How should the heating pump be positioned? How to properly install a heating pump in a private home

Circulation pump serves for forced flow of liquid through the piping.

In some cases, it also regulates the temperature. Most heating systems require the installation of circulation pumps.

Where to place the device on the heating system

It doesn’t matter which pipeline, since the device keeps the liquid hot. The same goes for hydraulics.

Carry out installation in the area near the boiler, up to the system branches. Usually they choose the return line, since in such a case the risks are minimal.

If the heating is divided on two circuits(left and right or by floor), it is better to install a pump on each. This will expand the capabilities and allow you to control a separate area of the building, which leads to resource savings.

How to properly install a pump with your own hands in a private home

One of the most important points is the direction of the rotor. If the installation is vertical, the system will almost certainly have to be rebuilt. They also take into account the flow of liquid through the pipes. There is an arrow on the device for this.

The installation principle does not matter. Study the instructions for the possibility of use in certain schemes. When choosing, take into account the power drop when installing the pump not horizontally.

Correct installation diagram

Installing the pump on bypass is often used. It allows the system to operate during a power outage. This also applies to problems with the circulator, allowing parts to be replaced without draining the water.

Photo 1. Diagram of the heating system. The number nine indicates the installation location of the circulation pump.

For installation you will need:

pump;
union nuts or flange connections (included in the kit);
filter;
shut-off valves;
bypass and valve for it.

Installation will require some space. Depending on the characteristics of the building, Project development may be required.

When creating a piping with forced water circulation It is recommended to install a special section of pipe designed for the pump. They are not common, but they make the job much easier. For the same reason, you should look for an assembled device. Otherwise, you will have to invite a specialist or do the process yourself. The assembly principle depends on the fasteners and material. The latter divides devices into two types: metal, requiring complex welding, and plastic.

Installation rarely takes more than an hour. This does not apply to steel pipes, which require complex connections. When installing, do not make any mistakes with length calculations. The work is as follows:

Preparation: selection of components and their purchase.
Tool selection: You will need keys, sealant, and possibly a welding machine.
First, three units are packed onto the tow: two for the pump and one for the tap. The first ones are distinguished by the presence of a filter. The latter is placed in the lower part, combining the pipe and the squeegee. It is applied to mark the installation location. And they also think through the junction points.
Then assemble the loop without fully tightening the nuts. At this stage, measurements are taken to determine the characteristics of the unit.
The cut parts of the pipeline are placed along a common axis on arbitrary stops. The loop is tightened, then the structure is welded. Before the next step, it is recommended to remove the pump to avoid damage.
They fasten the bottom by joining the squeegee. Having packed the latter, the pump is returned to its place. The rotor is aligned along the horizontal axis. The nuts are tightened, fixing the position of the structure. The joints are coated with sealant and proceed to the electrical part of the process, if required.

After completing the installation, you cannot immediately check it. First, the piping is filled with coolant. To prevent air from collecting in the loop at this time, open the tap. This step is optional if there is a gas outlet. When water flows from the hole, it is blocked. Having completely filled the pipes, repeat the procedure. Then they re-tighten everything, lubricate it with sealant and start using it.

The need for water filtration

A mud trap is often placed in front of the pump, the purpose of which is not to miss solid particles accumulated in the coolant. Enough to use standard coarse cleaning device, since the pipes have a small diameter.

Photo 2. Installation diagram of the pump in the heating system. The arrow indicates the place where the dirt filter is located.

The collection barrel is placed in the downward direction, which will prevent possible malfunctions.

Attention! The filter indicates direction of water flow. If you do not follow it, you will have to change the part more often.

Location of the pump in the heating circuit with the boiler

Depends on the project. Development should be entrusted to specialists to prevent possible malfunctions. It is usually placed at the bottom of the pipeline, near the boiler. For stable operation, follow the only rule: install the device before or after all branches.

Bypass purpose

The device is a shut-off valve that serves to increase hydraulic resistance. This allows the system to operate in the absence of electrical power. An open valve has the same throughput as a pipeline, so the efficiency does not decrease.

Photo 3. Bypass on which the pumping device is installed. There are several valves on the structure.

Electrical connection principle

Circulation pumps operate on mains power 220 volt. Use a regular connection, but a dedicated line is recommended. Will need 3 wires, plug and socket for three contacts. Power can also be supplied directly through the terminals. The latter are placed under the cover to the corresponding letters, and the wires are separated by color. N - zero, completely or partially blue. Grounding has a special symbol, green, sometimes in combination with yellow. L - phase, almost any color (except those mentioned above).

Having created the connection, the installation box is closed and tightened with a screw.. Depending on the manufacturer, sealant treatment is sometimes required. The cable must be sufficient to reach the power connectors.

The operation of the entire system depends on the condition of the pump, so it is recommended to provide a backup power supply. Usually the stabilizer is placed on batteries. Even automatic heating will consume no more than 300 W, so it’s enough to purchase the device at 400-450 W. Also consider the battery capacity.

For owners of country houses with individual heating systems, the issue related to the uniform distribution of heat between all rooms is particularly relevant. For this purpose, circulation pumping units are used. And the question immediately arises: how to install a heating circulation pump so that it ensures uninterrupted, highly efficient, reliable operation? In this article we will look at this issue in detail.

Reasons for installing a circulation pump

A standard problem for owners of private houses is the uneven distribution of heat throughout the heating system. If in distant rooms the radiators are lukewarm, but the boiler boils, then you have to look for methods to improve the efficiency of the entire heating system.

To distribute thermal energy throughout the house, the following solutions are most often used:

increasing the diameter of the heating system pipes;
installing a pump in a heating system that is already present.

The first method is effective and practical, but it requires significant financial and physical costs, since you will have to dismantle all the old pipes and replace them with new ones. Installing a circulation pump in the heating system will not only ensure the same temperature throughout the house, but will also prevent the occurrence of air locks, which are the cause of poor coolant circulation. In addition, the cost of installing a small pump is much lower than replacing the pipes of the entire heating system, and much less physical effort will also be required.

Design and principle of operation of the circulation pump

Circulation pumps are designed for forced circulation of warm water in closed heating systems. The pump consists of a stainless steel body and a steel rotor or motor screwed to it; an impeller is attached to the motor shaft, which contributes to the release of the coolant. The operation of the pump is driven by an electric motor. A pump installed in a heating system draws water from one side and throws it into the pipeline due to the centrifugal force that occurs when the impeller rotates. The pressure created by the pump must easily cope with the hydraulic resistance of the pipeline, radiator and other elements of the system.

Types of circulation pumps

Typically, heating pumps are divided into two types:

"wet";
"dry".

In “dry pump” designs, the rotor does not interact with the coolant; its working area is separated from the electric motor by special stainless steel sealing rings. When started, these rings begin to rotate one towards the other and a thin film of water located between the rings seals the connection due to different pressure levels in the heating system and the external environment. The efficiency of a circulation pump with a dry rotor becomes 80%. In addition, it is quite noisy compared to a “wet” pump, so it should be installed in a separate, well-soundproofed room.

In turn, “dry” pumps are divided into three types: vertical, horizontal and block. For horizontal “dry” circulation pumps, the suction pipe is located on the front of the shaft, and the discharge pipe is located on the housing. The electric motor is mounted horizontally. For vertical pumps, the pipes are located on the same axis, and the electric motor is located vertically. Warm water enters the block pump along the axis and is discharged radially. When operating a “dry” pump, the dustiness of the room should be monitored, as it can cause turbulence of dust and other small solid particles, which can damage the surface of the seal rings, and as a result, the tightness of the pump. It is worth remembering that a “dry” pump requires the presence of liquid as a lubricant, since its absence significantly increases the risk of destruction of the mechanical seal.

“Wet” circulation pumps differ from “dry” ones in that the rotor and impeller are immersed in a coolant, which simultaneously acts as a lubricant and coolant. The rotor and stator are separated by a special “glass” made of stainless steel, which ensures the tightness of the part of the electric motor that is energized. For a heating system, the body of a “wet” pump should preferably be bronze or brass, and the rotor should be ceramic. Compared to “dry” pumps, wet ones are less demanding in maintenance and repair, and in addition, they are much less noisy. However, there is also a minus: the efficiency of a “wet” pump is about 50%. This is due to the fact that it is almost impossible to seal the sleeve that separates the coolant and the stator. “Wet” circulation pumps are mainly used in domestic heating, since such performance is quite sufficient for short-length heating systems.

How to choose a heating circulation pump

The first thing you should pay attention to when choosing a circulation pump is its power. It is worth remembering that for high-quality heating it is not necessary to choose a large pump with too high power. It will only create unnecessary noise, cost much more, and there is no need for it as such.

To choose a heating device, you should make an accurate calculation of the power of the circulation pump that is optimal for your home. To do this, you need to know the following parameters: pipe diameter, water temperature, coolant pressure level, throughput and boiler performance.

It is important to know how many liters of water can pass per minute through the heating system (boiler power). In addition, it is necessary to calculate the amount of water required for the normal operation of the radiator and heating system rings.

The power of the circulation pump also directly depends on the length of the pipeline. As a rule, approximately 0.5 m of pumping head is required per 10 m of pipeline.

To calculate the coolant consumption, you simply need to equate it to the boiler power parameters. For example, if the boiler power is 25 kW, then the coolant flow is 25 l/min. Batteries with a power of 15 kW require 15 l/min of water. It is also worth remembering that the narrower the pipeline, the greater the resistance that will arise along the path of movement of the coolant.

Calculation of circulation pump flow for heating

Any circulation pump has a number of indicators, which determine its performance. The main ones are pressure and flow. These parameters are reflected in the technical data sheet.

The flow rate of the heating circulation pump is calculated using the formula:

where N is the boiler power; t1, t2 is the temperature leaving the heat source (in most cases - 90-95 degrees) and in the return pipeline (usually -60-70 degrees), respectively.

The pressure of the heating pump is calculated in the same way; according to European standards, 100 W of power is required for 1 sq.m. of private house area.

Circulation pump installation diagrams

There are two typical installation schemes for a circulation pump: single-pipe, double-pipe.

The first scheme is characterized by a constant coolant flow rate and a small temperature difference, while the second, on the contrary, is characterized by a variable flow rate and a high temperature difference.

The following figures show connection diagrams for the heating circulation pump, where: 1 - boiler, 2 - automatic air vent, 3 - thermostatic valve, 4 - radiator, 5 - balancing valve, 6 - expansion tank, 7 - valve, 8 - filter, 9- circulation pump, 10-pressure gauge, 11-safety valve.

Installing a circulation pump - stages and important installation nuances

Before installing the circulation pump, carefully study the instructions and its connection diagram. It is important to take into account the fact that the heating system will need to be serviced from time to time, so it must be taken care of.

First, you should drain all the heating fluid from the system, then, if necessary, clean the pipeline. Installation of the pump and the functional chain of fittings is carried out according to the connection diagram. Upon completion of installation, the heating system is filled with water, then excess air is removed from the pump by opening the central screw. It is worth paying attention that the air should be removed before each time the circulation pump is turned on.

After the heating circulation pump has been purchased, we begin to determine its installation location. It is recommended to install the circulation pump on the return line, in front of the boiler. The thing is that air can collect at the top of the boiler over time, and if the pump is installed on the supply, it will seem to pull it out of the boiler, as a result of which a vacuum can be created, which will lead to boiling of this part of the boiler. If the pump is placed in front of the boiler, the coolant will be pushed into it, as a result of which no air space will be created and the boiler will be completely filled. In addition, with this installation, the circulation pump will operate at lower temperatures, which will increase its service life.

At the selected pump installation site, a so-called bypass (bypass) is performed. It is necessary so that in the event of a pump breakdown or a power outage, the entire heating system does not stop working, and the coolant passes through the main pipeline thanks to open taps. It should be remembered that the diameter of the bypass pipe must be less than the diameter of the main pipeline. After the bypass is ready, proceed to installing the circulation pump.

It is important to remember that the shaft of the circulation pump must be installed horizontally, otherwise only part of it will be in the water, that is, the pump will lose about 30% of its performance, and in the worst case scenario, the working area may malfunction.

In addition, the installation also provides for an upper location of the terminal box.

Install ball valves on both sides of the pumping equipment. You will need them in the future for maintenance and dismantling of pumping equipment.

The system must necessarily include a filter, which is designed to protect the mechanism from small mechanical particles that can cause significant damage to the pump.

A manual or automatic valve should be installed on top of the bypass pipeline line, which is necessary to release air pockets that arise after a certain period.

To prevent arbitrary water flow in the heating system, it is necessary to secure shut-off valves in the pump inlet-outlet area.

When attaching the motor shaft, it is necessary to ensure that the box rotates along the axis with minimal effort. For an open heating system, it is also necessary to provide an expansion tank.

The connecting nodes should be treated with sealant, which will increase the performance of the entire heating system

To make the pump installation process easier and to avoid the need to search for connections and fasteners yourself, find in stores a special device with already selected detachable threads.

The number of circulation pumps required depends on the length of the pipeline. For example, if the length of the pipe is about 80 m, then installing one pump will be sufficient, but if the length exceeds this figure, then it is necessary to use two or more heating circulation pumps.

The cost of installing a heating circulation pump fully depends on the model of the equipment itself, the complexity of the bypass pipes and, of course, the number of pipeline circuits.

Causes of failure of heating circulation pumps

The most common causes of failure of heating circulation pumps:

incorrect pump installation

The motor shaft must be positioned strictly horizontally, otherwise air may accumulate in the pump, which will damage the device.

Incorrect terminal module position or cable routing
ignoring the pump bleeder procedure
Poor quality cleaning of the system from solid particles

It is worth remembering that all circulation pump malfunctions require specific skills and knowledge, so it is better to entrust the repair of heating equipment to professionals.

Owners of country houses often face the question of uniform distribution of heat throughout the house.

This thermal effect can be achieved in two ways:

re-equip the heating system by replacing large-diameter pipes;
perform installation.

If we consider these two methods from the point of view of economic benefits, then the first option will be more expensive and very expensive. Installing a circulating pump will prove to be an effective and relatively inexpensive means of heating your home evenly.

Let's talk in more detail about what this type of pump is and how to install it.

Purpose

This type of units is intended for forced circulation of coolant in a closed heating system.

The pressure created by the circulation pump must effectively cope with the hydraulic load of all elements of the heating system.

Therefore, in order to ensure the necessary pressure for coolant circulation, you need to choose the right circulation pump.

Calculation principle

To ensure maximum comfort in the house, you need to correctly calculate the required amount of thermal energy.

Installation of a heat pump for heating a private house:

This calculation is made based on the following points:

weather conditions in the region;
thermal conductivity coefficient of building materials from which the house is built;
installation of floor structures and ceilings of the home;
thermal conductivity properties of windows;
placement of the building relative to the cardinal directions, etc.

The result of the calculations should be the volume of coolant supplied to the heating system, which is measured in cubic meters per hour. This indicator will become fundamental when choosing.

Assembly diagram and details

The connection of the circulation pump to the heating system must be done using a bypass or bypass. A bypass is a pipeline parallel to the main one into which the circulation unit fits.

The bypass is carried out so that in the event of a pump malfunction or power outage, the heating system can operate in autonomous mode.

Important point: The size of the bypass pipes should be smaller than the diameter of the main pipeline.

The outline consists of the following elements:

Two shut-off valves, which are located on both sides of the pump (if the device breaks down, you can close the locks and dismantle the pump to troubleshoot)
A coarse filter is installed to clean the coolant from clogging impurities that can affect the smooth operation of the coolant.

Advantages and features of installing a water-to-water heat pump:

Take note: When installing the pump, you should pay attention to the direction of movement of the coolant in the system. As a rule, there is an arrow on the pump body for correct installation.

So, knowing all the characteristics of circulation pumps, as well as installation nuances, we can generally distinguish the following installation stages:

calculation of the required thermal energy to heat the house;
selection of a circulation pump according to calculations;
choosing a pump insertion location;
connecting a bypass with a pump to the system;
coolant injection;
starting the heating system and bleeding air through the central screw of the pump.

You must always adhere to the rules for installing and operating pumping units, otherwise no one will guarantee the correct distribution of thermal energy throughout your cozy home.

Watch the video in which an experienced user explains in detail how to properly install a circulation pump in a home heating system:

The main problem of heating systems in private homes has always been the difficulty of uniform heat distribution. Therefore, installing a circulation pump in heating systems has become more of a necessity dictated by common sense.

Let's look at installing main and additional pumps in an autonomous heating system.

1 How to install a circulation pump in a heating system?

Installing a pump in the heating system of a private house creates the necessary conditions for forced uniform circulation of coolant in the heating system, and ensures uniform heating of the radiators, regardless of the degree of distance from the boiler.

1.1 Installation options

The heating pump is installed according to two different schemes:

for one pipe;
for two pipes.

The single-pipe method provides a constant flow of coolant with small temperature changes. Installing a pump for heating using the second method will produce a variable flow of thermal agent and a high temperature difference.

Regardless of which method you choose, the equipment that will provide normal heating is almost the same and consists of:

boiler;
automatic air vent;
thermostatic valve;
radiator;
balancing valve;
expansion tank;
valve;
filter;
circulation pump;
pressure gauge;
safety valve.

An installed circulation pump in the heating system not only removes the inertia of long-term heating of the entire system and reduces the time for supplying hot water to radiators far from the boiler, but also:

almost instantly (thanks to forced pumping) it equalizes temperature conditions in all radiators in the house;
due to the sharp drop in intra-pipe pressure, it eliminates the appearance of air pockets that interfere with the normal circulation of coolants;
increases the efficiency of the entire heating circuit, regardless of the location of the radiators and their distance from the heating boiler.

1.2 Which heating pump is suitable for private home systems?

To choose the right device, it is worth considering two important details, namely: the pressure force with which the heating thermal agent circulates in the pipeline and the mechanical resistance of the hydraulics at the moment the pressure is created. Therefore, you need to take the device based on indicators that will be underestimated by 10% compared to the original indicators of the calculated value of pressure and resistance.

Otherwise, the installation of powerful heat pumps for heating leads to noise in the pipes, and the electric pump consumes significantly more energy than stated in the passport. In addition, the equipment will wear out much faster.

If you install a pump with a design power significantly less than the pressure and resistance indicators, then water heating will not be carried out normally. The required pumping volume cannot be met.

Since maximum efficiency can be obtained only at the maximum permissible speed of the electric motor, it is worth purchasing devices with the ability to electronically or manually regulate shaft rotation speeds. But, it is worth remembering that if there is a thermal valve in the heating circuit, and extraneous noise begins to appear at high engine speeds, then the pressure equipment must be switched to lower speeds.

Rule: pump control should be possible not only in the forced circulation mode, but also in the natural circulation mode of coolants inside the pipelines. Because if the equipment is connected only to the mains, without using an uninterruptible power supply, then a long power outage can lead to the coolant in the boiler overheating, destroying the heating circuit.

We also do not forget about the differences between pressure equipment with different rotors (wet and dry type). In devices with a wet rotor, all parts of the pump are lubricated by the coolant itself, which significantly extends its service life and reduces the noise level significantly.

You need to worry about noise insulation and maintenance of pressure equipment with dry-type rotors yourself. Additional information about the differences, advantages and disadvantages of different types of rotors can be found in other articles on our website.

2 Where and how to connect the pump?

Proper installation of the heating circuit occurs according to the following algorithm. The circulation pump must be connected to the pipes only with the shaft horizontal. You can connect pressure equipment to an underwater or return pipe, but the return pipe has its advantages, which we will discuss a little below.

A filter must be installed in front of the device to clean the coolant from dirt impurities. The suspension collector should be placed in a downward direction. The direction of the filter must strictly correspond to the direction of the arrows printed on the body of the device, which indicate the direction of water flow.

The lifespan of a circulation pump depends on the water temperature and on how much and how to install the pump correctly. The higher the temperature, the shorter the service life of the bearings. Therefore, the device should be connected to the boiler directly in front of it, on the return pipe and after the expansion tank.

2.1 How to install the pump so that it works when the power is turned off?

Install the device strictly parallel to the main circuit, without opening the circuit itself. In order for gravity inside the pipeline to work normally for the natural circulation of the coolant, install a circuit that is no less in diameter than Du-32.

To shut off the main boiler circuit to avoid running water in a circle between taps, install valves before and after the pressure device. Remember that if there is a long absence of electricity, you will have to switch to bypass from the pressure device manually. In this case, the bypass is disconnected from the main pipeline using two ball shut-off valves or taps.

A valve is required at the top of the bypass to pump out air. Install the terminals and control unit of the pressure device only in the “up” position. Connections that are made on threads must be treated with sealant.

But to ensure that the pump turns itself off during long power outages when no one is home, install a ball check valve. Its advantages over a conventional valve are that there is no loss in water pressure, which has to overcome the resistance of the spring mechanisms of a conventional check valve. The valve with ball should only be installed horizontally.

2.2 How to properly install a pump in a heating system? (video)

2.3 Additional pressure device

As a rule, additional pressure devices are installed in houses where old boilers are installed, or where the area of the house has increased due to the addition of new premises that were not previously included in the previous heating scheme. Additional installations are also effective for heating floors using a separate circuit to avoid air entering the heating circuit.

Don't forget about the little things that are required if you plan to install an additional pump. First drain the coolant and thoroughly rinse the pipes to remove any debris that has accumulated over the years of operation.

The principle of forced circulation of coolant has become an indispensable attribute of modern water heating systems. The fact that pumping water has an advantage over old gravity systems is no longer in doubt. Therefore, in most private homes, a circulation pump has already been installed or will soon be installed in the heating system. Not to mention newly installed utility networks, where it has been present since the design stage. Let's look at how to properly install the pump and connect it.

Where should the pump be installed?

The role of the pumping device in heating systems is clear to everyone. But questions often arise about the place of its installation. There are only two options here:

on the supply pipeline after the boiler and safety group;
on the return line directly in front of the boiler.

The number of supporters of installation in the return pipeline is large, but few of them can argue their position, just like those who like to install the unit in the supply. So, in practice, the installation location plays absolutely no role and does not have any effect on the operation and thermal power of the system. It is also erroneous to say that due to the lower temperature in the return the pump will last longer, that it is easier to pull than to push, and other statements in the same spirit.

In private homes, the temperature in the supply line rarely reaches 70 ºС, not to mention the estimated 90 ºС. The exception is the cold northern regions, but there the approach to heating buildings is somewhat more serious. The circulation units themselves are designed for high water temperatures and they jam for other reasons, for example, due to the low quality of the coolant containing various impurities. From a hydraulic point of view, the circulation pump can be installed on any of the two branches; the system parameters will not change.

Then why is the unit most often placed on the return line? Everything is quite simple. In the event of some malfunction and overheating of the boiler, the water in its tank will begin to boil, and the steam-water mixture will move into the system. But the pump can only pump an incompressible medium, that is, liquid. When steam gets into it, the pumping process will stop, the coolant in the network will stop, and the boiler will explode if measures are not taken.

Important. Most modern heat generators are well protected from overheating, there is nothing to worry about. In this regard, only solid fuel boilers pose a danger, so near them it is necessary to install a return pump only.

The pumping unit is installed in the network in compliance with certain rules and requirements. For the purpose of familiarization, we list all the rules for installing pumps:

The unit can operate in both vertical and horizontal positions. During installation, the direction of fluid flow indicated by the arrow on the housing must be observed;
When installing the unit, it is necessary to observe its orientation in space. The pump must be placed so that its rotor is in a horizontal position, and not with its head up or down, as shown in the figure below;
so that the pump can be removed for maintenance or repair, shut-off valves are installed before and after it;
the unit is installed on the bypass line, and a tap is placed on the direct line, then if it is turned off, the system will be able to continue operating without forced circulation;
if a circulation pump is installed in an open heating system, then it is better to place a strainer (dirt filter) on the bypass, in front of the pump, but after the tap. In pressure networks, the mud trap must be installed in front of the bypass, and when piping a solid fuel boiler - in front of the three-way valve.

There is one subtle point. In a scheme where forced circulation of the coolant was originally conceived, installing a bypass often does not make sense. After all, without a pump, water will still not flow through the pipes, since the slopes, diameters, and so on are wrong. Therefore, you can safely build the unit into the return pipeline between the expansion tank and the boiler, as demonstrated by the diagram for installing a circulation pump in the heating system shown in the figure:

The bypass line for the pump should be installed only in systems previously designed as gravity flow. The figure below shows the installation diagram corresponding to this case:

Advice. Sometimes, instead of a ball valve, a reed-type check valve is installed in a straight line of the gravity system. While the pump is operating, it presses the valve petal with its pressure and the straight line is closed. But as soon as the electricity is turned off, the pumping unit stops, the pressure drops and the valve in the straight line opens. Thus, the system switches to natural circulation mode automatically.

Work order

To install and connect the pump yourself, you need to follow the following procedure:

if the boiler is running, then you need to stop it and give the coolant time to cool;
empty the system or boiler circuit, if possible. When the piping of the heat generator is done correctly, there is no need to drain the water from it; it is enough to cut it off from the system using the appropriate fittings;
if the system is gravity-fed, then the bypass unit with a pump and taps can be assembled in advance;
insert the unit or just the pump into the supply or return pipeline, adhering to the rules set out above;
make an electrical connection to the circulation pump.

Advice. We will not reinvent the wheel and offer a wiring diagram here. This is available in the operating instructions for any unit, even those made in China.

Further actions consist of filling the system with water and bleeding air from it using Mayevsky taps and valves. Next, it wouldn’t hurt to inspect the installation site to detect leaks. If they are not there, then you can safely put the circulation pump into operation. Do not forget to open the valves that shut off the unit and shut off the direct line if it is installed on a bypass.

Conclusion

At first glance, you might think that installing a circulation pump correctly is not difficult. This is actually true if you have experience in installation work. When there is no such experience, we advise you to carefully study the documentation supplied with the product by the manufacturer.