Open heat supply system

The construction of a private house, and especially if it is carried out independently - this is a long series of solutions to a wide variety of problems. And one of the most important is providing in the future building of the most optimal living conditions at any time of the year( unless, of course, the house is planned only as a summer dacha).

And already in this area of ​​creating the necessary microclimate in the premises the most difficult task will be the correct calculation and installation reliable heating system. Despite the emergence of modern electric heating systems at home, leader for purity and demand remains water heating - it is more familiar, time-tested, its installation and debugging techniques are worked out to the smallest detail. The owner of the house that chose the water heating remains to decide on a particular type - closing or open heat supply system, with its "hardware filling" and with a system of piping in the house. Then there are the stages of careful design and installation.

Among numerous publications on this issue, posted on the Internet, you can find many of those in which it is stated that an open heat supply system is extremely simple in the device and its can be mounted literally in one day. If the reader gets such "art" - you can without any regret reading to interrupt and close the page - the author clearly does not have any idea, about heating in general , nor about open system - in particular. Any system must be properly designed with account m m number of nuances, well balanced, reliably mounted - and these tasks are absolutely simple and fast in the performance is not call .

What is the open system of heat supply

First of all, you must immediately make one important note. Very often, when describing an open heating system, the authors all the facts "get in the way", presenting it necessarily as heating with a natural circulation of the coolant. Nothing like this! The open system can be both with the natural and forced circulation of the liquid, with with the competent design of the host in in . Now it is possible to switch easily and quickly from one mode to another.

The main feature of the open system is the absence in of its circuit of any artificially created excess pressure, as it is directly related to the atmosphere. In the system, an expansion tank is necessarily assembled, the free volume of which is designed to compensate for the expansion of the heat transfer fluid with increasing temperature. Such a tank is always located in the of the highest point of the entire heating circuit piping. Thus, still has the function of the air vent - all gas accumulations in the pipes must come out right here. It also serves as a kind of water gate - a layer of liquid coolant, which always must be in the expansion tank, prevents air from entering the system from the outside.

It is worth considering such a system in more detail:

1 is a source of thermal energy, boiler , operating on type of fuel( solid , liquid, gaseous) or using electric energy for heating.

2 - rising from boiler riser, which rises to the highest point of the system and very often in this place ends with an expansion tank. There may, however, be other options for location - this will be discussed later. The main thing is that the pipe of the largest diameter in the system is always used for this riser - this helps to ensure the necessary pressure difference in the supply pipe.

3 - expansion tank of open( atmospheric) type. In this position, both a special tank produced by industrial enterprises can be used, and, in principle, any capacity suitable for volume . So, metal reed drums, milk cans , gas cylinders and are often used.

4 - so that the overflow does not happen in the expansion tank, always does on the with the level defined on the level by a pipe outlet, which will take excess water to the sewer or simply outwards, to the ground. In principle, in a well-tuned heating circuit such overflows are a rarity . and more often this outlet pipe will be used to control the filling of the entire system, and for a primary reset.

5 - pipe, supplying the heating medium to the radiators( radiators).In open systems such as , , even if the provides for the installation of a pump, the pipes must have an defined slope to ensure natural circulation of the fluid. Piping can be different - this will be discussed below.

6 - Heating appliances located in the premises of the house - radiators for heating. Convectors or, for example, "warm floors" with an open system are usually not used. The layout of the radiators can be different - it is connected with defined by the piping system.

7 - Reverse pipeline - providing the flow of coolant from the radiators to the boiler for further circulation.

8 - circulating pump. The system can do without it, working on the principle of natural circulation, the however pump sharply raises the efficiency of heating, reduces the energy consumption.

9 - valve( valve) for primary filling and periodic replenishment of the heating system from the water mains( 10).In the normal position is always in a closed state.

11 - valve( valve) for draining the coolant from the heating system, for example, to perform any repair or maintenance work.

• Now, after the device of the open heating system, a little more in detail - about the principles of its action.

If there is a pump in the system, then there are no special questions - it creates forced coolant circulation through the pipes. But how is the heat transfer in the circuit not equipped with pump, or in the absence of electricity, when the unit is switched to natural circulation?

Here the laws of thermodynamics come into full force. Remember a simple example - why in the water body the water is always warmer at the surface, and much colder - as the depth increases? The answer is simple - and with gases, and with the fluid there are approximately the same phenomena - increasing their temperature( in conditions of free volume ) leads to a decrease in their density, and therefore - the total mass. In a word, a heated liquid or gas is always lighter than cold ones.

Now attention is drawn to the scheme:

In the heating system, on the large account , there are two types of heat appliances that work as a counterbalance to each other. boiler( item 1) is the first accurate heat transfer - converts energy from an external source to a thermal source - heats the water. Then idea t t transporting the coolant to the second main heat exchange point - radiator( pos.3). It is clear that in the supply line( in the figure - the red area, poses .2) the water density Pg is significantly lower, than on the opposite site( blue area, poses . 4).Higher fluid density Rokhl means its "predominance" in terms of gravity processes - it is simply much denser and heavier. If two heat exchange points are correctly positioned relative to each other, and in particular heat transfer devices placed above the boiler on the h , then a natural circulation current of the liquid will necessarily be created. At the bottom of the circuit, this is clearly visible. The region with the low-density coolant is conditionally "removed"( it can not prevail over the denser one).There are two communicating vessels, one of which is higher than the other. Water tends to balance, and constantly flows from the radiators to the boiler.

So, in order to create a natural movement of the coolant, the boiler should be located below the lowest radiator in the house. This value of h can be different( the higher it is, the more fluid the fluid will be), but it should not exceed 3 meters. Most often, if there is such an option, the boiler room is located in the basement or in the basement - this is most convenient, since the required excess of radiators in the rooms of the ground floor above the boiler is fully provided.

If there is no basement in a private house, then it is necessary to make a boiler room in the extension, slightly deepening the floor in the installation point of the boiler. If this is not possible, then for the creation of an open type heating system, there is no need to take it - it will not work in the natural circulation mode, and it would be much more logical to use the scheme with an accumulating tank-receiver at once.

• It can be noted another one important property of an open heating system, running in natural circulation mode . speech comes about a kind of self-regulation of the flow rate of the coolant in the pipes. Unlike from from option with forced circulation, the flow rate of the liquid through the pipes here is very is unstable.

When starting the boiler and warming up a certain amount of liquid, begins its natural current through the pipes. Characteristically, in order for to make such motion began, the boiler needs to be briefly started at a power close to the maximum - so that the overcomes the inertness of the water and the existing hydraulic resistance in the pipes.

While the rooms are not warmed up, the amplitude of the temperatures in the boiler and at the outlet from the radiators is the maximum. So, the greatest difference is in the density of the coolant, and means , as we have already found out - and the intensity of fluid movement along the contour. As the temperature warms up, this difference begins to decrease. That is, the rate of movement of the coolant gradually decreases.

As a result, with certain stabilization of the system, the water flow is slow enough - but this is enough to maintain the desired comfort temperature in the rooms( usually with the specified by the user on the boiler controls).However, if there is a sharp drop in temperature in the room, for example, with open windows or when it is cold outside, the fluid flow spontaneously accelerates - the system will strive to achieve equilibrium.

Advantages and disadvantages of open

open heating system The open heating system is definitely not "perfect", and has a lot of serious deficiencies. However , some hosts housing choose this particular scheme, motivating its solution its advantages:

• Reliability - probably the main plus of such a heating system. The scheme is thoroughly tested, has passed all conceivable tests in a variety of conditions and has fully proved its effectiveness. On a large account , in a system with natural circulation there is simply nothing to fail( if you do not take calculation in itself, boiler ).The term "life" of such heating is determined exclusively by the operational life of pipes and radiators - with a competent selection of components this will be calculated in many decades.
• The circuit is quite simple to install, it does not have particularly complex components.
• This system does not require any specific debugging and configuration. It is enough to fill the system with water and turn on the boiler . principle boiler is turned on - the system is running, off - the current has stopped.
• When working without a pump - no vibration whatsoever and characteristic noise .
• Nothing hinders to supplement the system with a circulation pump - then it will get full versatility. With the pump, of course, the losses on heating will be less, but in the case of lack of electricity or when the pump breaks down by simply switching the valves, the heating is transferred to a completely non-volatile regime.

The diagram shows the position of the valves when operating in forced circulation mode - both valves pos.1 are open, and the one standing on the main pipe( item 2) is closed. To switch the mode, simply change the position of the valves to the opposite.

• Already mentioned property of system self-regulation allows to sustainly maintain a given microclimate in the room without any complicated additional regulating devices.

Now - about the disadvantages of an open heating system:

• Such a system is simply impossible to put in a very large house. When remoteness of is about 30 meters from the boiler( horizontally), the hydraulic resistance in the pipes can exceed the naturally created pressure and a static balance will be created in the circuit - this is unacceptable for heating.
• The system is very inert, that is, it enters the working state long enough. This is due to the need to create a natural water flow, and a very large volume water in the heating circuit.
• There are certain difficulties with the acquisition of the material - I will need t t different diameters, adapters to them and , etc. .A pipe of large diameter - it more and a lot of money.
• When installing the system, a slope must be created on all sections of the pipelines - from the feeder and to return , without exception. This should be taken into account when designing and assembling the installation drawings. If for some reason a bias can not be created at a certain site, heating may prove to be ineffective or excessively "wasting" on the part of the energy expenditure - certain part its will be spent on overcoming unnecessary gravitational and hydraulic resistance on the straight segment of the system.
• The need to install a surge tank at the highest point often leads to the fact that it has to be installed in the attic. This means the need for its most careful thermal insulation to prevent freezing in the peak winter cold.

. However, some masters find an outlet by placing the expansion tanks directly in the room, fixing them close to the ceiling or even in general - on the ceiling itself. From the point of view of the aesthetics of such a solution - the question is, of course, extremely controversial, but the problem of thermal insulation is solved immediately.

• An open heating system is always accompanied by a gradual evaporation of the coolant - it is necessary to constantly monitor its level. Sometimes this issue is automated( on the basis of the float valve ).Another variant of the evaporation control is an oil layer, thickness of 10 - 15 mm on the surface of the water in the expansion tank( of course, it is added only when the complete equilibrium in the system is reached).However, in this case, the possibility of oil entering the lower pipes, radiators and boiler ( for example, at some accident falling, water level) is possible, and this is highly undesirable.
• Contact t t The carrier with air means its constant saturation with oxygen. This leads to activate corrosive processes in pipes, fittings, radiators, in other metal components of the circuit.

Video: basic principles of the open system heating

Elements of the open heating system

Above the text, all the mandatory constructive and technological \ elements heating systems of the open type have already been listed. It is worth considering them in more detail:

Boiler

First of all, you need to determine the required capacity of this source of thermal energy. It would seem that you can take boiler "with a reserve", however, practice shows that the excess capacity, in addition to the rise in the price of the unit itself, has more a few negative points:

• There is a marked condensation in the chimney channel.
• Rapid wear and breakage of accessories is not excluded.
• The boiler can not work effectively - it simply is not designed for operation "at low revs".
• Cases of automatic failures are quite probable - for the same reason.

So, boiler should be necessary, but not excessive capacity. This parameter can be determined using the following formula:

M k = Σs × Ms / 10

M k - rated power of the required boiler;

Σs - the total area of ​​the heated premises of the house;

Ms - Specific power required for heating per unit area

The specific power factor is a differentiated value, depending on the region in which the house is built. The approximate value is indicated in the table.

The region of Russia in which the construction of the	is underway. The specific power( kW) per 10 m ²
Southern regions of the country( North Caucasus, Caspian, Priazov, Black Sea regions)	0,7 ÷ 0,9
Central Chernozemie, Southern Volga Region	1, 0 ÷ 1,2
Central areas of the European part, Primorye	1,2 ÷ 1,5
Northern areas of the European part, Urals, Siberia	1,6 ÷ 2,0

Example: calculate the boiler output for a house in the Voronezh region,with a heated area of ​​180 m².

M k = 180 × 1,2 / 10 = 21,6 kW

This value is rounded up, according to the standard value of the heat plants available in the production and sale. However, there are more three disclaimers:

• This formula is valid for rooms up to 3 meters high. However, in a private house few people allow themselves to make ceilings higher.
• The calculation of is only valid provided that the house - walls, windows, doors, floors and , , are benign.
• Similar to , the calculation applies exclusively to the heating circuit. If there are plans to connect to heating, for example, an indirect heating boiler, it will be necessary to increase the rated power of the by another by a quarter.

When selecting a boiler, you can go to other by .Many manufacturers with their own dealer offices in different regions provide services for the exact calculation of the of the required equipment. Often, such firms have their own sites, which have convenient and understandable calculators that allow you to quickly perform calculations for by entering data on the area of ​​rooms, ceiling height, wall material, type of doors and windows, the need for a hot water circuit and .As a result, the program will give the optimum capacity of the boiler for installation in a particular house.

Calculator for calculating the required heat output of the

boiler. In a somewhat simplified but accurate manner, a similar program is presented on our portal. It allows you to calculate the heat demand for each room. Summing up the values ​​obtained, it is not difficult to determine the total required power for the whole house.

For convenience, you can create a table, which immediately enter the parameters of all rooms. For example, this:

Area, m²	External walls, number, are on:	Number, type and dimensions of windows	Outside doors( on the street or on the balcony)	Result of calculations, kW
TOTAL	22,4 kW
1 floor
Kitchen	9	1, South	2, double glazing, 1,1 × 0,9 m	1	1.31
Entrance hall	5	1, Ю-З	-	1	0.68
Dining room	18	2, C, in	2, double glazing, 1.4 × 1, 0	no	2.4
and so on
2nd floor
Children's	. ..	. ..	. ..	. ..	. ...
Bedroom 1	. ..	. ..	. ..	. ..	. ..
Bedroom 2	. ..	. ..	. ..	. ..	. ..
and so on

Having a plan at home and presenting the features of the premises, filling in the boxes will not be difficult at all. And then it remains only to calculate the thermal power for each room and find the amount. It takes literally minutes:

Which boilers can be used in an open system:

• If in the inhabited point gas mains, then there is nothing special to think about - for today day similar heating remains the most profitable in terms of the cost of energy.

There is, however, a significant "minus" - required concordant procedures, drawing up the corresponding project and its implementation with the involvement of specialists( employees of gas utilities tv pr Actively ubiquitous are"Monopolists" for such work and no one is entrusted to them).This all will cost a fairly "weighty" amount. However, this is a one-time investment, which should pay off after some time.

• The solid-fuel boilers remain popular, and in some regions where there are no problems with logging or buying coal, they remain the most popular among house owners.

Now it is no longer old cast iron "giants" absorbing a lot of fuel and having extremely low efficiency .The modern solid-fuel boiler is usually an aggregate of long burning, which does not need constant monitoring after it. More about such boilers - in a special article of our portal. By the way, there you can find a lot of tips and how with your own hands make the necessary solid boiler heating using the function afterburning pyrolysis gases.

• Electric boilers in open systems are used infrequently. What is a sin to conceal - a similar system still loses in efficiency to a closed system. What is acceptable when using inexpensive energy carriers - gas or wood( coal), will result in a "good penny" at change in electrical heating. With some degree of conventionality, you can apply induction heating, but again - it's better then immediately mount closed system, which much lighter lends itself precise adjustments.

But the electrode boiler in an open system can not be used in principle - it requires a special and stable chemical composition of the coolant. It is simply impossible to observe this condition in an unsealed circuit.

• Optimum in functionality, though quite expensive solution, the acquisition of a multifunctional, combined boiler that can operate in different modes. For example, there are models " firewood + gas", "gas + electricity", firewood + coal + gas, or even firewood + coal + diesel + gas.

Expansion tank

As already mentioned, this element can be purchased ready-they are on sale , or made independently of a metal sheet, or from the existing metal capacity.It is better to use metal that is not subject to corrosion - then the heating will serve for a long time.

. When manufacturing the simplest tank, it is necessary to provide a hinged or removable cover - it will allow to control the water level in the system, but in the closed state it minimizes the evaporation of the liquid.

In the upper part of the tank, a branch pipe must be installed, along which, in case of excess liquid, it will drain down.

It is considered sufficient if the volume of the expansion tank is approximately up to 10 % from the total volume of the heating system.

By the way, the installation of an open-type expansion tank right above the boiler at the highest point is by no means a dogma. Such a scheme is good, however, it is by no means always possible to perform simply for reasons of non-compliance with the real location of the technical premises of the building.

The figure shows several different options for placing the expansion tank, which can be chosen the most appropriate to the existing conditions.

It is noteworthy that in the case of installing a surge tank on the return pipe, all will also require the mandatory installation of the airway valve in the of the highest system point( not shown in the diagram), and this is unnecessary additional complexity.

Heating Radiators

If boiler is the main element in the part of obtaining thermal energy, then the radiators are the main ones for its "distributing" for substitutions. And this means that it is very important to determine exactly, in the which room, of which and how many they need to be installed.

To begin with , you need to determine the type of radiators. They differ both constructively, and on a material of manufacturing, and in total - on the operational characteristics.

• Traditional cast-iron batteries are excellent for open heating systems. Yes, they are quite inert in heating and cooling, but this is even good in combination with the similar properties of the open circuit - this "" complex can not be adjusted very precisely, but the savings on such inertia can be achieved quite impressive.

Often blamed for such batteries for excessive massiveness and for a non-aesthetic appearance. Well, is first , it's possible to argue about the kind - modern cast-iron radiators are very pretty, and some are simply decoration of premises. And secondly, about massiveness - it's more of a dignity, if, of course, correctly solve the issue of their reliable mount.

• Steel radiators are inexpensive, lightweight, long-lasting( if they have a high quality anti-corrosion coating).

It would seem that it's a good option, but for an autonomous heating system, especially for an open system, it's better not to use them. The fact that they quickly give up heat and cool down - boiler with such radiators will turn on very often.

• Aluminum radiators - today are in the lead among the "fellow".They are light, durable, very simple and quick to assemble. They have excellent heat dissipation and the required heat capacity .Well fit in any interior.

They have a disadvantage, and considerable - this metal is very unstable to oxygen corrosion. Hence, or aluminum radiators with a special anti-corrosion coating are needed( such ones are available, but they are certainly more expensive), or the coolant must be of a certain quality. Unfortunately, it is almost impossible to observe the second point in an open heating system.

• Bimetal radiators are the most modern variant, combining all the best qualities. There are practically no shortcomings, except for one - a high price. Such radiators are well suited for heating with high pressure in the circuit, since they easily install electronic or electromechanical thermostats that maintain the exact temperature level in the room.

Alas, with an open heating system, this option remains unclaimed, and you need to think very carefully whether it is worth overpaying for such batteries.

The second question is how to determine the required number of sections in the heating battery. Everything depends on the size of the room, its features, and the specific power of each section of the radiator.

So, for the average rooms ( residential, with a ceiling height of 2.5 ÷ 3 m ) usually take the standard heating power equal to 41 W / m3 volume premises. Thus, it is easy to calculate the required total power by multiplying with the ( product of the length, width and height of the room) by 41.

For example, the room is 3.5 × 6 × 2, is 7 m . The volume of the is 56.7 m³. The required basic power of the radiators is 2325 W or 2.33 kW.However, it was not for nothing mentioned that this power is basic. She calculated the on the room inside the building with one external wall and one window on the street. If conditions are really different, then some corrections are needed to this value - see table.

Room features	Correction to the value of total heating radiators
Corner room: two external walls and one window	+ 20%
Corner room: two external walls and two windows	+ 30%
Windows face north or north-east	+10%
Radiators are hidden in niches under the windowsills	+ 5%
Radiators are covered with decorative screens or grilles	+ 15%

Let's say that in the example we are examining, a corner room with one window facing north and radiators in a niche. This means that 20% for the angular location, 10% - for the north and 5% for the location of the battery under the window should be added to the obtained value. The total correction is 35%, and the total power is 3.15 kW.

Now it is necessary to divide the received value into the specific power of one section of the radiator. This indicator is necessarily indicated in the technical characteristics of any model of radiators( in the case of steel non-separable radiators - the power of the whole unit is indicated).

Suppose, in our case, the installation of bimetallic radiators " Rifar " with the specific power of the section in 204 W is planned. The simple division of the gives the 15, 44, or a rounded of 16 sections for the normal heating of the of this , a sufficiently large and cold room.

We translate to take advantage of the capabilities of our special calculator, which will help quickly and accurately calculate the required number of radiator sections for the room:

Calculator for calculating the parameters of the radiators

Place the radiators most often in traditional places - under the windows where they createeffective thermal curtain from penetrating cold air. If necessary, it is possible to supplement such installation with additional batteries on other walls of the room - so that the required number of sections is obtained in total.

Circulation pump

As already mentioned, a well-assembled system can work without forced circulation. Nevertheless, if possible, the pump with should be installed - it will significantly reduce operating costs and increase the efficiency of heating. Yes, this device consumes certain amount of electricity comparable to the average incandescent bulb, however these losses are fully compensated by the economy on the consumption of the main energy carrier.

heating system

Pumps are not all the same. Even visually it is noticeable that they differ significantly in their technical characteristics. It's not about the diameter of the pipe, which is cut-in - the main parameters will be the performance of the device and created by the liquid head. These characteristics of the pump must correspond to a particular heating system, and means - you need to be able to conduct at least the simplest calculations of .

1. The desired pump performance can be calculated using the formula:

G = M k : ( Δ t × C t )

G - calculated parameter, the performance of the circulation pump

M k - capacity of the heating system( as it is calculated, it was told, in the article in the section on the boiler).

Δ t is the difference in the temperatures of the coolant at the inlet to the boiler and at the outlet from it. For conventional heating systems adopted at 20 degrees. For " warm floors" or convector heat exchangers may be smaller, but similar schemes in an open heating system are not used.

Ct - coefficient, taking into account the specific heat capacity of the heating fluid. It is calculated by several parameters, however large accuracy in this case is not required. Since in the open heating system in the majority of cases ordinary water is used, this coefficient can accept for 1.16.

For an example, what kind of performance would a pump require if the total power of 21.6 kW is required for heating the housing:

G = 216 00 /( 20 × 1.16) = 931

The value obtained is expressed in kilograms per hour. For convenience, it remains to bring it in the used value - m³ / hour. For this, it is necessary to divide the obtained value by the water density at a temperature of about 60 - 80 degrees( 972 kg / m³ )

As a result, we get:

931/972 = 0.96 m³ / h, rounded - 1 m³/hour.

Calculator for calculating the required pump capacity

2. The second important parameter of the pump is the amount of liquid created by it, which should ensure a normal movement of the coolant along theto this branched circuit. For the , the calculation uses the following formula:

Hn = r × L × Zr

Hn - pump-generated water pressure( in pascals , Pa )

r is the specific hydraulic resistance of the straight pipe section( Pa / m).With some assumption for a typical private house, you can take for 150 P / m.

L - the length of the entire contour, including the feed pipes and return .

Zr - correction factor, taking into account the equipped with heating system with additional shut-off valves and regulating devices. With an open heating system, this coefficient can be taken as 1.3 - the system is not supersaturated by cranes.

If, for example, the length of all pipes of the heating system in the house is 90 meters, then it is not difficult to produce calculation of :

Hn = 150 × 90 × 1.3 = 17550 Pa = 17.55 kPa .

Very often in the technical documentation this value is given in meters of water column. It is easy to translate, knowing that 1m is in .≈ 10 kPa .In our example, the pressure is obtained 1, 8 m water column.

Calculator for calculating the pressure of the circulation pump

Pipes and wiring diagrams

In the installation of the system, both the pipe material and the diameter and the circuit of them are importantwiring.

• Metal, steel pipes today, for a large account , are considered as survivals of the past .They are heavy, require special skills and special equipment for installation. Yes, and the cost of the metal, even ordinary steel - is very high, not to mention stainless steel.
• Copper pipes on the heating system are certainly very high quality and are reliable , but the high price of the material immediately makes it an object of peculiar luxury.
• Metal-plastic pipes can be used completely, but only if it is a quality, tested material. The disadvantage is that such pipelines should not be walled in - they should always be in sight because of the insufficient reliability of the metal fittings of connections - they can be oxidized or need periodic lifting.
• A more modern version is cross-linked polyethylene pipes( PE-Xa, PE-RT), and the is better than the - with metal reinforcement and an oxygen barrier( for example, PE-Xc /Al/ PE-HD).Among all modern materials of this category, such pipes are the most reliable .They are used even for warm floors, pouring screed and not worrying about safety at all - all the more they are suitable for external heating risers. A convenient system of connecting fittings makes the installation of such pipes easy and quick.

• And the most inexpensive option is polypropylene pipes. If you buy a quality material, with fiberglass reinforcement designed for high temperatures, then reliability of such pipes will suffice with excess for many years. And the installation, although it requires a special welding machine, is simple, and can easily be mastered by any average domestic master. The device for working for a very reasonable price can be rented in a specialized store.

Scheme of spreading pipes of the heating system is a lot - each of them has its advantages and disadvantages.

• For example, the single-pipe system is easy to implement and will require a minimum amount of materials. For open type heating with natural circulation, it is almost nor the ideal option.

Disadvantage: from radiator to radiator the temperature drops noticeably, which means quite uneven heating of rooms - most remote from the room boiler will be heated worse. However, if the heating is installed in a small and compactly planned house, then this scheme will be fully justified.

• The two-pipe system will require more careful planning and significantly higher pipe consumption. But evenly heating, with proper selection of the diameter of the pipes, significantly improves, and additionally , there is the possibility of temporary or permanent disconnection of from premises, which in it on for some reason at the moment do not need.

• The most convenient, but also the most difficult in execution is the collector wiring diagram - to each heating device( or sometimes to the instrument cluster) comes the own supply from the common collector. True, the costs of materials in this case are maximized. In systems of an open type, this approach is practically not applied.

The horizontal sections of the pipelines are very important for the correct circulation of the coolant. The usual recommendation is not less than 1: 100( 1 cm of height difference for 1 linear meg trd decrease).However, very often experienced masters give advice such an inclination to increase even up to 3 cm per running meter - this will provide the with reliable and stable natural circulation if there is a need to switch to on it .

AND, finally , the diameter of trd ub also is not a single value for the entire wiring of an open heating system. The maximum diameter is always on the feed pipe rising from the boiler to the expansion tank. Further, goes gradual tapering , so calculates so that by varying the diameter ensure uniform distribution of fluid flows through the heat exchange points.

The diagrams below show a few ready-made, professionally-calculated options, indicating the conditional diameter of the pipes( in inches).One of these schemes can be taken as a basis for designing your own system.

Accurate calculation t t required wiring for a particular building, with considering of all system parameters, can only conduct by a qualified specialist."Self-initiative" in this matter is quite dangerous because without taking into account any minor details , it is possible to get completely "locked" static sections of the heating circuit, the circulation of the heat carrier can not even be provided by a circulating pump.

Video: a variety of heating systems in a private house