What is a temperature delta in heating. Temperature schedule of the heating system: Get acquainted with the mode of operation of the CSO. About saving on recycling

I decided to do myself.
So how much to take the heat transfer section, and where to see how much real?

Answer:

The heat transfer in advertising (passport) is usually given at Delta T \u003d 70 for sectional radiators. What is not really practical. Since the feed is obtained by 95, the radiator feed / reverse on the radiator \u003d 95/85, the air surrounding 20 degrees.

Look on the site of the manufacturer which heat transfer at Delta T \u003d 50. That is the flow of the boiler 75, radiators 75/65, the ambient air - 20 degrees. Also not always such real. On radiators there may be a larger difference than 75/65. For example, 75/55

For example, consider the mode and for the boiler, and for the radiators of such (with two-pipe CO). The supply of boiler 60, radiators 60/40 (average 50), air - 23. We have "Delta T" \u003d 27 degrees.

Very rude can derive the heat transfer coefficient (rough, because the dependence of heat transfer from the "Delta T" is not linear). "Delta T", in 70g / 27g \u003d 2.59. So reducing the advertising power of the radiators, leading to a real output power, applying this coefficient.

If the manufacturer of radiators is given a formula for recalculating the thermal power of radiators (such as Kermi-like), then the real power can be calculated by the very meaning of the real "delta T". Please note that the capacity table of the manufacturer radiators is given with the specified "delta T" degrees.

Message-question

Thanks for your answers, now I have a little imagine how it works, and sorry for stupid questions on my part.

Now about your questions. Radiators plan to put - Bimetallic radiator Rifar Forza 500 (nominal heat flux 202 W, 0.2 liter volume), there are for sale at the place of residence. Number 56 - 60 pcs.

erikra said (a):

If the boiler is a clock overheating, then the elongation of the "route" of circulation is not enough, since losses on the length of the pipeline will be small, when using polymer pipes, even less, and if they are also isolated ... In general, IMHO, it is not occasion...

Answer:

If you wrote that you have IMHO (you have an opinion of the horseradish you will challenge), then everyone will remain with her opinion.

To whom I want to learn more about the principle of "routes", bypass, circulation, "thermal failures" and otherwise contact PM.

erikra said (a):

I did not quite understand ... if "the head of the pump's pump ended", then the boiler still "will not recognize" that it is time to turn on any of the "whom", except from the room thermostat. And the installation of the bypass in the end of the branch "Knowledge" will not add. And it is easier to solve this, IMHO, easier by installing a room thermostat to the room that cools faster.

Answer:

Yes of course. In such a room, and the thermostat is not equipped with thermal heads and put the heating devices.

BUT! The boiler does not turn on by a room thermostat signal. Do not enter, please mislead. Room thermostat only prohibits the boiler to work, or removes the ban. And it is turned on or not to turn on, the boiler makes a solution based on the readings of the built-in temperature sensors at the boiler output (feed), well, and a small amount can still track not only the feed, but also the return. But this is the topic of a separate conversation for the section "Gas boilers".

Those. The automation of the boiler "will not be able to learn" that in the distant ends of the highways has already sucked and it's time to turn on. And if the highway someone climbed into the walls or tie of the floor, next to the "cold bridges", but not long and hardening the highway.

Doctoreshov asked:

Tell me, in this scheme - what is the "companion" better "ones"? The problem is "travelers" - the end of the branch for children - should pass through the second light - the inconvenience of the installation.

Answer:

More precisely, no "ones", but a "dead-end" two-pipe system. The fact that all radiator contours (meaning individual radiators) have approximately the same hydrodynamic resistance in the system (naturally, if the radiators are the same). Ie, the "passing" two-tube is more balanced hydraulically in itself initially. And most often works fine (evenly on radiators), even without carrying out the system balancing. According to its own principle of work. But balancing should not be neglected, because the cost of gas may depend on the quality of the balancing.

A "dead-up" two-pipe system is initially unbalanced. And without balancing does not work correctly.

And on the "fellow" (for one contour) so you can hang much more radiators. But in the "dead-end" two-pipe system, more than five radiators in one branch are undesirable. Otherwise, it will be more reasonable to increase the diameters of the highways, or there will be bad balance, which may not be able to eliminate even balancing.

P.S. Many, "dead-end" two-pipe systems, with several dead branches, where in one branch seven, for another twelve, and on the third fifteen radiators. And then there are talk on the forums that, they say, a two-tube balancing hard. And of course, no balancing reinforcement for radiators was not set. Of course, in such an incorrectly designed and mounted version, and it is not foreseen of a normal uniform warming of radiators. Some of them will not be warm or partially. Attempting to balance the system using conventional ball valves (not special types of KRPSH) on the returns of radiators - most often failed, not to mention that the ball valves in half-open states quickly fail. For understanding, try to adjust the conventional ball valve, the flow of water from the hose for watering colors in the pots desired thin flowing. This will be the most visible example, how incuffed to balance the systems with the help of ball cranes.

Question:

Why then does the scheme not work?:

After all, all radiators are almost the same, and the diameters of the pipes are also equal everywhere, which means the hydraulic resistance of all sites should be the same? Or what is the reason?

Answer:

The hydraulic resistance of all sections is not equal to true. Depends on the number of radiators, and on the connection method, and on the number of sections.

The first, why it does not work - this is the absence of shut-off-balancing valves on the reversals of radiators. Instead of angular shut-off valves, ordinary corners with American women were applied.

The second, why it does not work - this is the use of metal-plastic pipes on highways. More precisely, the presence of strong "seasons" in the tees-fittings for MP in the inner passage. Thus, both highways and feed and returns were "rejected". It would seem that the pipe MP20mm, equivalent to the bandwidth of the steel pipe ¾ inch. But in reality, due to a narrow internal passage in MP-tees, the throughput of the highways was significantly lower, even with a steel pipe ½ inches.

In MP-tee 20-16-20 mm through passage somewhere about 12 mm, which corresponds to the more steel pipe 3/8 inches, or even less. Those. The throughput of highways, it turned out, about four times less required. The boiler pump was "suffocked", and most likely a rather large share circulates not on the highways, but on the inner "small" circle of the boiler, through the bypass valve on the bypass. If the boiler is very often clocking, then most likely, in this case, the part is circulating only inside the "small circle" boiler.

Perhaps there are other reasons why the system does not work, made according to the scheme above, it is not visible from here, unfortunately. Same scheme is faithful and good. But why the system itself does not work, there may be a bunch of other causes of inoperability, except for the scheme. If you want to see the photo, but measure the temperature across the entire system at checkpoints, you could still have something to assume.

And so while the fortune telling on the coffee grounds, sorry. It is not known which fittings was applied, etc. etc. Also, the installers could not take into account that water has inertia (Imuls E \u003d M * V), which in reality the boiler is performed (a filter-mesh is possible, it is too small in diameter), and so paragraph. Etc.

Here is a real example of illiterate and competent installation. In the first scheme will always work correctly. In the second scheme is not always. Those. In the diagram, the five-piece radiator is unlikely to work, because he may have a circulation of "back". And the scheme is the principled of these two connections the same! In the first scheme - illiterately. On the second - competently. Those, the hydraulics of streams in tees, as well as the inertia of water is not taken into account.

erikra said:

Why guess then. You just need to look into the "letter", the same scanvavi, for example. There is such a picture

These are the main circulation rings, i.e. What makes the calculation begins. Everything else, these are secondary circulating rings, i.e., the very "matryoshki" that you said about.

And the rings of the supply line and the returns do not happen ... What are these rings? Only halves. The ring includes and feeding, and the return, and the heating device ... Ring, it is the ring.

That's each ring and linked ...

Answer:

Thanks for the scheme, clearly explaining the hydrosistration of radiators in the "dead-end" and in the "passing" schemes of two-pipe heating systems. Also, this scheme clearly demonstrates the advantages of the diagonal connection of radiators, in front of the side connections.

I will try "on the fingers" again to explain the advantage of "travelers" before the "dead-end", just on this convenient scheme.

Water goes along the path of least resistance.

Therefore, in the scheme A)

water "would prefer" to follow the circuit A-1-1 "-B, rather than by contour A-7-7" -B, because the contour A-1-1 "-B has a significantly less resistance, but it is more correct to say hydrodynamic resistance. It should also be forgotten that water has a mass, and moves at a certain speed in the pipe, therefore it has a rather small pulse E \u003d MV.

And all this will result in the fact that if you do not install additional resistors (balancing valves) in these circuits and not balance such a dead-end two-tube, then the closer to the end in a dead-end branch, the smaller there will be water circulation. And starting with some radiators, it may even start from the middle of the dead-end branch, in general may not be circulation.

In the scheme b)

water "without a difference where to go", because the hydrodynamic resistance that the circuit is A-1-1 "-B, that the contour A-4-4" -B, that A-7-7 "-B is the same. Therefore, such a scheme with the traveler It can be considered balanced if plots 1-1 "(and so on to 7-7") have equal hydrodynamic resistance, as on the concept of the schema. In reality, radiators can have a different number of sections (or sizes) can also have different Connection (side or diagonal). Therefore, even when applying a two-tube scheme with a traveler, you need to install balancing valves on the radiators rates (especially since such a valve also replaces the ball valve and the American, so there is less money for money).

And these rings discussed above are not linked, but are balanced to an equal fluid of hydrodynamic resistance. This is called the system balancing.

erikra said (a):

About Bernoulli, is it, like, what about it?

Answer:

If anyone has such love, to one-pipe system, it is better to do so.

On the average tank of the tee of PP 25mm, the pressure of water (in dynamics, but not in the statics) will be less than on the average tower of the tee of PP 32-25-32. Therefore, at the inlet to the radiator will be greater pressure than at the output, which will increase the circulation through the radiator. Although the shown tees of PP 25mm still "shack" the highway and the total circulation according to it. With a diagonal connection, even without the sediment shown in the tee, due to gravity, circulation through the radiator will still be carried out. But naturally, it depends on the internal hydrodynamic resistance of the radiator. For cast iron and aluminum, the connection is also suitable for the connection of the bottom even without shown schematic reception with the align (but with a decrease in heat transfer). But for steel panel radiators, it may already be necessary to apply such a solution. Or apply the special fittings of the bottom connection type "binoculars" for single-tube systems with adjustable bypass.

But such fittings are not at all budgeted. What to make a single-pipe system? According to materials, it will be more expensive than a two-tube, and have significantly more operational deficiencies compared to a two-pipe system.

For some reason, talking about sediments, most of the masters forget (or does not know) about the investigation of Bernoulli, although the master and speaks often about the "local resistances":

"How much fluid passes through one section of the pipe over a while, the same amount should pass over the same time through any other section (through the connected connected section of the pipeline)." Consequence of Bernoulli law.

And in a one-tube it is a consistently connected portion of the pipeline. Therefore, if we zazuim the passage at least in one place of the contour of one-tube, we thus reducing the duct through the entire contour.

erikra said:

For sure, this is a big "cant" of this engineer ... Neither to delete, nor the radiator to remove ... What did he think?

Although not everything is so scary as it seems. Judging by the photo, there is a chance to establish, instead of these angular amenities, an angular reverse radiator crane. By size, IMHO, the same ... Well, or close ...

Not a fact ... When all the thermal heads open, it can get the same effect that has now. Better, nevertheless, put inverse radiator cranes.

Answer:

Yes, of course better. But if, a person has no desire or opportunity, without waiting for the end of the heating season to remount the system, and stay for several days without heating, it is easier to install thermal heads. You do not have to stop heating, merge water and so on.

Yes, it is possible that the balance will not come. But only if the power of radiators, Eytim Angener was chosen too small, that is, insufficient. Only in this case the thermal heads will not be covered. But even in this case, you can make balancing at the expense of the thermal heads. By setting the thermal heads to a smaller temperature, for example, in non-residential or low-transmitted rooms. That is, to put the thermal heads not to support 25 degrees, and up to 20, or even up to 18 (and below before the onset of self-balance).

If the power of the radiators is chosen correctly, the thermal heads will definitely begin to "press" the flow through the radiators, thereby automatically balancing the hydroxistance of the contours of various radiators among themselves. And the system is automatically self-balancing.

Flowing two-pipe system with associated water movement. Or another is called "with a loop of Tichelman." The "telescope" method (method of variable diameter of the highway).

This hydraulic scheme has all the advantages of two-pipe systems and at the same time deprived of a lack of pressure drops inherent in the implicit schemes.

Hot water from the boiler (feed) passes through the supply pipeline of the decreasing diameter, (the "telescope" method), from which pipes are deployed to heating devices, and from them to the return pipe, which goes in a parallel supply pipe in the direction from the boiler, collecting outgoing from Radiators water, and increasing in diameter (the same method "telescope") to the last radiator. At the same time, the length of the path passing through water is the same for all radiator contours.

The highways made by variable diameter are called the "telescope". This saves on the cost of feed and return highways, as well as increase the hydraulic balance of the heating system.

For example, for copper highways (soldering), it saves almost twice as much money on the pipes. Instead of 100 thousand rubles to pay only 50 thousand, there is a difference or not?

The dead-end two-pipe system with the counter movement of water in the supply and reverse laying pipelines and the two-pipe flowing system with associated water movement are shown for comparison in the figures below:

The boiler is indicated by the letter H, and the radiators are numbers.

We also want to repeat that the use of "backway" two-pipe CO (heating system), instead of "dead-end" CO, in many cases makes it possible to abandon the use of hydraulic (hydrotrifers), collectors and additional pumps.

Those. Just only a boiler pump. Those,, just, to use the pump of less power than it will be necessary for a dead-end two-tube, and even better it would be necessary for one-tube (plus a hydration with collectors would also be required for one-tube).

And it saves, at the cost of materials and the cost of mounting the heating system.

Question.

The boiler is still in the project, because Gas will be only in the next year, while the electrocott is hanging

One person advised the pipe 16th, on a one-tube, he says - will cope (the area of \u200b\u200bthe 2nd floor is 100 m sq. M).

Thank you! I want a good tube that it would be for a long time to lay and forget, the price is secondary. Hands from the collector grow normally

Answer.

My personal preference in your case (hereinafter the wall gas boiler, but not antiquity of the type AOGV, with non-working automation) PP tube PN25 SDR6 reinforced pipe, but only with solid aluminum (and not perforated and non-fiberglass) in the center of the pipe layer. Only if you stop at this option - do not believe the sellers that it does not require a cleaning for this type of pipe. A special end stripper and a special forces for a polypropylene welding machine is required. But it costs only 180 + 250 + 250 rubles, so not a problem.

It is just that, if you bore the technology and the aforementioned pipe to carry out the installation without a mechanical stripper and without special forces, but then the bundle and the arrival of pipes into disrepair arises.

hobo said:

Thank you! And the manufacturer PN25?

answer:

For heating, it is desirable to choose the pipe of the PN25 SDR6 brand.

I believe that the majority of pipes reinforced with fiberglass are not suitable for autonomous heating systems, due to oxygen permeability. For example, PN20 SDR7.4 - in its intended purpose for hot water systems. There it is good, but not for autonomous heating systems.

What makes oxygen with the components of heating systems - a well-known fact.

Another thing is that many European manufacturers have already begun the production of polypropylene pipes, although reinforced with fiberglass, but having a protective barrier for oxygen. Unfortunately, personally, it is not possible to evaluate how much this sprayed the finest layer of the barrier, effectively protects against oxygen penetration. Here as they say "can help, and maybe not." The desire to progress while the choice is dictated in favor of pipes reinforced in the center of the aluminum layer. Moreover, this layer of aluminum must be tightly tightly told pipes on the jack of aluminum jack. And not just made a mustache, as some pipe manufacturers are practicing now.

The sellers are individuals that with your heating system will be in a few years, and that you will have to change the heat exchangers of the boiler, and radiators and pipes. In short, do everything again. But it is impossible to blame the sellers in all. Well, they are not designers, in the end, but only sellers. You yourself already possessing the specification applied to the project, you need to know what you need. It is clear that we are not looking for a doctor for recently, what kind of medicines to buy, but the saleswomen at the pharmacy, but agree, this is only our delusion, and not the mistake of the seller's girl in the pharmacy.

P.S. I do with my own hands and nose (when PP is burning on the nozzles of the welding machine and leaves) I immediately feel high-quality or not polypropylene, the sense of fake and the "Palo" pipe. I work the fittings of the arquer, rose, well, if I don't find something from the desired range, then SPK (but unfortunately, in recent years, not very quality, but maybe the fakes are found).

And I prefer a dealership. Preferred by aluminum in the center of the layer I prefer the design group of Oxy plus (but the fittings do not like them). As in the future there will be the quality of these brands, naturally, I do not know.

Maybe there are other decent respect for the pipes of other productions, but you know, my choice is made on the basis of the assortment presented, in my region. All brands do not trust, and there are a lot of fakes.

Take only official dealers. This is the main thing. But not in network stores and not in building supermarkets and in building markets. It will help you to protect yourself from buying low-quality pipes and fittings.

Allmas said:

Just in the summer how to fuck ... Heated towel rails?

And how will the warm floor in the bathroom work in the bathroom?

Answer:

If you choose a booth boiler Moon 3 Comfort comfort, or another set of a boiler with an indirect heating boiler (BKN) having recycling, then heated towel rails (PS) and warm floors (TP) in the summer in the summer can be pulled out from the RVW recycling in the summer. This recirculation is still to you and much money will save, not counting the fact that you will not wait for a few minutes while hot water will go from the crane instead of cold.

Solto said:

recycling save? ..

could you confirm your statement on figures?

and it is not entirely clear about the TP, which are offered in the summer to put on the return of DHW.

Answer:

Regarding the savings on recycling.

1. We calculate how much time we are waiting, as long as hot water from the boiler or boiler will reach the mixer we open. In many houses from the boiler to the extreme points of water intake on the upper floors there are many meters of pipelines. And we still calculate what volume of water, while leaking into the sewer, while we will pay for excess water, and fill the gap of our septicch or a concrete cesspool, which you also need to empty the money.
2. After we have waited and consulted with hot water, the volume of water that we merged into the sewage, will cool down again. And the heating of this volume was spent or wasolars or gas or electricity. We will throw this money to the wind, every time you use hot water. And the next time everything is repeated in a circle. We will catch the same cool water into the sewer, and again we will wait until hot water goes from the mixer.
3. Taking into account the fact that as already wrote (from the boiler to a long bathroom) there can be a very high length of the DHW pipeline, we lose their nerves, comfort and time. And the time is also money. Calculate how many minutes the human life lasts. Not so much.

4. When recycling the pipe supply pipe and the diploma of DHW, with its full turning on their shirt made of foamed polypropylene (type 9mm energy flow), there will be quite a bit heat.

Regarding heated towel rails and "warm" floors.

1. There is no alternative to connecting a DHW recycling recycling through the PS. If only do electric PS. Electric PS 220 in the shower - for me extreme on the verge of suicide (there may be a deadly damage to electrotock easily). If not to do at all the PS in the bathroom, the black mold fungus will inevitably grow, where only you can and where it is impossible. And the smell of non-baking rags will always be in the bathroom. If you put an exhaust electric fan for ventilation, then, first, it acts on the nerves with its noise, and secondly, in the bathroom should be warmer than in the house, so that when they are sprayed get out of the bath or shower, then not We would have time to frozen before driving a towel. And the forced ventilation by the exhaust electric fan in the bathroom, leads to a drafts in the bathroom. That is, not knocking your teeth when leaving the shower on the breech. By the way, the norm of SanPiN on the temperature in the bathroom, which plus 25 degrees.

2. And it does not interfere with the recycling of the GVS recycling to plant the same collector-mixed knot of warm floors. Due to this, the warm floors will function not only in the heating period, and year-round. But where else to chain the mixing unit TP, so as not to include heating in the summer?

Allmas said:

Yes, the recirculation of the DHW would like, a comfortable thing and not very expensive.

If you can feed the TP by 11.2 square meters. m. in the summer it would be excellent.

I think it was necessary that there were TP that in C \\ at the first floor (one of the circulator's contours of the UCP) separately - you could run in the summer ...

Answer:

AND, This is already not to mention that the secondary heat exchanger of any two-kilt boiler compared to a bunch of a single-mounted boiler + BKN very quickly fails (and for some reason always in the frost, when the system is very easy to defrost. And the serviceman for boilers, during this period It is extremely difficult for repair to find. If only, for an astronomical amount, much greater than in summer).

Yes, and change due to the quality of the incoming cold water, every three years the heat exchanger will rise after a couple of repairs in the cost of a new two-kilt. Moreover, with each such repair, you will be forced to remain not only without DHW, but also without heating.

And also, not to mention savings on the DHW, and comfort at the expense of circulation, and the fact that in the summer in the summer you will not stand the smell of rotten rags, and there will be no black mold-fungus, extremely harmful to health.

Also with a "native bundle" boiler + BKN Hot water can never end, and you do not have to wash off my soap with icy water. Since the boiler is 32 kW, in a bundle with a native boiler (with a heat exchanger at least 24, at least 48 kW) works perfectly in flow-through mode. Therefore, BKN is not necessarily bought from 200 liters. It is enough, about 70 liters.

And one more extremely useful moment in the "native" bundle of the boiler with BKN. When taking a soul, you will not have to swallow Legionell from the DHW (smell like from a public toilet and in essence the same contents). You can simply program the boiler so that it takes the temperature in BKN at night in the night to plus 65. And this is to be recirculated every time it will be sterilized and the BKN and the entire DHW pipeline, to the recycling point.

Winter, frost dresses with windows windows with carved patterns ... Yes, it was sometime. Now rarely where you will meet such a phenomenon. Progress moves forward, people come up with something new to create convenience and a cozy atmosphere in the house. In this case, I am talking about sealed windows.

But what comfort can we talk about when in the house is cold and in the morning you don't want to climb from under a warm blanket? The picture is not pleasant. In this article, I will tell you how to correctly calculate the number of the radiator sections needed for the heating of the room so that it does not have to molten from the lack of heat in winter evenings.

Someone, as I happened to see one day, makes a calculation sharing the power of the radiator into square meters of the room - this is rooted incorrectly! It should be considered based on the number of cubic meters! The height of the ceilings in different homes can be different. Typically from 2.5 to 3m. And this is not a limit, because someone, for example, like high ceilings.

Without unnecessary theory is simply accessible.

So, we consider:
length - 5m,
room width - 3m,
height - 2.5m
accordingly, the volume of the heated air can be found alternating these quantities: 5 * 3 * 2,5 \u003d 37,5m3

The radiator who will suit us in height, that is, will be located under the windowson, the one whose height is 500mm. (You can be less). The documentation says that one section of such a radiator produces 145 W at Delta T \u003d 70 C.

145 W is enough to give up 3.6 m3 of the room. We have 37.5 m3. We divide the total volume - 37.5 m3 by 3.6 m3 and we get the number of sections you need.

37,5/3,6=10,417
Round, we get 10 sections of the radiator on the room.

If Windows 2, take two radiator for 6 sections, (if two windows, then most likely you have this angular room and heat again) if one window is one radiator for 10 sections.

What does Delta T "mean?

In physics, it is so accepted to identify the difference of any values, in this case - the temperature difference.

dT \u003d (T1 + T2): 2-T3
Where DT - Delta T, T1 is the feed temperature, T2 - the temperature of the return, T3 is the room temperature.

dt \u003d (95 + 85): 2 - 20 \u003d 70 °

That is, the temperature of the coolant (water) at the inlet to the radiator 95 ° plus The temperature of the coolant (cooled water) at the outlet of the radiator 85 °resulting from the result we divide on 2 and deduct the room temperature - 20 °.

In practice, this, of course, is unrealistic. No one is waiting for water in the radiator cool exactly 15 °. Circulation has been occurring. That is, Delta T for the radiator is a very conventional unit and in our case it is needed only to compare the characteristics of different models of radiators.

There is another important point! If your room is angular or under you a basement, or above you the roof, increase the required amount of thermal energy to the coefficient of 1.1 - 1.3. Personally, I believe that it is better to deliver an additional one section of the radiator. The overaction of heat is easily regulated by a thermostat or a conventional ball valve, but its disadvantage is made problematic.

Outcome:
1 section of the radiator with a capacity of 145 W is capable of measuring 3,6m3.
1 meter cubic leaves 40 watt power!
If the room is an angular one, then 1 meter cubic is already 44 - 52W
That's all the arithmetic!

What patterns are subject to changes in the temperature of the coolant in central heating systems? What is it - the temperature schedule of the heating system 95-70? How to bring the heating parameters in line with the schedule? Let's try to answer these questions.

What it is

Let's start with a pair of distracted abstracts.

• With the change in weather conditions of heat loss of any building, they change after them. In the frost in order to maintain a constant temperature in the apartment, much more thermal energy is required than in warm weather.

Clarify: The cost of heat is determined not by the absolute value of the air temperature on the street, and Delta between the street and inner rooms.
So, at + 25c in the apartment and -20 in the courtyard, heat costs will be exactly the same as at +18 and -27, respectively.

• The heat flux from the heating device at a constant temperature of the coolant will also be permanent.
  The drop in the room in the room will slightly increase it (again due to the increase in the delta between the coolant and air in the room); However, this increase will be categorically not enough to compensate for the increased heat loss through the enclosing structures. Just because the lower threshold of temperature in the apartment acting SNiP is limited to 18-22 degrees.

An obvious solution to the problem of growth of losses is to increase the temperature of the coolant.

Obviously, its growth should be proportional to a decrease in the street temperature: the colder outside the window, the greater the weight losses will have to compensate. What, in fact, brings us to the idea of \u200b\u200bcreating a specific approval table of both values.

So, the graph of the temperature system of heating is a description of the dependence of the flow of feed and return pipelines from current weather on the street.

How it all arranged

There are two different types of graphics:

1. For thermal networks.
2. For the domestic heating system.

To clarify the difference between these concepts, it is likely to start with a brief excursion to how the central heating is arranged.

CHP - thermal networks

The function of this bundle is to heat the coolant and deliver it to the end consumer. The length of the heat mains is usually measured by kilometers, the total surface area is thousands and thousands of square meters. Despite the measures for thermal insulation of pipes, heat loss is inevitable: having passed the path from the CHP or boiler room to the border of the house, technical water will have a partially cool.

From here - the conclusion: so that it reaches the consumer to retain an acceptable temperature, the supply of heating in the outlet of the CHP should be as hot as possible. Limiting factor is the boiling point; However, with an increase in pressure, it shifts in the direction of increasing the temperature:

Pressure, atmosphere	Boiling temperature, degrees on Celsius scale
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 the heating mains - 7-8 atmospheres. Such a value, even taking into account the pressure loss during transport, allows you to start the heating system in houses up to 16 floors without additional pumps. At the same time, it is safe for trails, risers and eyeliner, mixer hoses and other elements of heating and DHW systems.

With some reserve, the upper limit of the feed temperature is taken equal to 150 degrees. The most typical temperature graphs of heating for the heating mains are in the range of 150/70 - 105/70 (the temperature of the feed and reverse route).

House

In the home heating system there are a number of additional restrictive factors.

• The maximum temperature of the coolant in it cannot exceed 95 C for two-pipe and 105 s for.

By the way: in pre-school educational institutions a restriction of much more rigid - 37 S.
The price of a decline in the flow temperature is to increase the number of radiators sections: in the northern regions of the country, the rooms of groups in kindergartens are literally wounded by them.

• Delta temperatures between interpodule and return pipelines for obvious reasons should be as small - otherwise the temperature of the batteries in the building will vary greatly. This implies the rapid circulation of the coolant.
  However, too fast circulation through the home heating system will lead to the fact that the water of the breeding will return to the track with an exorbitant temperature, which, due to a number of technical restrictions in the work of the CHP, is unacceptable.

The problem is solved by mounting in each house of one or more elevator nodes, in which the reverse reverse is mixed into the stream of water from the feed pipeline. The resulting mixture itself, and provides a quick circulation of a large volume of the coolant without overheating the return pipeline of the route.

For domestic networks, a separate temperature schedule is specified, taking into account the scheme of the elevator. For two-pipe contours, the temperature schedule of heating 95-70 is typical, for one-tube (which, however, is rare in apartment buildings) - 105-70.

Climatic zones

The main factor determining the algorithm for drawing up the schedule is the calculated winter temperature. The temperature of the coolant temperature must be compiled in such a way that the maximum values \u200b\u200b(95/70 and 105/70) in the peak of frosts ensured the appropriate temperature in residential areas.

Let us give an example of an intrama schedule for the following conditions:

• Heating devices - radiators with coolant feed from the bottom up.
• Heating - two-pipe, co.

• Calculated outdoor air temperature - -15 S.

Outdoor temperature, with	Feed, C.	Filtment, S.
+10	30	25
+5	44	37
0	57	46
-5	70	54
-10	83	62
-15	95	70

Nuance: When determining the parameters of the route and the domestic heating system, the average daily temperature is taken.
If at night it will be -15, and during the day -5, it appear as an outdoor temperature -10С.

But some values \u200b\u200bof the estimated winter temperatures for the cities of Russia.

City	Calculated temperature, with
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

In the photo - Winter in Verkhoyansk.

Adjustment

If the parameters of the track meets the management of the CHP and thermal networks, the responsibility for the parameters of the domestic network is assigned to housing. The situation is very typical when, during the complaints of residents to the cold in apartments, measurements show deviations from the schedule to the lower side. A little less often it happens that measurements in the wells of thesis show the overestimated temperature of the repetition of the house.

How do you bring the heating parameters in accordance with the schedule?

COMPLEING SOZLY

Under the low temperature of the mixture and return, the obvious solution is to increase the diameter of the nozzle of the elevator. How it's done?

Instructions - to the reader.

1. All the valves or valves are overlapped in the elevator node (input, house and DHW).
2. Elevator is dismantled.
3. The nozzle is removed and drilled by 0.5-1 mm.
4. The elevator is assembled and started with air blending in the reverse order.

Tip: Instead of paronite gaskets on the flanges, you can put rubber, carved in the size of the flange from the automotive chamber.

Alternative - installation of an elevator with an adjustable nozzle.

Jumping sucking

In the critical situation (severe cold and freezing apartments) nozzle can be completely removed. So that the subsicing does not become a jumper, it is shuffling a pancake from a steel sheet with a thickness of at least a millimeter.

Attention: this is an emergency measure that is used in extreme cases, since in this case the temperature of the radiators in the house can reach 120-130 degrees.

Adjusting the difference

With high temperatures as a temporary measure before the end of the heating season, the drop in the elevator is practiced.

1. DHW switches to the feed pipe.
2. A pressure gauge is installed on the return.
   
3. The input valve on the return pipe is completely closed and then gradually opens with pressure control on the pressure gauge. If you just cover the valve, cheek drawdown on the stem can stop and defrosting the contour. The difference is reduced by increasing the pressure on the return on 0.2 atmosphere per day with daily temperature control.

Conclusion