, the temperature values in the supply pipeline of heating networks are rounded when assigned to a heat source. For example, according to the schedule it should be 85.6 o C, but at a thermal power plant or boiler house it is set to 87 degrees.
| Temperature outdoor air Tnv, o S |
Temperature of network water in the supply pipeline T1, o C |
Water temperature in the heating system supply pipe T3, o C |
Water temperature after the heating system T2, o C |
|||
|---|---|---|---|---|---|---|
| 150 | 130 | 115 | 105 | 95 | ||
| 8 | 53,2 | 50,2 | 46,4 | 43,4 | 41,2 | 35,8 |
| 7 | 55,7 | 52,3 | 48,2 | 45,0 | 42,7 | 36,8 |
| 6 | 58,1 | 54,4 | 50,0 | 46,6 | 44,1 | 37,7 |
| 5 | 60,5 | 56,5 | 51,8 | 48,2 | 45,5 | 38,7 |
| 4 | 62,9 | 58,5 | 53,5 | 49,8 | 46,9 | 39,6 |
| 3 | 65,3 | 60,5 | 55,3 | 51,4 | 48,3 | 40,6 |
| 2 | 67,7 | 62,6 | 57,0 | 52,9 | 49,7 | 41,5 |
| 1 | 70,0 | 64,5 | 58,8 | 54,5 | 51,0 | 42,4 |
| 0 | 72,4 | 66,5 | 60,5 | 56,0 | 52,4 | 43,3 |
| -1 | 74,7 | 68,5 | 62,2 | 57,5 | 53,7 | 44,2 |
| -2 | 77,0 | 70,4 | 63,8 | 59,0 | 55,0 | 45,0 |
| -3 | 79,3 | 72,4 | 65,5 | 60,5 | 56,3 | 45,9 |
| -4 | 81,6 | 74,3 | 67,2 | 62,0 | 57,6 | 46,7 |
| -5 | 83,9 | 76,2 | 68,8 | 63,5 | 58,9 | 47,6 |
| -6 | 86,2 | 78,1 | 70,4 | 65,0 | 60,2 | 48,4 |
| -7 | 88,5 | 80,0 | 72,1 | 66,4 | 61,5 | 49,2 |
| -8 | 90,8 | 81,9 | 73,7 | 67,9 | 62,8 | 50,1 |
| -9 | 93,0 | 83,8 | 75,3 | 69,3 | 64,0 | 50,9 |
| -10 | 95,3 | 85,6 | 76,9 | 70,8 | 65,3 | 51,7 |
| -11 | 97,6 | 87,5 | 78,5 | 72,2 | 66,6 | 52,5 |
| -12 | 99,8 | 89,3 | 80,1 | 73,6 | 67,8 | 53,3 |
| -13 | 102,0 | 91,2 | 81,7 | 75,0 | 69,0 | 54,0 |
| -14 | 104,3 | 93,0 | 83,3 | 76,4 | 70,3 | 54,8 |
| -15 | 106,5 | 94,8 | 84,8 | 77,9 | 71,5 | 55,6 |
| -16 | 108,7 | 96,6 | 86,4 | 79,3 | 72,7 | 56,3 |
| -17 | 110,9 | 98,4 | 87,9 | 80,7 | 73,9 | 57,1 |
| -18 | 113,1 | 100,2 | 89,5 | 82,0 | 75,1 | 57,9 |
| -19 | 115,3 | 102,0 | 91,0 | 83,4 | 76,3 | 58,6 |
| -20 | 117,5 | 103,8 | 92,6 | 84,8 | 77,5 | 59,4 |
| -21 | 119,7 | 105,6 | 94,1 | 86,2 | 78,7 | 60,1 |
| -22 | 121,9 | 107,4 | 95,6 | 87,6 | 79,9 | 60,8 |
| -23 | 124,1 | 109,2 | 97,1 | 88,9 | 81,1 | 61,6 |
| -24 | 126,3 | 110,9 | 98,6 | 90,3 | 82,3 | 62,3 |
| -25 | 128,5 | 112,7 | 100,2 | 91,6 | 83,5 | 63,0 |
| -26 | 130,6 | 114,4 | 101,7 | 93,0 | 84,6 | 63,7 |
| -27 | 132,8 | 116,2 | 103,2 | 94,3 | 85,8 | 64,4 |
| -28 | 135,0 | 117,9 | 104,7 | 95,7 | 87,0 | 65,1 |
| -29 | 137,1 | 119,7 | 106,1 | 97,0 | 88,1 | 65,8 |
| -30 | 139,3 | 121,4 | 107,6 | 98,4 | 89,3 | 66,5 |
| -31 | 141,4 | 123,1 | 109,1 | 99,7 | 90,4 | 67,2 |
| -32 | 143,6 | 124,9 | 110,6 | 101,0 | 94,6 | 67,9 |
| -33 | 145,7 | 126,6 | 112,1 | 102,4 | 92,7 | 68,6 |
| -34 | 147,9 | 128,3 | 113,5 | 103,7 | 93,9 | 69,3 |
| -35 | 150,0 | 130,0 | 115,0 | 105,0 | 95,0 | 70,0 |
Please do not rely on the diagram at the beginning of the post - it does not correspond to the data from the table.
Temperature graph calculation
The method for calculating the temperature graph is described in the reference book (Chapter 4, paragraph 4.4, p. 153).
This is a rather labor-intensive and time-consuming process, since for each outdoor temperature you need to count several values: T 1, T 3, T 2, etc.
To our joy, we have a computer and a spreadsheet processor MS Excel. A work colleague shared with me a ready-made table for calculating the temperature graph. It was made at one time by his wife, who worked as an engineer for a group of modes in thermal networks.
In order for Excel to calculate and build a graph, you just need to enter a few initial values:
- design temperature in the supply pipeline of the heating network T 1
- design temperature in return pipeline heating network T 2
- design temperature in the heating system supply pipe T 3
- Outdoor temperature T n.v.
- Indoor temperature T v.p.
- coefficient " n"(it is, as a rule, unchanged and equal to 0.25)
- Minimum and maximum cut of the temperature graph Cut min, Cut max.
All. nothing more is required from you. The calculation results will be in the first table of the sheet. It is highlighted with a bold frame.
The charts will also adjust to the new values.
The table also calculates the temperature of direct network water taking into account wind speed.
What laws govern changes in coolant temperature in systems? central heating? What is it - the temperature graph of the heating system is 95-70? How to bring heating parameters into line with the schedule? Let's try to answer these questions.
What it is
Let's start with a couple of abstract points.
- As weather conditions change, the heat loss of any building changes along with them. In frosty weather, in order to maintain a constant temperature in the apartment, much more thermal energy is required than in warm weather.
Let us clarify: heat costs are determined not by the absolute value of the air temperature outside, but by the delta between the street and the interior.
So, at +25C in the apartment and -20 in the yard, heat costs will be exactly the same as at +18 and -27, respectively.
- The heat flow from the heating device at a constant coolant temperature will also be constant.
A drop in temperature in the room will increase it slightly (again due to an increase in the delta between the coolant and the air in the room); however, this increase will be absolutely insufficient to compensate for the increased heat losses through the building envelope. Simply because the current SNiP limits the lower temperature threshold in an apartment to 18-22 degrees.
An obvious solution to the problem of increasing losses is to increase the temperature of the coolant.
Obviously, its increase should be proportional to the decrease outside temperature: the colder it is outside, the greater the heat loss will have to be compensated. Which, in fact, brings us to the idea of creating a specific table for reconciling both values.
So, the schedule temperature system heating is a description of the dependence of the temperatures of the supply and return pipelines on the current weather outside.
How everything works
There are two different types graphs:
- For heating networks.
- For in-house heating system.
To clarify the difference between these concepts, it might be worth starting with short excursion into how central heating works.
CHP – heating networks
The function of this bundle is to heat the coolant and deliver it to the end user. The length of heating mains is usually measured in kilometers, the total surface area - in thousands and thousands square meters. Despite measures to insulate pipes, heat loss is inevitable: having passed the path from the thermal power plant or boiler room to the border of the house, process water will have time to partially cool down.
Hence the conclusion: in order for it to reach the consumer while maintaining an acceptable temperature, the supply of the heating main at the exit from the thermal power plant must be as hot as possible. The limiting factor is the boiling point; however, as the pressure increases, it shifts towards increasing temperature:
| Pressure, atmosphere | Boiling point, degrees Celsius |
| 1 | 100 |
| 1,5 | 110 |
| 2 | 119 |
| 2,5 | 127 |
| 3 | 132 |
| 4 | 142 |
| 5 | 151 |
| 6 | 158 |
| 7 | 164 |
| 8 | 169 |
Typical pressure in the supply pipeline of a heating main is 7-8 atmospheres. This value, even taking into account pressure losses during transportation, allows you to start a heating system in buildings up to 16 floors high without additional pumps. At the same time, it is safe for routes, risers and connections, mixer hoses and other elements of heating and hot water systems.
With some margin, the upper limit of the supply temperature is taken to be 150 degrees. The most typical heating temperature curves for heating mains are in the range of 150/70 – 105/70 (supply and return temperatures).
House
There are a number of additional limiting factors in a home heating system.
- The maximum temperature of the coolant in it cannot exceed 95 C for a two-pipe and 105 C for.
By the way: in preschool educational institutions the limit is much more stringent - 37 C.
The price of lowering the supply temperature is an increase in the number of radiator sections: in the northern regions of the country, group rooms in kindergartens are literally surrounded by them.
- For obvious reasons, the temperature delta between the supply and return pipelines should be as small as possible - otherwise the temperature of the batteries in the building will vary greatly. This implies rapid circulation of the coolant.
However, too rapid circulation through house system heating will lead to the fact that the return water will return to the route with an exorbitant high temperature, which is unacceptable due to a number of technical limitations in the operation of thermal power plants.
The problem is solved by installing one or more elevator units in each house, in which return water is mixed with the flow of water from the supply pipeline. The resulting mixture, in fact, ensures rapid circulation of a large volume of coolant without overheating the return pipeline of the route.
For intra-house networks, a separate temperature schedule is set taking into account the elevator operation scheme. For two-pipe circuits, the typical heating temperature curve is 95-70, for single-pipe circuits (which, however, is rare in apartment buildings) - 105-70.
Climate zones
The main factor determining the scheduling algorithm is the estimated winter temperature. The coolant temperature table must be drawn up in such a way that the maximum values (95/70 and 105/70) at the peak of frost provide the temperature in residential premises corresponding to SNiP.
Let's give an example of an intra-house graph for the following conditions:
- Heating devices - radiators with coolant supply from bottom to top.
- Heating is two-pipe, with .
- The estimated outside air temperature is -15 C.
| Outside air temperature, C | Feed, C | Return, C |
| +10 | 30 | 25 |
| +5 | 44 | 37 |
| 0 | 57 | 46 |
| -5 | 70 | 54 |
| -10 | 83 | 62 |
| -15 | 95 | 70 |
A nuance: when determining the parameters of the route and the intra-house heating system, the average daily temperature is taken.
If it is -15 at night and -5 during the day, the outside temperature is -10C.
And here are some calculated values winter temperatures for Russian cities.
| City | Design temperature, C |
| Arkhangelsk | -18 |
| Belgorod | -13 |
| Volgograd | -17 |
| Verkhoyansk | -53 |
| Irkutsk | -26 |
| Krasnodar | -7 |
| Moscow | -15 |
| Novosibirsk | -24 |
| Rostov-on-Don | -11 |
| Sochi | +1 |
| Tyumen | -22 |
| Khabarovsk | -27 |
| Yakutsk | -48 |
The photo shows winter in Verkhoyansk.
Adjustment
If the management of the thermal power plant and heating networks is responsible for the parameters of the route, then responsibility for the parameters of the intra-house network rests with the housing residents. A very typical situation is when, when residents complain about the cold in their apartments, measurements show deviations from the schedule downwards. It happens a little less often that measurements in thermal wells show an elevated return temperature from the house.
How to bring the heating parameters into line with the schedule with your own hands?
Reaming the nozzle
When the temperature of the mixture and return is low, the obvious solution is to increase the diameter of the elevator nozzle. How it's done?
Instructions are at the reader's disposal.
- All valves or valves are closed elevator unit(entrance, house and hot water supply).
- The elevator is being dismantled.
- The nozzle is removed and drilled 0.5-1 mm.
- The elevator is assembled and started with air bleeding in the reverse order.
Advice: instead of paronite gaskets, you can put rubber gaskets on the flanges, cut to the size of the flange from a car inner tube.
An alternative is to install an elevator with an adjustable nozzle.
Choke suppression
In critical situations (extreme cold and freezing apartments), the nozzle can be completely removed. To prevent the suction from becoming a jumper, it is suppressed with a pancake made of steel sheet at least a millimeter thick.
Attention: this is an emergency measure used in extreme cases, since in this case the temperature of the radiators in the house can reach 120-130 degrees.
Differential adjustment
At elevated temperatures as a temporary measure until the end heating season It is practiced to adjust the differential on the elevator using a valve.
- The DHW switches to the supply pipe.
- A pressure gauge is installed on the return line.
- The inlet valve on the return pipeline is completely closed and then gradually opens with pressure controlled by a pressure gauge. If you simply close the valve, the subsidence of the cheeks on the rod can stop and defrost the circuit. The difference is reduced by increasing the return pressure by 0.2 atmospheres per day with daily temperature control.
Conclusion
When autumn confidently strides across the country, snow is flying above the Arctic Circle, and in the Urals night temperatures stay below 8 degrees, then the word form “heating season” sounds appropriate. People remember past winters and try to understand the normal temperature of the coolant in the heating system.
Prudent owners of individual buildings carefully inspect the valves and nozzles of boilers. Residents apartment building by October 1, they are waiting, like Santa Claus, for a plumber from management company. The Lord 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. The outback prays to five-story buildings. Until demolished, the house operates a calorie supply system.
Heating of an economy class apartment building is carried out through a centralized heat supply system. Pipes are included in basement buildings. The supply of coolant is regulated by inlet valves, after which the water enters the mud traps, and from there it is distributed through the risers, and from them it is supplied to the radiators and radiators that heat the home.
The number of valves correlates with the number of risers. By doing repair work in a separate apartment, it is possible to turn off one vertical, and not the entire house.
The waste liquid is partially discharged through the return pipe, and partially supplied to the hot water supply network.
Degrees here and there
Water for the heating configuration is prepared at a thermal power plant or in a boiler room. The norms for water temperature in the heating system are specified in building regulations ah: the component must be heated to 130-150 °C.
The supply is calculated taking into account the parameters of the outside air. Yes, for the region Southern Urals 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 will tear them apart like a hot water bottle.
An elastic concept is a norm. The temperature in the apartment is never equal to the primary indicator of the coolant. Here, the elevator unit - a jumper between the forward and return pipes - performs an energy-saving function. The temperature standards for the coolant in the return heating system in winter allow heat to be maintained at a level of 60 °C.
Liquid from the direct pipe enters the elevator nozzle, mixes with return water and again goes into home network for heating. The temperature of the carrier is reduced by mixing the return fluid. What affects the calculation of the amount of heat consumed by residential and utility rooms.
The hot one went
Temperature hot water By sanitary rules at analysis points should be in the range of 60-75 °C.
In the network, the coolant is supplied from the pipe:
- in winter - with reverse, so as not to scald users with boiling water;
- in summer - from a straight line, since in summer time The carrier is heated no higher than 75 °C.
A temperature chart is drawn up. The average daily return water temperature 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 the riser through which the coolant enters the battery or radiator from the Coolant temperature standards in the heating system require heating in the riser in winter in the range of 70-90 °C. In fact, the degrees depend on the output parameters of the thermal power plant or boiler house. In the summer, when hot water is needed only for washing and showering, the range moves to 40-60 °C.
Observant people may notice that the heating elements in the neighboring apartment are hotter or colder than in his own.
The reason for the temperature difference in the heating riser lies in the method of hot water distribution.
In a single-pipe design, the coolant can be distributed:
- above; then the temperature on the upper floors is higher than on the lower ones;
- 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 reverse direction.
Warm like a battery
Let’s assume that the central network structures are reliably insulated along the entire route, the wind does not blow through attics, staircases and basements, and conscientious owners have insulated the doors and windows in the apartments.
Let's assume that the coolant in the riser complies with building code standards. It remains to find out what the normal temperature of the heating radiators in the apartment is. The indicator takes into account:
- outdoor air parameters and time of day;
- location of the apartment in the house plan;
- residential or utility room in the apartment.
Therefore, attention: it is important not what the temperature of the heater is, but what the temperature of the air in the room is.
During the day in corner rooms the thermometer must show at least 20 °C, and in centrally located rooms 18 °C is allowed.
At night, air in the home is allowed to be 17 °C and 15 °C, respectively.
Theory of linguistics
The name “battery” is a common one, meaning a number of identical objects. In relation to home heating, this is a series of heating sections.
Temperature standards for heating radiators 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 covered with plywood or bricked. Usually a lattice fence is installed that does not impede air circulation.
Cast iron, aluminum and bimetallic devices are common.
Consumer choice: cast iron or aluminum
Aesthetics cast iron radiators- the talk of the town. They require periodic painting, since the rules require that the working surface have a smooth surface 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 technical specifications cast iron products at height:
- are slightly susceptible to water corrosion and can be used for more than 45 years;
- have high thermal power per section, therefore they are compact;
- are inert in heat transfer, so they smooth out temperature changes in the room well.
Another type of radiator is made of aluminum. Lightweight design, factory painted, does not require painting, easy to maintain.
But there is a drawback that overshadows the advantages - corrosion in aquatic environment. Certainly, inner surface The heater is insulated with plastic to avoid contact of aluminum with water. But the film may be damaged, then it will start chemical reaction with the release of hydrogen during creation overpressure gas, the aluminum device may burst.
The temperature standards for heating radiators are subject to the same rules as batteries: it is not so much the heating of a metal object that is important, but the heating of the air in the room.
In order for the air to warm up well, there must be sufficient heat removal from work surface heating structure. Therefore, it is strictly not recommended to increase the aesthetics of the room with shields in front of the heating device.
Stairwell heating
Since we're talking about apartment building, then it should be mentioned staircases. The coolant temperature standards in the heating system state: the degree measure at the sites should not fall below 12 °C.
Of course, the residents' discipline requires closing the doors tightly entrance group, do not leave the transoms of the staircase 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 points of probable heat loss and maintain temperature conditions in the house, an application for recalculation of the cost of services will help.
Changes in heating design
Replacement of existing heating devices in an apartment is carried out with the obligatory approval of the management company. Unauthorized changes in the elements of warming radiation can disrupt the thermal and hydraulic balance of the structure.
When the heating season begins, changes in temperature conditions in other apartments and areas will be recorded. A technical inspection of the premises will reveal unauthorized changes in the types of heating devices, their quantity and size. The chain is inevitable: conflict - court - fine.
Therefore, the situation is resolved like this:
- if non-old ones are replaced with new radiators of the same size, then this is done without additional approvals; the only thing you need to contact the management company for is to turn off the riser during repairs;
- if new products differ significantly from those installed during construction, then it is useful to interact with the management company.
Heat meters
Let us remember once again that the heat supply network of an apartment building is equipped with thermal energy metering units, which record both the gigacalories consumed and the cubic capacity of water passed through the intra-house line.
In order not to be surprised by bills containing unrealistic amounts for heat when the degrees in the apartment are below normal, before the start of the heating season, check with the management company whether the meter is in working condition and whether the verification schedule has been violated.
Most city apartments are connected to the central heating network. The main source of heat in large cities is usually boiler houses and thermal power plants. A coolant is used to provide heat in the house. As a rule, this is water. It is heated to a certain temperature and fed into the heating system. But the temperature in the heating system can be different and is related to the temperature of the outside air.
To effectively provide heat to city apartments, regulation is necessary. Observe set mode heating is helped by the temperature graph. What is a heating temperature schedule, what types are there, where is it used and how to draw it up - the article will tell you about all this.
The temperature graph is understood as a graph that shows the required water temperature in the heating system depending on the level of outside air temperature. Most often, the heating temperature schedule is determined for central heating. According to this schedule, heat is supplied to city apartments and other objects that are used by people. This schedule allows you to maintain optimal temperature and save heating resources.
When is a temperature chart needed?
In addition to central heating, the schedule is widely used in domestic autonomous heating systems. In addition to the need to regulate the temperature in the room, the schedule is also used to provide safety measures when operating household heating systems. This is especially true for those who install the system. Since the choice of equipment parameters for heating an apartment directly depends on the temperature schedule.
Based on the climatic conditions and temperature schedule of the region, a boiler and heating pipes are selected. The power of the radiator, the length of the system and the number of sections also depend on the temperature established by the standard. After all, the temperature of the heating radiators in the apartment must be within the standard limits. You can read about the technical characteristics of cast iron radiators.
What are the temperature charts?
Schedules may vary. The standard temperature of the apartment heating radiators depends on the chosen option.
The choice of a specific schedule depends on:
- climate of the region;
- boiler room equipment;
- technical and economic indicators of the heating system.
There are single- and two-pipe system heat supply.
The heating temperature graph is indicated by two numbers. For example, the heating temperature graph 95-70 is deciphered as follows. For supporting desired temperature air in the apartment, the coolant should enter the system at a temperature of +95 degrees, and exit at a temperature of +70 degrees. Typically, this type of graph is used for autonomous heating. All old houses up to 10 floors high are designed for a heating schedule of 95-70. But if the house has a large number of floors, then a heating temperature schedule of 130-70 is more suitable.
In modern new buildings, when calculating heating systems, the 90-70 or 80-60 schedule is most often adopted. True, another option may be approved at the discretion of the designer. The lower the air temperature, the higher the temperature of the coolant entering the heating system. The temperature schedule is selected, as a rule, when designing the heating system of a structure.
Features of scheduling
Temperature chart indicators are developed based on the capabilities of the heating system, heating boiler, and temperature changes outside. By creating a temperature balance, you can use the system more carefully, which means it will last much longer. Indeed, depending on the materials of the pipes and the fuel used, not all devices are and are not always able to withstand sudden temperature changes.
When choosing the optimal temperature, you are usually guided by the following factors:
It should be noted that the temperature of the water in the central heating radiators should be such that it will allow the building to warm up well. For different rooms Various normative values have been developed. For example, for a residential apartment the air temperature should not be less than +18 degrees. In kindergartens and hospitals this figure is higher: +21 degrees.
When the temperature of the heating radiators in the apartment is low and does not allow heating the room to +18 degrees, the apartment owner has the right to contact the utility service to increase the heating efficiency.
Since the room temperature depends on the season and climatic conditions, the temperature standard for heating radiators may be different. The heating of water in the heating system of a building can vary from +30 to +90 degrees. When the water temperature in the heating system is above +90 degrees, then decomposition begins paint coating, dust. Therefore, heating the coolant above this mark is prohibited by sanitary standards.
It must be said that the calculated outside air temperature for heating design depends on the diameter of the distribution pipelines, the size of the heating devices and the coolant flow in the heating system. There is a special table of heating temperatures that makes it easier to calculate the schedule.
The optimal temperature in heating radiators, the norms of which are set according to the heating temperature schedule, allows you to create comfortable conditions accommodation. More details about bimetallic radiators heating can be found out .
Temperature chart installed for each heating system.
Thanks to it, the temperature in the home is maintained at optimal level. Schedules may vary. Many factors are taken into account to develop them. Any schedule must be approved by an authorized city agency before being put into practice.
The supply of heat to a room is associated with a simple temperature schedule. The temperature values of the water supplied from the boiler room do not change in the room. They have standard values and range from +70ºС to +95ºС. This temperature schedule for the heating system is the most popular.
Adjusting the air temperature in the house
Not everywhere in the country there is central heating, so many residents install independent systems. Their temperature graph differs from the first option. In this case temperature indicators significantly reduced. They depend on the efficiency of modern heating boilers.
If the temperature reaches +35ºС, the boiler will operate at maximum power. It depends on the heating element, Where thermal energy can be picked up by exhaust gases. If the temperature values are greater than + 70 ºС, then the boiler performance drops. In that case, in his technical specifications efficiency is indicated at 100%.
Temperature schedule and its calculation
What the graph will look like depends on the outside temperature. The more negative meaning outside temperature, the greater the heat loss. Many people do not know where to get this indicator. This temperature is prescribed in regulatory documents. The temperature of the coldest five-day period is taken as the calculated value, and the lowest value over the last 50 years is taken.
Graph of the dependence of external and internal temperatures
The graph shows the relationship between external and internal temperatures. Let's say the outside temperature is -17ºС. Drawing a line upward until it intersects with t2, we obtain a point characterizing the temperature of the water in the heating system.
Thanks to the temperature schedule, you can prepare the heating system even for the most severe conditions. It also reduces material costs for installing a heating system. If we consider this factor from the point of view of mass construction, the savings are significant.
inside premises depends from temperature coolant, A Also others factors:
- Outside air temperature. The smaller it is, the more negatively it affects heating;
- Wind. Whenever strong wind heat loss increases;
- Indoor temperature depends on thermal insulation structural elements building.
Over the past 5 years, construction principles have changed. Builders increase the value of a home by insulating elements. As a rule, this applies to basements, roofs, and foundations. These expensive measures subsequently allow residents to save on the heating system.
Heating temperature chart
The graph shows the dependence of the outside temperature and internal air. The lower the outside air temperature, the higher the coolant temperature in the system will be.
A temperature chart is developed for each city during heating season. In small populated areas a temperature schedule is drawn up for the boiler room, which ensures required amount coolant to the consumer.
Change temperature schedule Can several ways:
- quantitative - characterized by a change in the flow rate of coolant supplied to the heating system;
- qualitative - consists of regulating the temperature of the coolant before supplying it to the premises;
- temporary - a discrete method of supplying water to the system.
The temperature schedule is a schedule of heating pipes that distributes the heating load and is regulated using centralized systems. There is also an increased schedule; it is created for a closed heating system, that is, to ensure the supply of hot coolant to connected objects. When using open system it is necessary to adjust the temperature schedule, since the coolant is consumed not only for heating, but also for domestic water consumption.
The temperature graph is calculated using simple method. Hto build it, necessary initial temperature air data:
- external;
- in room;
- in the supply and return pipelines;
- at the exit of the building.
In addition, you should know the rated thermal load. All other coefficients are standardized by reference documentation. The system is calculated for any temperature schedule, depending on the purpose of the room. For example, for large industrial and civil facilities a schedule of 150/70, 130/70, 115/70 is drawn up. For residential buildings this figure is 105/70 and 95/70. The first indicator shows the supply temperature, and the second - the return temperature. The calculation results are entered into a special table, which shows the temperature at certain points of the heating system, depending on the outside air temperature.
The main factor when calculating the temperature graph is outside temperature air. The calculation table must be drawn up so that the maximum values of the coolant temperature in the heating system (graph 95/70) ensure heating of the room. Room temperatures are provided regulatory documents.
heating devices
The main indicator is the temperature of heating devices. The ideal temperature schedule for heating is 90/70ºС. It is impossible to achieve such an indicator, since the temperature inside the room should not be the same. It is determined depending on the purpose of the room.
In accordance with the standards, the temperature in the corner living room is +20ºС, in the rest – +18ºС; in the bathroom – +25ºС. If the outside air temperature is -30ºС, then the indicators increase by 2ºС.
Except Togo, exists norms For others types premises:
- in rooms where children are located – +18ºС to +23ºС;
- children's educational institutions – +21ºС;
- in cultural institutions with mass attendance – +16ºС to +21ºС.
This range of temperature values is compiled for all types of premises. It depends on the movements performed inside the room: the more of them, the fewer topics air temperature. For example, in sports facilities people move a lot, so the temperature is only +18ºС.
Room temperature
Exist certain factors, from which depends temperature heating devices:
- Outside air temperature;
- Type of heating system and temperature difference: for single pipe system– +105ºС, and for single-pipe – +95ºС. Accordingly, the differences in for the first region are 105/70ºС, and for the second – 95/70ºС;
- Direction of coolant supply to heating devices. With the top feed, the difference should be 2 ºС, with the bottom – 3 ºС;
- Type of heating devices: heat transfer is different, so the temperature curve will be different.
First of all, the coolant temperature depends on the outside air. For example, the temperature outside is 0ºC. Wherein temperature regime in radiators it should be equal to 40-45ºС at the supply, and 38ºС at the return. When the air temperature is below zero, for example -20ºС, these indicators change. In this case, the supply temperature becomes 77/55ºС. If the temperature reaches -40ºС, then the indicators become standard, that is, +95/105ºС at the supply, and +70ºС at the return.
Additional options
In order for a certain temperature of the coolant to reach the consumer, it is necessary to monitor the condition of the outside air. For example, if it is -40ºС, the boiler room should supply hot water with an indicator of +130ºС. Along the way, the coolant loses heat, but the temperature still remains high when it enters the apartments. Optimal value+95ºС. To do this, an elevator unit is installed in the basements, which serves to mix hot water from the boiler room and coolant from the return pipeline.
Several institutions are responsible for the heating main. The boiler room monitors the supply of hot coolant to the heating system, and the condition of the pipelines is monitored by city heating networks. The housing office is responsible for the elevator element. Therefore, in order to solve the problem of coolant supply to new house, you need to contact different offices.
Installation of heating devices is carried out in accordance with regulatory documents. If the owner himself replaces the battery, then he is responsible for the operation of the heating system and changes in temperature conditions.
Adjustment methods
Dismantling the elevator unit
If the boiler room is responsible for the parameters of the coolant leaving the warm point, then the housing office workers must be responsible for the temperature inside the room. Many residents complain about the cold in their apartments. This occurs due to a deviation in the temperature graph. In rare cases, it happens that the temperature rises by a certain value.
Heating parameters can be adjusted in three ways:
- Reaming the nozzle.
If the supply and return coolant temperatures are significantly underestimated, then it is necessary to increase the diameter of the elevator nozzle. This way, more liquid will pass through it.
How to do this? To begin with, it overlaps shut-off valves(house valves and taps at the elevator unit). Next, the elevator and nozzle are removed. Then it is drilled out by 0.5-2 mm, depending on how much it is necessary to increase the temperature of the coolant. After these procedures, the elevator is mounted in its original place and put into operation.
To ensure sufficient tightness of the flange connection, it is necessary to replace the paronite gaskets with rubber ones.
- Silence the suction.
In severe cold weather, when the problem of freezing of the heating system in the apartment arises, the nozzle can be completely removed. In this case, the suction may become a jumper. To do this, you need to plug it with a steel pancake 1 mm thick. This process is carried out only in critical situations, since the temperature in the pipelines and heating devices will reach 130ºС.
- Adjustment of difference.
In the middle of the heating season, a significant increase in temperature may occur. Therefore, it is necessary to regulate it using a special valve on the elevator. To do this, the supply of hot coolant is switched to the supply pipeline. A pressure gauge is mounted on the return line. Adjustment occurs by closing the valve on the supply pipeline. Next, the valve opens slightly, and the pressure should be monitored using a pressure gauge. If you simply open it, the cheeks will sag. That is, an increase in pressure drop occurs in the return pipeline. Every day the indicator increases by 0.2 atmospheres, and the temperature in the heating system must be constantly monitored.
