How to properly install a heating pump. Where is it better to install the pump: supply or return? Circulation pump installation diagrams
The uniform distribution of heat in a house with an autonomous heating system is determined by the model of pumping device used. This equipment ensures the forced movement of a warm medium through pipes and radiators.
To determine which heating pump connection diagram will be optimal for independent implementation, many details must be taken into account. In this article, we will consider in detail possible connection schemes and analyze the connection rules in detail.
We will also pay attention to the subtleties of choosing a location for installation, supplementing the material with thematic photos and diagrams.
Just a couple of decades ago, in the private sector, houses were equipped with gravity-type heating. A wood stove or gas boiler was used as a heat source. There was only one area of application left for large circulation devices - centralized heating networks.
Today, manufacturers of heating equipment offer smaller units that have the following advantages:
- The speed of movement of the coolant has increased. The heat generated by the boiler quickly enters the radiators. Due to this, the process of warming up the premises was significantly accelerated.
- The higher the movement speed, the higher the pipe capacity. This means that an identical volume of heat can be delivered to rooms using a pipe with a smaller diameter.
- 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 a heating pump based on the required power.
- With the help of a household circulation device, it became possible to organize heated floors in the house, as well as an efficient closed-type heating system.
- It became possible to hide the entire heating communication line, passing through the rooms, which does not always go well with the design of the room. Options for laying pipes behind suspended ceilings, in walls or under floor coverings are quite common.
The disadvantages of pumping systems include the dependence of operation on the supply of electricity and its consumption by the pumping apparatus during the heating season.
The leading company Grundfos, engaged in the development of heating equipment, has released innovative models of Alpfa2 circulation pumps, capable of changing performance based on the needs of the heating system, which allows saving on electricity consumption
Therefore, if the area is often deprived of power supply, it would be advisable to install a device to provide uninterrupted power. The second drawback is not critical and can be eliminated by the power and model of the circulation pump.
Selecting the location for inserting the device into the system
The installation of the circulation pump is supposed to be in the area immediately after the heat generator, not reaching the first branch line. The chosen pipeline does not matter - it can be either a supply or a return line.
Where can I put the pump?
Modern models of household heating units, made of high-quality materials, can withstand temperatures of a maximum of 100 °C. However, most systems are not designed for higher heating of the coolant.
The temperature of the coolant in the personal heating network rarely even reaches 70 °C. The boiler also does not heat the water above 90 degrees
Its performance will be equally effective on both the supply and return branches.
And that's why:
- The density of water when heated to 50 °C is 987 kg/m3, and at 70 degrees – 977.9 kg/m3;
- The heating unit is capable of generating hydrostatic pressure of 4-6 m of water column and pumping almost 1 ton of coolant per hour.
From this we can conclude: the insignificant difference of 9 kg/m 3 between the statistical 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 with a direct combustion type can serve. Their device does not provide automation, so 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 and steam.
The coolant penetrates through the housing with the impeller and the following occurs:
- Due to the action of gases on the impeller of the pumping device, the efficiency of the unit decreases. As a result, the coolant circulation rate coefficient is significantly reduced.
- 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.
- A large amount of steam entering the impeller completely stops the movement of warm water along the line. Due to the increase in pressure, the trigger occurs. Steam is released directly into the boiler room. An emergency situation is being created.
- 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, no more than 5 minutes pass from the initial moment of overheating to the activation of the safety valve. If you install the circulation mechanism on the return branch, then the period of time during 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 response pressure of the safety valve corresponds to 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 installed in the return pipeline. However, this requirement does not apply to automated systems.
Heating with a group of separate 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 on the second floor, it becomes possible to save money by adjusting the required operating mode. Due to the fact that heat has the property of rising, it will always be warmer on the second floor. This will reduce the coolant circulation rate.
The pump is inserted in the same way - in the area located immediately after the heat generator before the first branch in this heating circuit. Typically, when installing two units in a two-story house, fuel consumption for servicing the upper floor will be significantly less.
Schemes for different types of systems
Initially, it is necessary to determine the insertion area of the circulation device. With its help, the process of active movement of liquid is carried out - the flow passes through the boiler and is forcibly directed to the heating radiators.
To locate a household pump, it is necessary to determine the most convenient area so that it can be easily serviced. On the supply side, it is installed after the boiler shut-off valve.
In order to carry out maintenance and control the functioning of 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 jamming of the impeller, and in the worst case, stopping the motor. Therefore, you will need to install a strainer strainer directly in front of the unit.
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 coolant circulation.
The second option is more suitable for areas with frequent power outages. This is much more economical than purchasing an uninterruptible power supply or generator. In this case, the unit with shut-off valves must be installed on, and a tap must be inserted into the direct line.
In stores you can find ready-made units with a bypass. In place of the flow tap, there is a spring-loaded non-return valve. This solution is not recommended - the valve produces a resistance force of 0.1 Bar, which is considered a large indicator for a gravity-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 the system with a solid fuel unit on the return line. In this case, the 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 an overhead temperature sensor.
The connection diagram for a solid fuel boiler is based on two important elements that allow it to function effectively in the heating system of a private home. 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 its fullest extent only during the cold period, it is possible to install a heat accumulator (TA). It is able to absorb excess heat and then, on demand, release it to the heating circuit.
This battery is made in the form of a tank and is lined with thermal insulation material. On one side of the device there are two pipes intended for connecting it, and two on the other - for connecting to the radiator line.
The heat accumulator has two circuits: small and large. The first one receives energy from the boiler, the second one supplies coolant to the heating system as needed.
As the liquid passes through the boiler, which operates at maximum, the coolant in the heat accumulator warms up over time to 90-110 degrees. In a large circuit, the insertion 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 through the valve.
Pump installation diagram
To perform its functions, household circulation equipment, regardless of the manufacturer, must be connected to a pipe or shut-off and control valves.
Fastening is done using union nuts. This fixation option will allow you to remove it if necessary, for example, for inspection or repair.
When choosing a circulation pump model, you need to pay attention to its ability to function in different positions. Vertical placement of the device reduces its power by up to 30%
Correct installation of all elements of the heating system ensures uniform heating of the entire line.
When installing the circulation pump, the following rules must be observed:
- It is allowed to install the device on any section of the pipe. The pipeline can be located horizontally, vertically or inclined. However, the rotor axis must be in a horizontal position. Therefore, installation “head down” or, conversely, up is impossible.
- It is worth paying close attention to the location of the plastic box where the power supply contacts are located - they will be on top of the body. Otherwise, they may be flooded with water in an emergency. To do this, you will need to unscrew the fastening screws on the casing and turn it in the required direction.
- Observe the direction of flow. It is indicated by an arrow on the device body.
With all its weight, the pump presses on the body of the 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 become cracked from daily stress.
Installation of additional equipment
Regardless of the type of heating circuit used, where one boiler serves as the heat producer, it will be sufficient to install a single pumping device.
If the design of the system is more complex, it is possible to use additional devices that provide forced circulation of liquid.
This becomes necessary in the following cases:
- when heating a house, more than one boiler unit is involved;
- if there is a buffer capacity in the piping scheme;
- the heating system diverges into several branches, for example, servicing an indirect boiler, several floors, etc.;
- when using a hydraulic separator;
- when the pipeline length is more than 80 meters;
- when organizing water movement in floor heating circuits.
To perform the correct piping of several boilers operating on different fuels, there is a need to install backup pumps.
For scheme c, the installation of an additional circulation pump is also required. In this case, the main line consists of two circuits - heating and boiler.
A more complex heating scheme is implemented in large houses with 2-3 floors. Due to the branching of the system into several lines, 2 or more pumps are used to pump the coolant.
They are responsible for supplying coolant to each floor 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 shut off using ball valves
If you plan to install 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. maintaining the temperature at 30-40 °C.
In order for the power of the main pumping device to be sufficient to overcome the local hydraulic resistance of the floor contours, the length of the line should not be more than 50 m. Otherwise, the heating of the floors will become uneven and, accordingly, the rooms
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 power supply
The circulation pump is powered. The connection is standard. It is recommended to install a separate power supply line with a surge protector.
To connect, you need to prepare 3 wires - phase, neutral and ground.
You can choose any of the connection methods:
- via device;
- connection to the network together with an uninterruptible power supply;
- power supply to the pump from the boiler automation system;
- with thermostat regulation.
Many people wonder why complicate things, because connecting the pump can be done by connecting a plug to a wire. This is how the pumping device is plugged into a regular outlet.
A circuit with a differential machine is used for so-called wet groups. A heating system constructed in this way ensures a high degree of safety for wiring, equipment and people.
The first option is not difficult to assemble yourself. It is necessary to install an 8 A differential circuit breaker. The wire cross-section is selected based on the device rating.
In the standard scheme, the power supply is carried out to the upper sockets - they are marked with odd numbers, the load - to the lower ones (even numbers). Both phase and neutral will be connected to the machine, so the connectors for the latter are designated by the letter N.
To automate the process of stopping the circulation of the coolant when cooling to a certain temperature, an electrical circuit is used to connect the pump and thermostat. The second is mounted in the supply line.
At the moment when the water temperature drops to the specified value, the device disconnects the electrical supply circuit.
In order for the thermostat to turn off the circulation process at the right time, it is installed on a metal section of the pipeline line. Due to poor heat conductivity of polymers, installation on a plastic pipe will result in incorrect operation of the device
There are no difficulties in supplying electricity through an uninterruptible power supply; it has special connectors for this. 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 of 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 a heat accumulator to a heating system in the video:
If you know all the connection rules, there will be no difficulties with installing the circulation pump, as well as when connecting it to the power supply at home.
The most difficult task is inserting a pumping device into a steel pipeline. However, using a set of guides for creating threads on pipes, you can independently arrange the pumping unit.
Would you like to supplement the information presented in the article with recommendations from personal experience? Or maybe you saw inaccuracies or errors in the material reviewed? Please write to us about this in the comments block.
Many small houses have gravity heating systems. They work thanks to the random circulation of water, which is caused by the change in the masses of warm and cold water entering the system.
But they are not able to heat large buildings or even houses with two floors. This requires the installation of a circulation pump in the selected heating system.
Such a device is designed to ensure that heat flows evenly to all components of the heating system.
Why is it necessary to connect a pump to the heating system?
To heat large buildings or even houses with two floors, it is necessary to install a circulation pump in the selected heating system.
Happy owners of a private home who have their own separate heating system may encounter the problem of uneven distribution of thermal energy throughout the house.
In rooms far from the boiler, the batteries may simply not warm up. This problem needs to be solved.
Most often the following options are used for this:
- Creation of a new heating system with a larger diameter pipeline.
- Inserting a pump into a heating system that is already present.
The first method, of course, is quite effective and very practical, but it costs much more than installing a pump in the heating system, and it will require much more effort. After all, you need to dismantle old pipes, and this is not an easy task.
But the second of the proposed options will be simpler, faster and cheaper to implement, as you can see for yourself.
Improving the heating system with the help of a pump will help not only stabilize the temperature throughout the house, but also get rid of pipe problems such as air pockets that form inside and prevent the coolant from circulating.
The advantages of a circulation pump are obvious, so every year more and more people connect the pump to their heating system in order to optimize the heating system of their home and get rid of the traditional problems that arise for owners of private houses.
Features of pump selection
Installation of any pump in an existing or planned heating system begins with the selection of the unit. It must be remembered that to successfully heat an ordinary house, you do not need a huge device with sky-high power.
Such a device will create unnecessary noise, it costs more and, in fact, there is no need for it. Before you start choosing a pump, you need to calculate the power level of the device that will suit you and your home.
The main indicators of power are the diameter of the existing pipeline, the level of coolant pressure and the water temperature. In order to calculate the level of coolant flow that is passed through the closed loop of the heating system, you simply need to compare it with the water flow rate for the boiler.
You need to know what the power of the boiler is, how many liters of coolant per minute can pass through its system. In addition, it is necessary to calculate how much water is required for the safe operation of each radiator and each ring of the heating system.
The power of a battery depends on how many liters per minute it needs to operate optimally.
It must be remembered that the power indicators of the circulation pump depend on the length of the pipeline. In fact, for ten meters of a heating system, about half a meter of pumping pressure is needed.
Type of pumps
To figure out how to install a heating pump, you first need to understand what exactly these devices are.
It is customary to use two types of pumps: the so-called “dry” and “wet”.
During operation, the former do not come into any contact with the coolant itself, while the latter are immersed in the water that is pumped.
“Dry” pumps are usually very noisy, so the installation of a pump for heating of this type is more suitable for large enterprises, firms, and production workshops.
But units that operate in water are typical for heating country houses and private buildings.
They are usually made in special bronze or brass cases with stainless steel parts so that the system is not damaged by water.
If you need to optimize the heating of your personal home, then you should figure out how to properly install a pump for this type of heating.
Initial installation stage
To make the installation of the pump easier and faster, try to find a device in stores with already selected detachable threads.
This will save you from having to rush around looking for fasteners and connections yourself. Also stock up on all the necessary wrenches to install the above fasteners.
After all the preparatory steps have been completed, you need to study the instructions for the pump and its mounting diagram. If you are not confident in your abilities, then it is better to involve a professional in this process.
Selecting a place to install the pump
A correctly selected installation location will allow you to gain convenient access for maintenance in the future. Click to enlarge.
It is very important that the heating pump connection diagram implies the fact that the system will need to be serviced periodically, so it would be nice to have an approach to it.
If some parts of “wet” pumps of older models could be damaged from constant contact with water, today such systems are produced in such designs that they are absolutely not afraid of moisture, as well as high or low temperatures.
This allows installation on both the supply and return pipelines.
In order to increase the degree of pressure in the suction section, install the unit near the connection point of the expansion tank in the area of the descending heating pipeline.
You must be sure that the pump can withstand strong pressure of hot water, otherwise problems will arise.
Installation Rules
If you have already studied the theoretical part of the question of how to install a heating pump, then it’s time to start practicing. To do this, you should adhere to several basic installation rules. Here are some of them:
On both sides of the pumping equipment itself, you need to attach special ball valves, which you will need during system maintenance or dismantling the pump itself.
The principle of connecting a house heating pump. Click to enlarge.
The system must be equipped with a filter. This is done in order to protect the device from small particles that could damage the installation and its components.
Alas, the water in heating systems is still far from ideal, so pumps require additional protection.
A valve must be installed on top of the heating bypass. It can be manual or automatic - it doesn't matter that much.
It is necessary in order to release air pockets that will begin to form in the pipes after some time.
The terminals of such a pump should be directed straight up.
And the unit itself, if it is a “wet” model, must be installed horizontally, otherwise only part of it will be present in the water, that is, the working surface may be damaged and the entire installation of the pump in the heating system will be pointless.
Each fastening and connection must be treated with a hermetic protective agent. This will increase the productive potential of the entire structure. Also make sure that the pump and fastenings are located in the heating chain naturally and consistently.
Pump installation principle
First, you need to drain the heating fluid and clean the system if this has not been done for a long time. Then install the pump in a specially designated place, according to the plan. After the system is secured, the pipes are filled with water.
Fragment of connecting the pump to the heating system. Click to enlarge.
You should carefully check for any malfunctions or errors in operation. If there are any, they are eliminated at this stage. After this, excess air is removed from the pipes using a central screw.
The pump should be connected only after the system is started, the pipes are filled with water and there is no air left in them. An automatic pump model can automate the operation of the pump and protect it from improper operation.
By the way, it is necessary to release the air before each start of the pumping unit. This de-airing of the pipes is carried out manually thanks to special valves installed on both sides of the heat pump.
Only by adhering to all the rules and taking into account all the nuances of how to connect a heating pump, can you independently install such a pump on your heating system.
Remember that this issue cannot be treated negligently, because the warmth and comfort of your home, and therefore the well-being and health of the whole family, will depend on your work. If you are not confident in your abilities, then it is better to invite a specialist for such a mission who will do the work quickly and efficiently.
A circulation pump is a small device built into a heating or water supply system. It is designed to force the coolant to disperse throughout the entire heating system. Provides uniform circulation of hot liquid, due to which the room is heated in any room, regardless of where the device is installed. The heating system pump is also designed to save heating costs.
Depending on the contact with water, pumps with a “dry” and “wet” type rotor are distinguished.
Which circulation pump should I use for heating?
A “wet” pump rotor is suitable for small private houses, and a “dry” pump rotor is suitable for large premises and multi-storey buildings. What is their difference? The first type is the most economical and silent, but is inferior in power, which limits the area of use, making it ideal for a residential building.
Advantages of circulation pumps with a “wet” type rotor:
— absence of noise;
— durability;
— ease of installation;
— saving electricity;
- small size and weight.
Advantages of pumps with a dry rotor:
- high efficiency, which provides uniform heating of large areas.
For heating private houses in the heating system, in 50% of cases pumps marked 25*4 or 25*40 are used. The first number (25) indicates the diameter of the pump connection. The second number (4 or 40) indicates the pressure of the circulation pump.
note
Some manufacturers Wilo, Oasis indicate pressure in meters, other manufacturers Grundfos, Unipump indicate pressure in decimeters.
Advantages of using heating circulation pumps
- Allows heat to be distributed evenly in all rooms.
- Fast system warm-up.
- Saving electricity and gas, which is achieved by reducing the cost of starting heating and rapid cooling of the coolant. The system is designed in such a way that the required amount of liquid is first heated, while spending a relatively small amount of energy. The benefits are huge compared to the cost of electricity to run the equipment.
- Durability of use if a properly selected pump is installed specifically for a given room.
- A universal approach for all heating systems.
In what case is it necessary to install a heating circulation pump if you have a system with natural water circulation.
— Naturally, the question arises if the water in the boiler is already boiling, but the room still does not heat up to the required temperature.
— If the slope of the heating pipes does not meet the slope standards: 5 mm per 1 linear meter. Instead of tearing down walls and installing pipes with the required slope, you can use a circulation pump; it will be more profitable, more reliable, and without headaches.
- heating pipes are in one direction and one pipe passes through the system.
- great savings benefits.
The heating system pump has these wonderful properties.
Read also:How much does it cost to install a heating system pump?
All this is not that expensive, and even more so, the purchase of a pump more than pays for itself after just a few months of use, about a couple of months of the heating season. And then there’s pure savings. It is comparable to the unregulated costs of gas and electricity. A circulation pump for heating a private house can cost from 1,500 rubles. up to 20,000 rub. Installing a circulation pump for heating can cost from 500 rubles. and higher.
Why do you need to install a heating pump?
Firstly, this will allow the batteries to warm up immediately after being connected to the power grid, in contrast to natural circulation, where heating of the heating system takes quite a long time.
Secondly, even if the pipes are laid with a negative slope, the circulation of water with uniform heat distribution is inevitable, due to which the temperature of the heating radiators will be equalized.
Thirdly, effective removal of air jams. Due to the accelerated circulation of the coolant, all air is removed from the heating system in a matter of minutes. But this is often accompanied by the sound of water running through the pipes, which can be annoying.
Fourthly, some heating system configurations will not be able to operate without a circulation pump due to high resistance in the pipelines. This is a system of warm walls, a system of warm floors, combined heating systems with heating collectors.
Read also:Selecting the right unit
Installing a pump with a high efficiency factor can lead to an increase in the amount of energy consumed, excessive noise, and wear of the device parts. At the same time, “wet” type pumps are not able to cope with the task of heating large areas due to the low power of the equipment. Modern heating circulation pumps have both manual and automatic modes for controlling the speed of rotation of the motor shaft.
High power factor is achieved at maximum shaft speed. Equip circulation pumps with thermal valves, this will allow you to regulate the heat in the room. When the temperature rises, the valve closes. Which leads to an increase in hydraulic resistance and, as a result, pressure increases. Noise appears, which can be eliminated by moving the equipment to low speeds. But there are pumps with built-in electronics that are able to regulate pressure depending on the amount of water.
How to install a heating pump?
When purchasing, you should pay attention to the presence of different threads included with the pumping equipment. If not included, you will have to choose them yourself. Cleaning filters and a check valve in accordance with the thread diameters will also be needed. In this case, you can do without adapters. For work, as a rule, you need wrenches of sizes 22-36 or adjustable wrenches, shut-off valves and a bypass - a small piece of pipe. And, in accordance with the rules that are included in the box of the purchased device, choose a place for installation.
The video shows what keys we use.
Selecting a pump insertion location
Previously, it was necessary to install equipment only in the return line. It was believed that such a system prolongs the life of the stuffing box system, rotors, and bearings. And now, the position of the pump in space does not play a special role: it can be installed both on the supply pipeline and in the return line. This is explained by the fact that modern heating system pumps do not suffer from contact with hot water. It is best to install the pump next to the heating collector.
Installation of a circulation pump in a heating system
Before installation, you must carefully read the instructions supplied with the equipment, which will allow you to understand the basic rules. The most important detail during installation is the correct position. Namely, the heating system pump must be positioned horizontally to avoid air pockets, which will leave the parts without lubrication and lead to overheating of the motor. And, accordingly, this can lead to further damage to the circulation pump. An arrow is placed on the outer part of the equipment indicating in which direction the coolant should move.
Video about the heating circulation pump in the Viessmann Vitopend 100 boiler.
A filter is installed in front of the pump to trap contaminants. If they get inside the circulation pump, parts may be damaged. Use a regular dirt filter. The filters are marked with an arrow, which indicates the direction of coolant flow in the heating circuit. Do not ignore the direction of the arrow, otherwise you will have to clean, or change if broken, the sump and pump.
Electrical connection
Some pumps can continue to operate after a power outage from the backup source, which usually lasts for a couple of hours. In connection with this purpose, it is recommended to install an uninterruptible power supply that allows the circulation to continue operating even in the absence of electricity. Usually during this time, electricians set up the electrical system. The continued uninterrupted operation of the pump in the system directly depends on external batteries connected to a backup power source.
Rules for operating the circulation pump:
The heating pump must not operate without water in the heating system.
Operating equipment with zero coolant supply is not permissible.
The range of allowable expenses must be observed. The fluid supply should not be too low or high.
If the pump is turned off for a long period of time, it is necessary to turn it on once a month for preventive purposes, at least for 1-15 minutes, to avoid oxidation of parts.
In order to avoid precipitation of hardness salts, use a water treatment system when filling the heating system. Or fill the heating system with a special coolant.
Before starting work, you must make sure that there is no vibration or noise from the heating system pump.
Check that the equipment motor does not heat up excessively.
Check for water leaks in the areas where the pump is installed.
Malfunctions of the heating circulation pump:
If sounds are heard when the heating pump is operating, but the shaft does not rotate. In this case, the root cause is possible oxidation of parts. In this case, you must turn off the device from the power supply. Drain the water by loosening the central screw of the pump. Unscrew the pump housing itself, remove the motor and impeller. If the pump has low efficiency, you can unlock the shaft by unscrewing it manually.
Properly organized water heating systems are self-sufficient in terms of circulation. The movement of water occurs naturally: when heated, it rises to the top, carrying the cold “return” with it.
If the pipes were not laid by a professional, stagnation will form in the system. It will take a long time for all heating radiators to warm up, and there is a danger of water boiling in the heat exchanger.
When starting the system after inactivity, especially at low temperatures, the heating of the room slows down, and there is a desire to speed up natural circulation.
Another disadvantage of natural circulation systems– airing of the system. The resulting air lock blocks the heat transfer of the medium, and you face the same problems. A small section of the pipe heats up, and there is a risk of the boiler overheating.
The issue is solved by installing a pump in the heating system.
This is a compact electrical device for artificial circulation of water in the system. It does not have to be simply placed in a pipeline break; the most typical installation scheme is bypass. That is, under normal conditions, when the heating system is functioning normally, the coolant circulates due to thermal convection.
When it is necessary to provide forced movement, the section of the pipeline parallel to the pump is closed, and circulation is provided by the turbine.
Installing a circulation pump– the procedure is simple, but there are rules and nuances to the operation of this device (as with the installation of any household appliances). If the turbine is installed incorrectly, you will at least get the opposite effect, and possibly make the operation of the heating system unsafe.
Correct installation of the circulation pump in the heating system
Before purchasing a pump, you need to understand which model is suitable for your system. 
Operating principle and types of circulation pumps
Everything is clear about the operating principle– the electric motor drives the turbine impeller, which creates a pressure difference between the inlet and outlet pipes of the pump. In accordance with the laws of physics, forced circulation of liquid occurs.
Piston and other specific water pumping systems are not used in everyday life, due to their bulkiness and incomparable performance.
How to properly install a Grunfos circulation pump - video.
By design, circulation pumps are divided into two types:
With wet rotor
The moving part (the electric motor rotor connected to the turbine impeller) is constantly in the water. The electrical part: stator, contact groups, brushes are separated from the rotor by a sealed glass. So everything is in order with safety and protection from electric shock.
Due to constant washing with running water, the rotor is cooled and its bearings are lubricated with coolant. This increases the service life of the device. In addition, this design ensures quiet operation. 
There are also disadvantages. Firstly, low efficiency, no more than 50%. Secondly, low productivity. A powerful impeller (and therefore a large rotor) is difficult to seal, so “wet” pumps are used on small systems with short pipe lengths. Compact dimensions allow the device to be installed neatly and discreetly.
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Private houses with an autonomous heating system with natural circulation have one common problem. The fact that the coolant circulates unevenly through the system leads to the fact that the heating devices warm up unevenly. Installation will help you cope with such nuances circulation pump.
In this article we will tell you how to connect circulation pump into the heating system.
Circulation pump in the heating system
Installation of a circulation pump in a heating system
Correct installation of the circulation pump in the heating system involves its installation through a bypass pipe - bypass. In this case, when the electrical power is turned off, the system will switch to natural circulation without difficulty. In order to start water directly, it is enough to close the valves on the bypass.
Installing a circulation pump on the bypass
Many users constantly wonder: where is the circulation pump installed in the heating system?
It is mounted on the return pipe between the outer radiator and the heating boiler. This is due to the fact that the pump does not push water, but sucks it in.
Under the influence of hot coolant in the supply pipe, its elements break down very quickly. In the middle of the pump and boiler are mounted only pressure gauge, thermometer and pressure relief valve. A filter is installed.
A large amount of various debris accumulates in any heating system: scale, silt, etc. If you neglect to install the filter, the pump impeller will very quickly become clogged, and as a result, the equipment will fail.
It is very important to place it correctly circulation pump for heating. That is why, when performing this procedure, you must use the following recommendations:
- If the connection is made into an already functioning network, then before making it, it is necessary to drain all the water from the system. The pipeline must be thoroughly flushed.
- Once the installation is complete, the system must be refilled with water.
- All connections must be lubricated.
- The last step is to open the central screw on the pump housing and release excess air from it.
This is how the circulation pump is connected to the heating system.
Where should the pump be mounted - supply or return?
Users are always tormented by the question: is it possible to put the circulation pump on supply? Despite the large amount of different information on the Internet, it is difficult to understand where to correctly install the heating pump so that there is forced circulation of water in the house.
Information regarding this issue is very contradictory. Many people say that the device should only be installed on the return pipeline, arguing that:
- the temperature of the coolant in the supply is much higher than in the return, and therefore the pump will not operate for long;
- The density of hot water in the supply line is lower, so it is difficult to pump;
- The static pressure in the return line is higher, making the pump easier to operate.
Sometimes a person happens to get into a boiler room, which provides central heating for apartments, and sees that the devices used there are embedded in the return line. Based on this, he concludes that this decision is correct, without taking into account the fact that in other boiler houses the pumps can also be installed on the supply pipe.
Experts respond to the statements described as follows:
- Household circulation pumps designed to operate at a maximum coolant temperature of 110°C. In heating systems in a house, the coolant rarely heats up above 70°C, and the boiler heats water to no more than 90°C.
- The density of water at 50°C is 988 kg/m³, and at 70°C - 977.8 kg/m³. For a device that develops a pressure of 4-6 m of water column and has the ability to pump about a ton of coolant per hour, a difference in the density of the transported medium of 10 kg/m³ will not play any role.
- In practice, the difference in static pressure of the coolant in the supply and return lines also does not have any significant effect.
The conclusion is simple: circulation pumps for heating can be embedded in both the return and supply pipelines of the heating system of a private house. This factor will not in any way affect the performance of the device or the efficiency of heat supply to the building.
Position of the circulation pump during installation
As an exception, we can highlight cheap solid fuel direct combustion boilers, which are not equipped with automation. If the coolant overheats, it will simply begin to boil, because... burning wood cannot be extinguished at once. If the circulation pump is on supply, then the emerging steam, mixed with water, will begin to flow into the housing with the impeller. The process will then look like this:
- The impeller of the pumping device is unsuitable for moving gases. That is why the performance of the unit decreases sharply, and the coolant will move at a lower speed.
- Less cooling water enters the boiler tank, causing overheating to increase and the amount of steam to increase even more.
- An increase in steam velocity and its entry into the impeller leads to a complete stop of the coolant movement in the system. This becomes the cause of an emergency and, as a result of an increase in pressure, the safety valve is activated, which releases steam directly into the boiler room.
- If no measures are taken to extinguish the firewood, the valve simply cannot cope with the pressure release and an explosion will occur with the destruction of the boiler shell.
In cheap heat generators, which are made of thin metal, the response threshold of the safety valve is 2 Bar. In higher quality TT boilers, this threshold is set at 3 Bar.
As practice shows, no more than 5 minutes pass from the start of the overheating process to the moment the valve operates. If you install the circulation pump on the return line, then steam will not get into it and the time period for an accident will increase to 20 minutes. In other words, installing a pump on the return pipe will not prevent an explosion, but it will provide a delay and you will have more time to solve the problem.
Pumps for heating boilers that operate on wood and coal are best installed on the return pipeline. For well-automated pellet units, the installation location is not of fundamental importance.
Connecting the circulation pump to the electrical network
If you used the installation method that we described above, then the circulation pump shaft will be in a horizontal position. In this case, air will not collect in it, which interferes with the lubrication of the bearings.
Among other things, when installing the unit, you must ensure that the terminal box is placed on top. It is necessary to connect the circulation pump to electricity in strict compliance with safety rules.
The power cable must have a plug or switch. The minimum distance between the contact axes is 3 mm. Cable cross-section - no less than 0.75 mm. Of course, the pump must be connected to a grounded outlet.
Number of pumps
Most often, one circulation pump is installed in the heating system of a private house. The power of the units produced today is quite enough to ensure the optimal flow rate of the coolant.
Two pumps are installed in the system in cases where the total length of the pipes is above 80 m.
Operating rules
Today, reliable pumps are produced that are characterized by a long service life. However, of course, like any other unit, the circulation pump can fail. A number of reasons may contribute to this:
- too strong/weak water supply;
- the device works when there is no coolant in the system;
- with prolonged downtime;
- when water heating greatly exceeds the norm (over 65°C).
To summarize all of the above, it is worth noting that the circulation pump is an integral part of the home heating system. With such a device, you will be protected from all kinds of errors, which can subsequently lead to minor and major troubles. You can install the circulation pump either with the help of specialists or yourself. The main thing is to strictly follow the instructions.
