Heating how to install a circulation pump. Heating pump connection diagrams: installation options and step-by-step instructions

Not so long ago, when the acquisition of high-quality pumping equipment for an autonomous heating system of a private house was a huge problem, preference was given everywhere to schemes with natural circulation of the coolant. However, despite the seeming simplicity of this approach, such systems are not highly efficient and economical. In addition, the possibilities for precise temperature control in individual rooms of the house are significantly narrowed, and with many modern heat exchange devices and systems, this type of organization of coolant transfer is not possible at all.

Yes, and the declared ease of installation of a circuit with natural circulation is also very conditional, since it requires obligatory observance of the slope, a strictly specified arrangement of devices, and the pipes themselves must be of increased diameter. Sometimes, in the conditions of a particular building, compliance with all existing mandatory conditions for ensuring normal circulation becomes a difficult or even impossible task. All of these problems will help to solve the installation of the pump in the heating system of a private house.

It is this block of questions that will be considered in this publication. It can be divided into several main subsections:

• What is a circulation pump for, and what are the advantages of installing it?
• How is the circulation pump for the heating system arranged?
• How to choose the optimal model?
• Where is the best place to install?
• How to independently carry out installation work?

Prices for circulation pumps for heating

circulation pumps

Advantages of a heating system with forced circulation of the coolant.

Ardent supporters of heating systems with natural circulation of the coolant give a number of seemingly irrefutable arguments in favor of just such a scheme.

• The pump is an extra cost for the purchase and installation.
• Any electrical equipment becomes an additional consumer of expensive electricity.
• The dependence of pumping equipment on the stability of the power supply makes the heating system extremely vulnerable in emergency situations in the power grid.
• The pump is an additional component of the system, vulnerable to mechanical breakdowns.

It would seem, at first glance, that everything is fair. But if you look at it unbiasedly, on each point, then the picture changes literally to the exact opposite.

Let's look at the scheme of the heating system with natural circulation:

Is such a scheme so easy to install and cheap? Not at all!

From the boiler (pos. 1) it is imperative to mount an accelerating vertical section (pos. 2), from a large diameter pipe - preferably 1½ inches or even more. At the same time, it must reach the highest possible point - above any heat exchange devices. In the same place, at the maximum height, you will have to install an open-type expansion tank (pos. 3).

The supply manifold (pos. 4) must be located with a mandatory slope of at least 5% (5 cm per linear meter of the circuit). In this case, again, the diameter of the pipe should not be less than 1¼ inches.

Vertical risers (pos. 5), through which the coolant is supplied directly to the heating radiators (pos. 6), are made of pipes with a diameter of at least ¾ inch.

Finally, the requirements for the diameter and observance of the slope of the "return" collector (pos. 7) are the same as in the supply pipe. It turns out that in any case, the boiler should be below the lowest-lying radiators.

In a small building, with compactly located rooms, such an approach is still feasible, and even then - not always. Large diameter pipes, not only are they much more expensive, but are more difficult to install. They are extremely difficult, often - and it is completely impossible to hide so that they do not spoil the interior. The possibility of a hidden lower connection of radiators is almost completely excluded. The cost of the pump itself and its installation (which can be done independently) are simply incomparable with the costs listed above.

Even with the most thoughtful, optimal placement of all elements of a circuit with natural circulation, it is hardly realistic to create excess pressure in it only due to temperature changes and a difference in density above 0.6 atmospheres. And such pressure will be clearly not enough for many modern heating devices. Moreover, you don’t even have to hatch plans to create a water floor heating system.

Moreover, even a slight blockage, somewhere on pipe bends or in another area vulnerable to this phenomenon, can completely paralyze the movement of the coolant through the pipes. And this will be all the more likely if the system is sufficiently branched, since hydraulic resistance will also have its say.

In order for a system with natural circulation to reach its design capacity, a powerful starting energy “impulse” is required. These are extra costs of energy carriers, and quite considerable ones at that. Well, even a short-term stop of the boiler for one reason or another will require both certain efforts and considerable time to bring the heating system back to normal operation. The low speed of the coolant and the expenditure of part of the energy generated by the boiler only for its movement is a general decrease in the efficiency of the entire system. And, believe that these extra energy costs will certainly exceed the total consumption of a compact circulation pump operating at a constant load.

A low circulation rate is also a clearly uneven heating of heat exchange devices installed in such a circuit and spaced apart in the rooms. Adjusting the level of heat transfer from radiators installed in the premises of the house becomes possible solely on a quantitative basis, that is, by changing the volume of liquid passing through the devices. This method is not accurate, and under conditions of low pressure in the pipes, it can even lead to blocking of one or another radiator or section of the circuit. Talking about high-quality adjustment in such conditions, that is, with the admixture of coolant from the return, is generally naive.

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The result is the same - the inefficiency of the system directly negatively affects the efficiency of energy consumption, that is, it leads to unnecessary costs during the entire period of heating operation. It is more profitable to spend money on the pump once already ...

Finally, a few words about the vulnerability of pumping equipment from the presence of power.

This is true, but in exactly the same way all electrical appliances in the house are dependent. Including - and the majority of modern heating boilers equipped with automation. The problem is solvable - it is enough to install an uninterruptible power supply for the boiler equipment.

With low pump power consumption, not even the most expensive and powerful UPS is able to keep the equipment running for several hours. This is quite enough.

And finally, nothing prevents you from mounting the pump so that in emergency cases it remains possible to switch to natural circulation in the system. This is usually what they do - the pump piping circuit includes a bypass (jumper) and several valves (an automatic valve can also be used).

Well, about the fact that the pump becomes another vulnerable link in the system. You can reassure the reader: statistics show that the failure of circulation pumps refers more to casuistic situations, they are so rare. The designs of devices from leading manufacturers are distinguished by excellent reliability and can serve for decades, unless, of course, the operating rules are violated. And the resulting benefit in the form of cost-effective operation of the system justifies the purchase of even an expensive pump in two to three years. So from this side, “expect a dirty trick” is the least of all.

We hope that the reader is convinced of the need to install a circulation pump. So, it's time to consider how to choose the right one.

How to choose the best circulation pump

Two main types of circulation pumps

Circulation pumps are devices powered by electricity. But direct contact of the electrical part with the hydraulic part is unacceptable. This division is provided by two approaches to the arrangement of devices, which predetermines their subdivision into “dry” and “wet” type devices. Much becomes clear from the title.

• Pumps with a "dry rotor" appeared before their counterparts. Their principal scheme is such that the electric drive is completely isolated from the pump part, and the rotation is transmitted to the impeller through the shaft. Even outwardly, such pumps can be distinguished by an elongated housing, due to the remote motor unit. As a rule, such devices are quite massive, so their console installation is most often practiced - for this, brackets or mounting pads are provided on the case.

"Dry" type circulation pumps are powerful and productive devices that provide both a very large flow rate of the coolant passing through them and high pressure indicators in the system. It's hard to do without them. If a powerful boiler house is being designed, for example, for a large mansion with several floors. But in the conditions of an apartment or a private house of medium size, their use is already seen as redundant, especially since they have certain disadvantages.

- About the difficulties associated with the overall dimensions, massiveness and features of the installation - it has already been mentioned.

— The rotation-transmitting shaft has a complex system of seals that prevent leakage of pressurized fluid. These seals gradually wear out, which predetermines the need for regular preventive maintenance, including replacement with new ones.

- The operation of such pumps is always accompanied by a noise effect - due to the need for air cooling of the electric drive. This also imposes its own restrictions on the choice of the installation location of the device.

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In a word, if the heating system does not require specifically high pressure and coolant flow rates, the best option would still be to purchase a wet rotor pump.

• Pumps with a "wet rotor" are arranged differently. The circuit diagram is shown in the illustration below:

The body of the power block (pos. 1) is hermetically connected to the body of the pumping chamber (pos. 2) with the help of several screws (pos. 3) due to ring gaskets. On both sides of the working chamber - "snail" there are certain fasteners for tapping into pipes - these can be threaded pipes (pos. 4) for a coupling connection or flanges.

Inside the power unit there is a stator winding (pos. 5) - this is the only compartment that does not come into contact with the liquid medium - it is hermetically separated from all the others by a stainless steel "glass" (pos. 6). Thus, the seals stand exclusively on static parts, that is, they do not wear out from friction.

Inside there is a rotor (pos. 7), on the shaft of which the pump impeller (pos. 8) is rigidly put on. The rotor rests on bearings that receive constant lubrication from the coolant. The liquid medium that fills the entire internal space of the pump is also an excellent heat remover, and the device is not in danger of overheating, and an additional engine cooling system is not required. In order to ensure complete filling of the entire volume of the pump with coolant, a special plug (pos. 9) is provided for air release.

The rotation of the pump rotor in a liquid medium, of course, entails certain energy losses, that is, a decrease in the efficiency of the device. But against the background of low electricity consumption - this factor does not seem worthy of special attention - due to the insignificance of losses.

The operation of the pump is almost silent, the device is compact and easy to install - the op simply crashes into the desired section of the pipe, without requiring any additional fasteners. True, in this case, an important condition must be observed - the rotor axis, regardless of the position of the housing, must take a horizontal position. In this position, the bearings will never be dry, and failure due to overheating does not threaten them.

Another detail is that solid suspensions should not be allowed to enter the bearings, which may well form in the circuits of the system. Therefore, immediately before the pump, it is always recommended to install a mechanical filter - "mud".

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Criteria for evaluating the circulation pump when choosing

When choosing a circulation pump for installation in an existing heating system, a number of criteria must be taken into account.

• Supply voltage. On the scale of autonomous heating systems for apartments and private houses, pumps with single-phase power supply 220 V 50 Hz are used. Low current consumption eliminates the need to lay any dedicated power lines - there are enough power outlets. The only thing that is desirable to provide is an uninterruptible power supply, which was mentioned above.
• Power consumption. Naturally, the lower it is (while maintaining other performance characteristics), the more economical the device. The best choice would be a device of energy class "A", even if it costs more. The lower the class (“B”, “C”, and so on), the greater the energy consumption.

Most modern pumps have the ability to select one of two or three operating modes, with different indicators of the generated pressure. In accordance with this, the power consumption also changes. Usually, the indicators are placed on the nameplate of the device, in the form of a plate.

Since we touched upon the issues of purely operational characteristics that affect the operation of the heating system - productivity and the pressure created, it makes sense to consider these indicators in more detail.

There are tables by which you can approximately determine the necessary parameters - one of them is located below.

Total floor space	Required thermal power (kW) at the temperature difference of the coolant in the supply and return pipes (Δt)			Pump parameters, min (excluding the hydraulic resistance of the circuits and their branching)
	Δt= 20 °C	Δt= 15 °С	Δt= 10 °С	Productivity (m³/hour)	Head (m water column)
up to 200	28,0	21,0	14,0	1,25	1,0
350	46,0	35,0	23,0	2,0	2,0
500	70,0	52,0	35,0	3,0	2,0
900	116,0	87,0	58,0	5,0	3,0
1100	140,0	105,0	70,0	7,0	3,0
Δt= 20 °С - optimal mode for heating radiators
Δt= 15 °С - optimal mode for heating convectors
Δt= 10 °С - optimal mode for "warm floor" circuits

However, it is far from always possible to rely on such tabular values, since they are usually calculated for "ideal" operating conditions, and do not take into account many factors. It will not be difficult to determine the desired values ​​\u200b\u200band yourself.

• pump performance. The main task of this device is to move a certain amount of coolant along the circuit, that is, ultimately, the necessary amount of thermal energy sufficient for the efficient operation of heat exchange devices (radiators, converters, “warm floor” circuits).

The following values ​​are required for the calculation:

W- the required thermal power (expressed in watts) of the heating system, providing a comfortable temperature in the premises under the most adverse weather conditions.

The power value of the owners should be known. If not, then it can also be calculated for each room separately, and then summed up.

How to independently calculate the required heat output of the heating system?

There is a clear and fairly accurate algorithm for such calculations. On our portal, it is implemented in a special calculator, which you will find in the article

Δ t- temperature difference in the "supply" and "return" pipes of the heating circuit at the entrance to the boiler and the exit from it. The optimal values ​​for different types of heat exchangers are shown in the table above.

WITH- heat capacity of the coolant, expressed in W × h / (kg × °С). For water, it is 1.16. If a different coolant is used, then this parameter should be indicated on its packaging. It happens. That this value is shown by the manufacturer in other units - in kJ / (kg × ° С). It is easy to translate - the correction factor is 0.28. That is, 1 kJ = 0.28 Wh.

Formula for calculating the required performance ( G) is as follows:

G=W/(∆t × C)

This formula yields a performance indicator expressed in kilograms per hour. It remains only to translate this value into a volumetric expression, taking into account the density.

We suggest using the pump performance calculator - it will quickly and accurately lead to the desired result.

Uniform distribution of heat in a house with an autonomous heating system is due to the model of the pumping device used. Due to this equipment, the forced movement of a warm medium through pipes and radiators is ensured.

To determine which heating pump connection scheme will be optimal for self-implementation, many details have to be taken into account. In this article, we will consider in detail the possible connection schemes, we will analyze in detail the connection rules.

We will also pay attention to the intricacies of choosing a place for installation, supplementing the material with thematic photos and diagrams.

A couple of decades ago, in the private sector, houses were equipped with gravity-flow heating. A wood stove or gas boiler was used as a heat source. For overall circulation devices, there was only one area of ​​\u200b\u200bapplication - district heating networks.

Today, manufacturers of heating equipment offer smaller units with the following advantages:

1. Increased the speed of movement of the thermal carrier. The heat generated by the boiler quickly enters the radiators. Due to this, the process of warming up the premises was significantly accelerated.
2. The higher the speed of movement, the higher the throughput of the pipes. This means that the same amount of heat can be delivered to the rooms with a smaller diameter pipe.
3. Water heating schemes have undergone significant changes. The highway can be laid with the slightest slope. Also, the complexity and length of the line can be anything. The basic rule is the rational choice of the heating pump based on the required power.
4. With the help of a household circulation device, it became possible to organize underfloor heating in the house, as well as an efficient closed-type heating system.
5. It became possible to hide the entire heating line of communications passing through the rooms, which is not always well combined with the design of the room. Quite common options for laying pipes behind stretch ceilings, in walls or under flooring.

The disadvantages of pumping systems include the conditionality of functioning from the supply of electricity and its consumption by the pumping apparatus during the heating season.

The leading company Grundfos, which develops equipment for heating, has released innovative models of Alpfa2 circulation pumps that can change performance based on the needs of the heating system, which saves on electricity consumption

Therefore, if the site is often deprived of power supply, it would be advisable to install a device to provide electricity in uninterrupted mode. The second drawback is not critical and can be eliminated by the power and model of the circulation pump.

Choice of insertion point of the device into the system

The installation of a circulation pump is supposed to be in the area immediately after the heat generator, not reaching the first branching line. The selected pipeline does not matter - it can be either a supply or a return line.

Where can the pump be placed?

Modern models of household heating units made of high quality materials can withstand temperatures up to a maximum of 100 ° C. However, most systems are not designed for higher heating of the coolant.

The temperature index of the coolant in the personal heating network rarely even reaches 70 °C. The boiler also does not heat water above 90 degrees.

Its performance will be equally effective both on the supply and on the return branch.

And that's why:

1. The density of water when heated to 50 ° C is 987 kg / m 3, and at 70 degrees - 977.9 kg / m 3;
2. The heating unit is capable of generating a hydrostatic pressure of 4-6 m of water column and pumping almost 1 ton of coolant per hour.

From this we can conclude: an insignificant difference of 9 kg / m 3 between the static pressure of the moving coolant and the return does not affect the quality of space heating.

Are there exceptions to the rules?

As an exception, inexpensive ones can serve - with a direct type of combustion. Their device does not provide for automation, therefore, at the moment of overheating, the coolant begins to boil.

Installation of collector wiring in a heating system using a solid fuel boiler is considered the most effective. However, this type of heating of a private house is one of the most difficult to perform.

Problems begin to arise if the electric pump installed in the supply line begins to fill with hot water with steam.

The heat carrier penetrates through the housing with the impeller and the following occurs:

1. Due to the action of gases on the impeller of the pumping device, the efficiency of the unit decreases. As a result, the coefficient of the circulation rate of the heat carrier is significantly reduced.
2. An insufficient amount of cold liquid enters the expansion tank, located near the suction pipe. The overheating of the mechanism increases and even more steam is formed.
3. A large amount of steam, when it enters the impeller, completely stops the movement of warm water along the line. Due to the increase in pressure, a trip occurs. Steam is released directly into the boiler room. An emergency is being created.
4. If the firewood is not extinguished at this moment, the valve will not be able to cope with the load and an explosion will occur.

In practice, from the initial moment of overheating to the operation of the safety valve, no more than 5 minutes pass. If you mount the circulation mechanism on the return branch, then the length of time for which steam enters the device increases to 30 minutes. This gap will be enough to eliminate the heat supply.

In inexpensive heat generators made of low quality metal, the pressure of the safety valve is 2 bar. In high-quality solid fuel boilers - this indicator is 3 Bar

From this we can conclude that it is impractical and even dangerous to install a circulation device on the supply line. Pumps for solid fuel heat generators are best mounted in the return pipeline. However, this requirement does not apply to automated systems.

Heating with a group of individual lines

If the heating system is divided into two separate lines, heating the right and left sides of the cottage or several floors, it would be more practical to install an individual pump for each of the branches.

When installing a separate device for the heating line of the second floor, it becomes possible to save money by adjusting the required mode of operation. Due to the fact that heat has the ability to rise, it will always be warmer on the second floor. This will reduce the rate of circulation of the coolant.

The tie-in of the pump is carried out in a similar way - in the area located immediately after the heat generator to the first branch in this heating circuit. Usually, when installing two units in a two-story house, the fuel consumption for servicing the upper floor will be significantly less.

Schemes for different types of systems

Initially, it is necessary to determine the tie-in zone of the circulation device. With its help, the process of active movement of the liquid is carried out - the flow passes through the boiler and is forcibly directed to the heating radiators.

For the location of the domestic pump, it is necessary to determine the most convenient area so that it can be easily serviced. At the feed, it is installed after the shut-off valves of the boiler.

In order to carry out maintenance and control of the functioning of the equipment, it is necessary to install shut-off valves. Thus, any element of the heating system can be removed without completely dismantling the line

On the return pipeline, the pump is placed after the expansion tank in front of the heat generator.

Due to the presence of various mechanical impurities in the water, for example, sand, problems may arise in the operation of the pumping mechanism. Particles contribute to the jamming of the impeller, and in the worst case, to stopping the motor. Therefore, directly in front of the unit, you will need to put a strainer-strainer.

Separately, it is worth mentioning the issue of an open-type heating system. It is capable of operating in two modes - with forced and gravity circulation of the coolant.

The second option is more suitable for areas with frequent blackouts. This is much more economical than buying an uninterruptible power supply or a generator. In this case, the unit with shut-off valves must be installed on, and a tap must be inserted into a straight line.

In stores you can find ready-made units with a bypass. In place of the flow tap, they have a check spring valve. This solution is not recommended - the valve produces a resistance force of 0.1 bar, which is listed as a large indicator for a gravity-flow type circulation system.

It is better to use a reed valve instead. However, its installation is carried out strictly horizontally.

Solid fuel pump and boiler

The pump is connected to a system with a solid fuel unit on the return line. In this case, a pumping device is connected to the boiler circuit with a bypass and a three-way mixing valve. In addition, the latter can be equipped with a servo drive and a clamp-on temperature sensor.

The solid fuel boiler connection scheme is based on two important elements that allow it to function effectively in the heating system of a private house. These include: a safety group and a mixing unit based on a three-way mixing valve

Due to the fact that the maximum performance of heating equipment is used to the full only in the cold period, it is possible to install a heat accumulator (TA). It is able to absorb excess heat, and then, on demand, give it to the heating circuit.

This battery is made in the form of a tank and lined with heat-insulating material. On one side of the device there are two branch pipes intended for its connection, and two on the other - for connection to the radiator line.

The heat accumulator has two circuits: small and large. The first receives energy from the boiler, the second - gives the coolant to the heating system as needed

In the process of passing the liquid through the boiler, which operates at maximum, the coolant in the heat accumulator warms up to 90-110 degrees over time. In a large circuit, a tie-in of another circulation device is required.

Depending on the degree of cooling of the liquid in the heating system, the required amount of heat from the storage device will enter here through the valve.

Pump installation diagram

To perform its functions, household circulation equipment, regardless of the manufacturer, must be on a pipe or shut-off and control valves.

Fastening is carried out by means of union nuts. This fixation option will allow, if necessary, to remove it, for example, for inspection or repair.

When choosing a model of a circulation pump, it is necessary to pay attention to its ability to function in different positions. Vertical placement of the device reduces its power by up to 30%

Correctly executed installation of all elements of the heating system ensures uniform heating of the entire line.

During the installation of the circulation pump, the following rules must be observed:

1. It is allowed to install the device on any section of the pipe. The pipeline can be positioned horizontally, vertically or inclined. However, the rotary axis must be in a horizontal position. Therefore, installation "head down" or, conversely, up is not possible.
2. It is worth paying attention to the location of the plastic box where the power contacts are located - they will be on top of the case. Otherwise, they may be flooded with water in an emergency. To do this, unscrew the fixing screws on the casing and turn it in the required direction.
3. Observe the direction of flow. It is indicated by an arrow on the body of the device.

With all its weight, the pump presses on the body of ball valves located nearby. This should be taken into account when choosing fittings. High-quality parts are equipped with a powerful body, which during operation will not be covered with cracks from daily loads.

Installation of additional equipment

Regardless of the type of heating circuit used, where one boiler serves as a heat producer, it will be enough to install a single pumping device.

If the system is structurally more complex, it is possible to use additional devices that provide forced circulation of the liquid.

The need for this appears in the following cases:

• when heating a house, more than one boiler unit is involved;
• if there is a buffer capacity in the strapping scheme;
• the heating system diverges into several branches, for example, maintenance of an indirect boiler, several floors, etc.;
• when using a hydraulic separator;
• when the length of the pipeline is more than 80 meters;
• when organizing the movement of water in the floor heating circuits.

To perform the correct piping of several boilers operating on different fuels, it is necessary to install backup pumps.

For scheme c, it is also necessary to install an additional circulation pump. In this case, the line consists of two circuits - heating and boiler.

A more complex heating scheme is implemented in large houses on 2-3 floors. Due to the branching of the system into several lines, pumps for pumping coolant are used from 2 or more.

They are responsible for supplying the coolant to each of the floors to various heating devices.

Regardless of the number of pumping devices, they are installed on the bypass. In the off-season, the heating system can operate without a pump, which is closed using ball valves

If it is planned to organize heated floors in the house, then it is advisable to install two circulation pumps.

In the complex, the pumping and mixing unit is responsible for preparing the coolant, i.e. keeping the temperature at 30-40 ° C.

In order for the power of the main pumping device to be enough to overcome the local hydraulic resistance of the floor contours, the length of the line should not exceed 50 m. Otherwise, the heating of the floors will become uneven, respectively, and the premises

In some cases, the installation of pumping units is not required at all. Many models of wall-mounted electric and gas generators already have built-in circulation devices.

Rules for connecting to the power supply

The circulation pump is powered by electricity. The connection is standard. It is recommended to run a separate power supply line with a surge protector.

To connect, you need to prepare 3 wires - phase, zero and ground.

You can choose any of the connection methods:

• through the device
• connection to the network along with an uninterruptible power supply;
• pump power supply from the boiler automation system;
• with thermostat control.

Many are wondering why complicate, because the connection of the pump can be done by connecting the plug to the wire. This is how the pumping device is plugged into a regular outlet.

The circuit with a differential automaton is used for the so-called wet groups. The heating system built in this way provides a high degree of safety for wiring, equipment and people.

The first option is not difficult to self-assemble. It is necessary to install a differential machine for 8 A. The wire cross section is selected based on the rating of the device.

In the standard scheme, power is supplied to the upper sockets - they are marked with odd numbers, the load - to the lower ones (even numbers). Both phase and zero will be connected to the machine, so the connectors for the latter are denoted by the letter N.

To automate the process of stopping the circulation of the heat carrier when it cools to a certain temperature, an electrical circuit for connecting a pump and a thermostat is used. The second is mounted in the supply line.

At the moment when the water temperature drops to the specified value, the device disconnects the power supply circuit.

In order for the thermostat to turn off the circulation process at the right time, it is installed on the metal section of the pipeline line. Due to the poor conduction of heat by polymers, mounting on a plastic pipe will cause incorrect operation of the device

There are no difficulties in supplying electricity through an uninterruptible power supply, for this it has special connectors. A heat generator is also connected to them when there is a need to provide electricity.

If you choose the method of connecting the pump to the boiler control panel or automation, you will need good knowledge in the power supply system or the help of a professional.

Conclusions and useful video on the topic

Rules for installing heating equipment in the video:

The video explains the features of a two-pipe heating system and demonstrates different installation schemes for devices:

Features of connecting the heat accumulator to the heating system in the video:

If you know all the connection rules, there will be no difficulties with the installation of the circulation pump, as well as when connecting it to the power supply at home.

The most difficult task is to insert a pumping device into a steel pipeline. However, using a set of lerok for creating threads on pipes, you can independently equip the pumping unit.

Do you want to supplement the information presented in the article with recommendations from personal experience? Or maybe you saw inaccuracies or errors in the reviewed material? Please write to us about it in the comments block.

into the heating system. In it, I noticed that, along with manual switching to work with a circulation pump, there is an option for tapping a circulation pump in which a person may not control its on / off. If there is power supply to the pump, then the coolant passes through the pump. If there is no power supply to the pump, then the coolant circulates naturally.

Where to embed the pump, on the coolant supply or return?

In the last article I touched on this issue, here I will repeat and supplement. Practitioners believe that there is no fundamental difference where to insert the circulation pump into the coolant supply or into the return line. Modern circulation pumps are not afraid of pressure and work great here and there.

However, in practice, more often it is necessary to repair pumps installed for direct coolant supply in systems with solid fuel heating boilers. It is in them that the system boils for a long time and the circulation pump fails.

Let's return to the topic of the article and look at two options for inserting a circulation pump.

Option 1. Non-volatile tie-in of the circulation pump

A non-volatile tie-in of the circulation pump allows you to automatically, without human intervention, switch the system to natural and forced circulation. This is achieved by setting to the shut-off bypass not of a ball valve, but ball valve.

This scheme works like this. When the pump is running, the ball of the ball valve is pressed by the pressure of the pump and blocks the natural circulation line. If the power supply to the pump is interrupted or the pump fails, the valve ball floats and the natural circulation of the coolant resumes.

Option 2. Insertion of a manually controlled circulation pump

In this scheme, the movement of the coolant is controlled manually. In order for the coolant to move forcibly (through the pump), the bypass ball valve closes and the valves near the pump open. In order for the coolant to move naturally, without the participation of the pump, the valves are closed in reverse.

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How to choose a ball valve

If we imagine the mechanics and physics of closing a pipe with a ball valve ball, then a logical question arises: how a ball valve will work if it is not installed vertically, but horizontally or at an angle.

conclusions

High-quality installation of a circulation pump in a heating system includes (mandatory):

• Checking the marking of the pump;
• Installation of a pump with a bypass line (bypass);
• According to the movement of the coolant, we put a coarse filter (preferably magnetic) in front of the pump. Without a filter, the pump vanes will quickly fail;
• The pump is surrounded by ball valves. This will allow you to repair the pump at any time, while not disrupting the operation of the heating system;
• We put either a ball valve or a cast-iron ball valve in the main coolant line. They will allow the coolant to bypass the pump in case of failure and not disturb the heating system.

The most common problem that owners of country houses have to face in the cold season is the uneven distribution of heat in the heating system. The natural circulation of hot water in the circuit is often not enough: the liquid in the boiler reaches the boiling point, and the batteries in the distant rooms remain barely warm. Modernizing an existing system is not so difficult - you just need to arrange a forced water exchange using special equipment. But where to install the circulation pump so that it works as efficiently as possible?

Correct and incorrect installation of the circulation pump

Functions of the circulation pump

Let's start with the fact that there are two ways to improve the situation with the heating of a private house - installing pipes of a larger diameter or installing a pump. The first option is used extremely rarely, since it involves a complete redesign of the system. It can only be considered when building a new house, and even then there are few who want to spend finances on an expensive network. It is much easier and cheaper to equip a new or existing system with a circulation pump.

What does the tie-in of the unit give:

• The inertia of the system is reduced, as a result of which the house warms up much faster.
• The temperature of pipes and radiators located at different distances from the boiler is equalized.
• The influence of the counter-slope is leveled, the problem of air jams will disappear.

Important! It is not necessary to design a heating system designed only for forced circulation. A prolonged power outage will cause the coolant to overheat.

Circulation pump connection diagram

Location of the pump in the circuit

Where to install the circulation pump? Formally, modern equipment works equally well on any part of the circuit - both on the supply and on the return. However, it is better to take into account certain nuances:

• High temperature reduces the life of bearings and plastic elements of the device, so it is better to embed it on the return pipe (in front of the boiler).
• The expansion tank must be mounted on a pipe section with a uniform water flow, and the pump will inevitably add turbulence. For this reason, the equipment is recommended to be placed in front of the boiler, but after the expander.

Important! Before installing a circulation pump, make sure that it is capable of handling boiling water.

• To facilitate installation, it is better to purchase a device with a detachable thread. Otherwise, you will have to select adapters.

Among other things, you will need a deep filter, a check valve, valves, a bypass, a set of wrenches and a factory installation manual for the pump.

What is a bypass for?

Where to install the circulation pump so that it does not interfere with natural water exchange? The gravitational heating system is characterized by minimal differences between the supply and return pipelines, and for optimal speed, minimal hydraulic resistance is required. Any turns and bends of the circuit, stop valves and a decrease in the pipe clearance can worsen the situation.

Important! For an autonomous heating system, only modern ball valves are suitable that fully open the clearance in working order.

You can buy a ready-made bypass in the store

Bypass - a piece of pipe installed between the direct and return wiring - serves just to reduce the negative effect of the circulation pump on the hydraulic resistance. The equipment crashes according to the following scheme:

• The pump is installed parallel to the main circuit, while the diameter of the bypass pipe must be smaller than the diameter of the main pipe.
• Between the tie-ins, a valve is mounted, which should close the main circuit. Otherwise, the equipment will distill water between tie-ins without directing it into the system.
• Protective valves are installed on both sides of the device. They allow you to cut off a non-working device and dismantle it if necessary.
• A check ball valve must be installed on the bypass - in the event of a power outage, it will transfer the system to natural circulation.

Important! If natural circulation is not provided, it is necessary to install a circulation pump with an uninterruptible power supply. These can be external batteries powered from a backup source.

Installing a pump in an old heating system

The old heating system with natural circulation sooner or later begins to "sabotage" its duties. Rust, scale and sludge appear in the pipes, which reduce their clearance and prevent hot water from moving along a given contour. Before installing the circulation pump, it is necessary to carry out resuscitation measures:

• Replace the old expansion tank with a membrane model. In this way, you prevent further corrosion and can reduce heat loss.
• A closed expansion tank must be equipped with a safety valve that will relieve emergency pressure when the system overheats.
• Thoroughly flush the entire pipeline by connecting it through hoses to the water supply. Take the time and effort - you need to wash as much rust and sludge as possible.

Professional flushing of the heating system

Important! If your heating system runs on a solid fuel boiler, it is better to install the circulation pump on the return line so that it does not overheat from too high a temperature.

To check the correct installation of the equipment and evaluate its performance, the system is filled with water. The central screw on the body of the apparatus is opened to remove air pockets. As soon as water appears, the pump can be started.

You can carry out installation work yourself if you have sufficient knowledge and are sure that you can apply the correct installation scheme. If you have any doubts, contact the experts. It is better to spend a small amount of money on calling an installer than to eliminate the consequences of amateur performance in severe frosts.

Video: installing a circulation pump

Content

In small country houses, a stove is used for heating, usually a solid fuel stove that can directly heat one or two rooms. But a multi-room cottage or a private house requires the arrangement of an autonomous heating system. Installing a circulation pump is a prerequisite for high-quality uniform heating of all rooms that need heat.

Circulation pump in the heating system

The need for a pumping unit

If the house is not connected to the central heating network, the homeowner must solve the problem of creating a heating circuit that can evenly heat all the rooms where radiators are supposed to be installed.

In a system with natural circulation of the coolant, the heated liquid moves slowly through the pipeline, and in rooms far from the boiler, radiators are much colder compared to heating devices located closer to the heat generator. The larger the house, the higher the difference - even bringing the temperature of the coolant in the boiler jacket to critically high values ​​\u200b\u200bwill not help to increase the efficiency of air heating in distant rooms.

In some cases, the entire system will help to improve the natural circulation by changing the angle of inclination and the diameter of the pipes. But this requires major transformations in the house. It is much easier and cheaper to install a circulation pump, which will make the liquid in the pipeline move much faster.

In a closed-type system with forced circulation, pumping units are installed according to the project - on the main heating circuit with radiators, on each of the water floor heating circuits.

The disadvantages of using a pump in heating systems include energy dependence. Therefore, in areas where power outages are regularly observed, it is recommended to mount an autonomous heating system with natural circulation based on a solid fuel heat generator, and mount the circulation pump as an additional element. In the event of a power outage, heating and movement of the coolant through the pipes will continue, albeit with a loss of speed.

Pump device and principle of operation

The pumping unit of the circulation type provides additional fluid pressure in a closed heating circuit. An electric motor is attached to the pump housing, inside the housing there is a motor shaft on which the impeller is installed. The rotation of the impeller creates pressure due to centrifugal force. Due to this, the pressure of the coolant in the system increases. According to the design features, two types of circulation pumps are distinguished - “dry” and “wet”.

Circulation pump device

"Dry" aggregates

In devices of this type, the pumped liquid medium does not come into contact with the rotor. Its working part is separated from the coolant by stainless steel sealing rings. When the unit is turned on, the connection is sealed with a thin film of coolant, which is formed due to the pressure difference in the heating system and outside it.

Pumps of the "dry" type are rarely used for heating systems of private houses. The unit makes a lot of noise during operation, which is why it is necessary to soundproof the boiler room. In addition, the device is sensitive to mechanical contamination of the coolant and fails if it is damaged by a suspension that has entered the water. The advantage of the "dry" mechanism is an efficiency of 80%.

"Wet" units

When the pump is operating, the liquid medium passes through the brass or bronze body of the unit, in which steel and ceramic elements are placed, for which the coolant serves as an additional lubricant.

"Wet" pumping units are characterized by simple design, low noise, long service life. They are affordable and inexpensive to maintain. The disadvantages include low efficiency - it is about 50%. But this is enough for successful functioning as part of an autonomous heating system of a private house.

The device of the "wet" circulation pump

Principles of selection of pumping equipment

Having decided on the type of pumping unit for heating, it is necessary to correctly calculate its optimal power. It makes no sense to install a circulation pump with a large margin of power - it is more expensive and noisier during operation.

The circulation pump unit performs the following tasks:

• creates a fluid pressure that can overcome the hydraulic resistance of the heating circuit nodes;
• pumps through the pipeline the volume of coolant necessary for high-quality heating of all rooms.

• pump performance (flow rate, measured in m 3 / h) - the volume of coolant that is pumped by the device in one hour;
• head (measured in meters) - an indicator that determines the hydraulic resistance overcome by the pump.

For a cottage with several floors, with complex architecture, the calculation of the power of the pumping unit must be performed by specialists. But for small houses, calculations are carried out using simple formulas and tables.

We determine the power

Standard calculation formula: Q=0.86R/TF-TR where

• Q - pump flow rate (m 3 / h);
• R - thermal power (kW);
• TF is the temperature of the heat carrier (°C) in the supply pipe;
• TR is the temperature of the heat carrier (°C) on the return line at the boiler inlet.

It is difficult to determine the thermal power on your own, so it is more convenient to use ready-made solutions:

Method 1. According to European standards, the thermal power index (R) for a small private house is 100 W / m 2, for a multi-storey building - 70 W / m 2, for buildings with good insulation - 30-50 W / m 2. These norms are suitable for Russian regions with a mild climate.

Method 2. Russian SNiP standards are calculated for a climate with frosts down to -30 ° C. The heat output indicator for one- and two-story houses of a small area is 173-177 W / m 2, for houses with a height of 3-4 floors - 97-101 W / m 2 .

Method 3. The value for the calculation is selected according to the table presented, based on the characteristics of the building:

Calculation table of thermal power for different rooms

Note! Some errors in the calculations will not affect the functioning of the heating system if you purchase a circulation pump with adjustable output.

There is another method for determining the flow rate of the coolant (pump performance). The flow rate (Q) is equated to the boiler power (P). For example, 20 liters of coolant passes through a boiler with a capacity of 20 kW per minute. And each radiator with a power of 10 kW passes 10 liters of fluid per minute. To calculate the flow rate of the coolant in each heating circuit, it is necessary to sum up the indicators of all radiators and add the indicators of the pipeline. The flow rate of the coolant in the pipeline depends on its length and diameter. The smaller the diameter, the higher the hydraulic resistance. The table compiled for the standard coolant velocity of 1.5 m / s will help to calculate the indicators of the pipeline.

Water consumption	Diameter in inches	Water consumption	Diameter in inches
5,7	1/2	53	1 1/4
15	3/4	83	1 1/2
30	1	170 320	2 2 1/2

For every 10 meters of pipeline, 0.6 m of pressure is required, which is provided by the circulation pump. For example, if the length of the heating circuit is 100 m, the pump must provide a head of 6 m.

Pump unit installation technology

Installation of the circulation pump in the heating system can be done independently.

In addition to the pumping unit itself, elements are needed for its piping:

• two ball valves;
• deep cleaning filter;
• check valve;
• a piece of pipe for the bypass (if the pumping equipment is used to install or upgrade the gravity system).

In order for the premises to warm up evenly, regardless of the location relative to the boiler, it is necessary to properly install the pumping equipment. They begin to install a circulation pump in the heating system by choosing a place for inserting into the system.

Place of installation of the circulation pump in the heating system of a private house

Selection of a place for installation

When deciding how to install a circulation pump, it is important to remember that the device must be freely accessible for regular maintenance. It is allowed to put pumping equipment on both the supply pipe and the return pipe - the materials from which modern devices are made are designed for operation at high temperatures.

It is considered advisable to install a circulation pump in the heating system on the return pipeline directly next to the boiler for the following reasons:

• A device installed on the return pipe supplies the coolant to the water jacket, displacing air pockets that may occur in the upper part of the boiler. If the pump is on the supply pipe, when air accumulates in the boiler, it is able to create a vacuum and cause the coolant to boil.
• If the boiler malfunctions, the coolant in the water jacket may overheat and boil. The circulation unit is not able to pump the steam-water mixture, so it stops. This threatens to explode the boiler if the security group does not work.

Attention! Wood and coal solid fuel boilers, unlike gas, electric and pellet boilers, do not have reliable protection against overheating. Therefore, when installing such a heating system with your own hands, the pump is installed only on the return line.

It is mandatory to use a separate pump in the underfloor heating system - the device is mounted on the manifold to which the circuit is connected.

During the reconstruction of the gravity system, the bypass with the pump unit is cut into the return pipe near the membrane expansion tank. If the place does not allow normal access to the pump, the bypass with the device is placed on the supply pipe by inserting a check valve located vertically.

In a heating system with separate circuits for different sides of the house or different floors, pumps are mounted on each circuit. The same principle is used - the device must stand before the first branch, located closer to the boiler.

strapping

Autonomous systems with forced coolant supply cannot function in the absence of electricity, so the pumping unit crashes into the pipeline itself.

If the system is gravity, a special installation of the circulation pump in the heating system is required.

The photo below shows the installation diagram corresponding to this case:

Tying the circulation pump in the heating system

A bypass cuts into the pipeline, on which shut-off ball valves, a mud filter (in front of the pump in the direction of the coolant) and the pump unit itself are mounted. Shut-off valves are also installed in the main pipeline - while the pump is running, this ball valve is closed and the system operates in forced mode. In the absence of electricity, the ball valve is opened, and the system is operated as a gravitational one.

Thanks to shut-off valves on the bypass, the pump unit is available for maintenance and replacement without draining the coolant from the circuit. The filter retains mechanical impurities - solid particles of suspension can disable the moving elements of the pump.

Installation work

Considering how to install the circulation pump correctly, pay attention to the progress of work:

1. The coolant is drained from the system, if necessary, the pipeline is cleaned.
2. A bypass cuts into the selected place, and the diameter of the pipe for the jumper must be less than the diameter of the pipeline.
3. All elements of the pump piping must be installed on the bypass - ball valves, a sump;
4. Proper pump installation requires:
   • install the housing in accordance with the designation of the direction of the coolant flow (arrows on the housing);
   • place the "wet" unit strictly horizontally - so that it works without loss of power and overheating due to incomplete immersion of the rotor;
   • position the unit so that the power supply terminals are facing upwards.
5. Sealing of joints is carried out using special gaskets, plus a sealing compound is additionally used.
6. The unit is connected to a grounded electrical outlet.
7. After completing the installation, the coolant is poured into the system and air plugs are removed, for which the central screw is opened in the cover of the pumping unit.

Permissible (top) and prohibited positions of the circulation pump with a "wet rotor"

Attention! It is required to bleed air from the pump before each turning it on. To this end, the system completely filled with coolant is turned on for 5 minutes without closing the valve on the pump, and then it is stopped so that all the air leaves the pump.

You can do without the “de-airing” procedure by installing it on the pump unit, if the design of the device allows it.

Power supply

The pump unit operates from a 220 V household network with grounding. To connect, use a three-pin plug and an appropriate socket (phase-zero-ground), or connect the wires to the unit's terminals - they are located under a plastic cover. For reliable operation, it is recommended to allocate a separate line for the pump and install a circuit breaker.

The electrical circuit for connecting the circulation pump is shown in the figure.

Connecting the circulation pump to the power supply - zero, phase, ground

Results

Pumping equipment installed in accordance with all the rules will make the heating system of a private house efficient. To increase reliability, it makes sense to take care of a backup power source - batteries for the pump.

In order for the unit to work properly, we must not forget about de-airing before starting, about regular cleaning of the mud filter from accumulated dirt.