DIY circulation pump repair

In detail: do-it-yourself repair of a circulation pump from a real master for the site my.housecope.com.

The circulation pump is often used in individual heating systems in private houses. This equipment makes it possible to efficiently circulate the coolant along the circuit, which ensures a stable temperature throughout the room. The quality of heating depends on the operation of the device.

Circulating pumps serve for a long time and are rarely damaged. However, if malfunctions occur, you can repair the device yourself. It is also important that pumps of different models have the same principle of operation, are subject to the same breakdowns, therefore, the methods for their elimination are the same.

In large rooms, the pipes are long and the water circulates in the system slowly, having time to cool down before returning in a closed loop back to the boiler for reheating. To solve this problem, they resort to the help of circulation pumps, which forcibly force the coolant to move faster along the contour.
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To repair the equipment yourself, you should know its device:

Steel body, elongated horizontally. It contains all the elements of the system. The body can also be made of aluminum alloy or stainless steel.
Electric motor and rotor housed in a housing.
Impeller with blades fixed to the rotor. The blades are curved in the opposite direction from the movement of the wheel. This part is made from durable polymers.

When the pump is turned on, water in the circuit is drawn into the inlet by the rotation of the wheel. In the chamber, centrifugal force acts on the water, pressing it against the walls of the chamber and pushing it out. After that, the pressure drops and water is pumped back into the pump.

Video (click to play).

The device of modern circulation pumps

With such a continuous cycle of operation, the temperature in the heating system is constantly kept at the same level. This saves fuel or energy costs.
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What breakdowns can occur and how to repair the circulation pump with your own hands? Let's figure it out.
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Foreign object in the impeller chamber.
Prolonged downtime of the apparatus led to oxidation of the rotor shaft.
The power supply to the device terminals is interrupted.

In the first case, you can eliminate the malfunctions by carefully removing the device and unscrewing the housing in the impeller area. If there is a foreign object, remove it and turn the shaft by hand. To avoid re-entry of foreign matter, a filter should be installed on the nozzle.

The humming of the pump can also be observed during prolonged downtime and shaft oxidation. It is necessary to thoroughly clean all oxidized areas and lubricate the movable parts of the working unit.

The circulating pump hums even if the power supply fails. First check the voltage with a tester. If the cable is damaged or broken, it should be replaced. If the cable is in order, look at the voltage at the terminals. The infinity icon on the tester indicates a short circuit. A lower voltage means an open winding. In both cases, it is necessary to replace the terminals.
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The pump does not work when there is no mains voltage. The tester checks the voltage, as well as the correct connection of the device to the power supply.

Circulation pump shaft

If there is a fuse in the pump, there is a risk that it will burn out from power surges. If this happens, replace the fuse. It is advisable to install a reliable stabilizer.
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Limescale deposits between the moving parts of the appliance.
Incorrect connection of the pump in the area of the terminals.

The pump can turn on, but also stop immediately if there is scale. Remove limescale and lubricate the joints between stator and rotor.

In the second case, check the tightness of the fuse on the device. It is removed and all clamps are cleaned. All wires must be correctly connected in the terminal box.
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If the pump is noisy, it could indicate the presence of air in the system. It is necessary to bleed the air from the pipes, mount a unit in the upper part of the circuit so that the air is released automatically.

The pump can also make noise due to wear on the impeller bearing... It is required to disassemble the body of the device, and, if necessary, replace the bearing.
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If the activation of the pump is accompanied by vibration and noise, then the reason is insufficient head in a closed circuit. You can solve it by adding water to the pipes or increasing the pressure at the pump inlet.
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With a low pressure or when the pump almost does not pump the coolant, check the direction of rotation of the impeller in the body of the apparatus. If the impeller turns incorrectly, then you made a mistake when connecting the pump to the terminals in phases, if you use a three-phase network.

A decrease in head may result from the high viscosity of the coolant. At the same time, the impeller experiences increased resistance and does not work well, not at full strength. It is necessary to check the mesh filter and clean it. It is also advisable to check the cross-section of the pipes of the holes. After that, you will need to adjust the correct parameters of the pump.
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The pump will not turn on if there is a power problem. It is necessary to check the phases and fuses. If they are in order, then the drive winding has burned out. In this case, you will have to seek help from specialists.

The internal surfaces of the pump must be free of rust

When diagnosing equipment, you can use the indicator - a tester of the rotation of the circulation pump shaft. It allows you to make sure that the pump is working without being connected to the mains.
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The temperature of the pump must be the same as the temperature of the pipes of the heating system. If the circulation pump heats up and its temperature is higher than that of the pipes, then there are errors in installation or a problem with operation. Let's consider why the device is heating up.

If installed incorrectly, the pump starts to overheat immediately after switching on. Installation errors are the easiest to spot.
Clogged loop. Rust and various deposits accumulate in the system. This leads to a narrowing of the diameter of the passage for the coolant. The load on the machine increases and the engine overheats. Preventive maintenance of the system will be required.
Rust, debris, limescale in clogged communications can get into the pump and jam the electric motor, causing it to warm up. Disassemble and clean the device, otherwise the motor coils will quickly fail.
The pump is also heating up due to a lack of bearing lubrication. Under these conditions, they wear out much faster, thereby reducing the service life of the entire apparatus. The motor is seized. The pump should be taken to a workshop.
When the mains voltage is below 220 V, the pump overheats and can quickly fail. Determine the voltage in the network as soon as the engine starts to warm up in order to immediately exclude or confirm this problem.

If the circulation pump heats up, you do not need to disassemble it immediately. First, measure the voltage in the network. At normal voltage, the system is washed with caustic soda, leaving it in the pipes for an hour, and then drained. If the pump is still warming up, you will need the help of specialists.
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In order for your pump to serve for a long time and reliably, you should follow the operating rules and carry out regular preventive maintenance. The apparatus should be inspected periodically:

If a leak is detected at the joints, replace the gaskets and seals.
Check the grounding.
Extraneous sounds should not be present when the engine is running.
There should be no strong vibration.
The line pressure is measured.
The pump must be dry and clean.

Every two to three years, the device is cleaned, all of its components. Regarding models that can be disassembled. Pumps with one-piece or pressed-in casing cannot be repaired, and if a breakdown occurs, it is replaced with a new one. How to disassemble a circulation pump yourself?

Testing and repair of the electrical unit of the circulation pump

To do this, you need a hex wrench, a flat screwdriver (slotted) 4 and 8 mm, a Phillips screwdriver.

First, all the water is drained from the system, the pump is dismantled and then they are disassembled.

Using a wrench or a screwdriver, unscrew 4-6 bolts on the body at the point where the pumping part is connected to the shell.
The shell is removed, while the impeller remains on the rotor shaft with the engine.
Drainage holes are found around the perimeter. There should be four of them. With a slotted screwdriver, little by little pry the jacket of the electric motor compartment under the impeller. The shaft with the rotor and the impeller must come out of the grooves and the stator cup.

The disassembly of the unit is now complete. Next, the rotor, impeller, shell are cleaned from scale and plaque without damaging the parts. Do not use coarse abrasives. It is recommended to clean the parts with a hard polymer bristle brush. You can use cleaning agents that contain a weak solution of hydrochloric acid. Sometimes they use fine emery - "zero".

Popular manufacturers of circulation pumps are Webasto, Wilo, Ggrundfos, Dab. Models of these brands are reliable, and damage can occur only if the operating conditions are not followed. If you still have to resort to repairing the circulation pump, then finding and purchasing the corresponding parts on the Internet will not be difficult. A repair kit for the circulating pump u 4814, which is very popular in the modern market, like other models, can be ordered in many online stores.
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In a forced circulation heating system, the heart is the circulation pump. The availability of heating and its quality depend on its stable operation. The same applies to closed hot water supply systems with a constant flow of water in the pipes between the boiler and the storage tank. During operation, the question inevitably arises of how to carry out maintenance and repair of the circulation pump so that it continues to work stably and trouble-free.

For the normal functioning of the pump, the following measures must be taken:

Correct operation, taking into account all the rules established by the manufacturer of the pumping equipment.
Prevention and maintenance of the pump.
Diagnostics and repair in case of pump failure.

The more accurately the operating rules are followed and the more regular pump maintenance is performed, the less often you will have to think about repairing or replacing it.

A number of simple requirements apply to any circulation pump:

Do not allow the pump to idle in the absence of water. Applies to both wet and dry pump.
The pump must not be allowed to operate with a stopped flow of water, for example, if a valve is closed in front of or after the pump.
It is necessary to determine the optimal mode of operation, taking into account the maximum and minimum capacity of the equipment.
It is important to comply with the manufacturer's requirements for the nominal water pressure in the system.
The coolant temperature should not exceed 65 ° C. Therefore, the circulation pump is installed on the return line in front of the boiler, where the already cooled water flows. When a predetermined threshold is exceeded, the process of deposition of hardness salts on the inner surfaces of the pump is accelerated many times over.
Prolonged downtime should not be allowed. About once a month or two, it is advisable to turn on the pump for 15 minutes. If this is not done, then during the oxidation process, the risk of shaft seizure increases.
It is unacceptable to use a circulation pump for pumping dirty water with the inclusion of dense particles in suspension. A coarse filter must be installed, or the purity of the water or heat carrier is monitored in other ways.

In operating mode, the pump should have a uniform sound of the operating drive and a constant value of the head at the outlet, which is controlled by the installed pressure gauge. With good handling, even the simplest circulation pump can operate for up to 5 years until its main elements wear out.

Almost all circulation pumps are of centrifugal type. They have an impeller fixed on the motor shaft and placed in a special “shell” chamber. The entrance to the shell is located in the center, while the exit is the outer edge of the shell with a channel extending around the circumference in the direction of motion of the impeller. The engine spins the impeller, and the water, under the influence of centripetal force, rushes from the center to the edges of the sink from inlet to outlet.

Structural elements of the pump:

pumping part, sink and impeller fixed on the shaft;
electric motor;
electronic control unit.

The most susceptible to wear is the moving part of the pump - the motor shaft and impeller, as well as the bearings on which they are attached.

Long service life and trouble-free operation is possible only if proper operating conditions are observed and the pump is regularly prevented. Service refers to the periodic inspection and cleaning of the pump. Inspection for deviations in work should be carried out at least once a quarter, that is, twice during the heating season. It is advisable to clean it every two to three years, depending on the quality of the water and the conditions in which the pump operates.

During the entire period of operation, it is advisable to periodically check the operation of the pump:

The connections are checked for leaks. If detected, gaskets and seals (tow, FUM-tape, etc.) are replaced.
The presence and condition of grounding is visually checked.
The sound of a running engine should not be accompanied by clanks or bumps, extraneous sounds.
The engine should not vibrate too much.
The line pressure is checked and its compliance with the nominal one.
The housing must be clean and dry. If this is not the case, then external cleaning should be carried out, the electronic unit should be checked for flooding and the reason why the pump was wet should be eliminated.

It is advisable to clean the pump, including all its elements, about once every two to three years. This only applies to disassembled models. There are pumps with a pressed-in or one-piece, welded casing, which does not involve repair or disassembly. Such units fail and are then replaced with a new assembly. It is advisable to entrust this work to the service center. However, if you have the skills and the tool, you can do everything yourself.

Before disassembling the pump, water is drained from the system or a separate section in which the pump is involved is drained, dismantle it and then proceed to disassembly.

With a hex wrench or a Phillips screwdriver, 4-6 bolts are unscrewed along the perimeter of the engine housing at the junction with the pump shell.
Remove the shell, while the impeller will remain on the rotor shaft with the motor.
Locate four drainage holes around the perimeter. Using a narrow slotted screwdriver, pry up the jacket of the engine compartment under the impeller little by little around the perimeter. As a result, the shaft with the rotor and the impeller will come out of the slots and the stator cup. You can help yourself if you unscrew the protective plug on the outside of the pump, insert a screwdriver into the slot on the end of the shaft and knock the shaft out of the support bearing with light blows.

The analysis is now complete.Now it is necessary to clean the surface of the rotor, impeller and the inner surface of the shell from plaque and scale, if any, just without damaging the surface of the parts. It is not permissible to use coarse abrasives. Better to act with a brush with a polymer hard bristle. Cleaning agents containing a mild hydrochloric acid solution may help. In extreme cases, the smallest emery is used - "zero".

For glandless pumps, it is important to check the cleanliness of the bore inside the shaft and the drain holes located in the protective jacket separating the area of the pumping part and the motor. The liquid enters the rotor just through these holes and then returns through the inner channel, if they are clogged, the cooling of the engine suffers.

For pumps with dry rotor waterproofing of the support bearing is important. If a leak is found from the pump block to the stator block, then completely replace all gaskets and seals inside the device.

The condition of the bearings on which the shaft rests is checked. If they are already broken in order, they will need to be replaced, which is extremely difficult to do at home, you will have to contact a service center.

All seals and gaskets inside the pump should be checked for wear and replaced if necessary. Once all the elements are cleaned and checked, the assembly is carried out in the reverse order.

The circulation pump needs cleaning

By the way the pump works, sound, vibration or a change in pressure, outlet pressure, it is necessary to accurately determine the malfunction and eliminate the cause.

Do-it-yourself heating circulation pump repair is a rather difficult task. To do it correctly, you need to understand the design and features of such equipment.

Pump circulation devices, often called pumps, are popular among owners of summer cottages, private housing construction, apartments with autonomous heating, and country cottages. The choice of such devices is quite large these days. Circulation pumps differ from each other in technical characteristics. However, their overall design remains unchanged.

The device of the circulating pump is as follows: the device has a housing made of carbon steel, stainless steel or strong aluminum-based alloys. The pump is made elongated horizontally. An electric motor with a rotor is installed in the housing. The motor power is quite high. It varies depending on the equipment model. The rotor is equipped with an impeller made of ultra-strong polymer compounds or steel. It is equipped with special blades. They bend in the opposite direction to the rotation of the wheel.

An electric motor with a rotor is installed in the pump housing

In some cases, the pumping equipment assemblies are not enclosed in one casing, but in several separate blocks. Such pumps for two- and one-pipe heating systems are called console. There are two types of pumps - wet and dry. The first of these devices are made in the form of a monoblock. They have an affordable cost, they work almost silently. Dry pumps are in most cases made of cantilever type. The electric motor is installed in a separate unit. The rotor of the engine is rotated through a special coupling. Dry pumps are structurally more complex due to the presence of a drive mechanism.

The principle of operation of the described devices:

After starting, the electric motor starts to rotate the impeller on the rotor.
The liquid enters the central part of the pump device.
The blades on the impeller throw the used heat carrier (oil, water) to the outside of the housing.
Centrifugal force begins to act on the liquid. Due to this, the coolant enters the outlet pipe.

After all these operations, a drop in pressure is observed in the chamber, due to which the pump receives another portion of the pumped liquid. This ensures the continuity of the pump.

Repairing circulation pumps requires dismantling and (usually) disassembling them. Removing the pump is easy. It will be necessary to de-energize the device, close the bypass heating pipe - bypass, if one was installed, and then carefully unscrew all the shut-off valves that fix the pump. Then you can safely dismantle the pump.

Disassembling the device will have to tinker a little longer. But this operation is quite feasible. Stock up in advance with a hexagon, a Phillips screwdriver, a liquid wrench - a special aerosol composition that is applied to fasteners that have become stuck during operation and allows you to unscrew the latter without difficulty. If the pump has not been disassembled for a very long time, the use of the specified aerosol is mandatory. How to disassemble a circulation pump?

Follow the instructions below:

1. Unscrew the bolts that secure the mechanism cover. Don't forget to use a liquid key!

2. Remove the cover. The rotor is located under it. Its fastening is most often done with bolts. Less commonly, special clamps are used.

3. Unscrew the bolts (release the locking elements).

Disassembly of the pump is complete. All units and individual parts of the circulation device are located under the rotor. It is not necessary to disassemble the pump down to the bolts. First, you should decide which element is out of order, and only then remove the specific part that needs to be replaced or repaired. If the entire pump needs to be replaced, simply dismantle it. It is not necessary to completely disassemble the mechanism. Remove the equipment that has failed. Install a new one in its place.Pumps from different manufacturers have been shown to have the same design. Therefore, their faults, as a rule, are the same. Many users are faced with the fact that the circulation device starts to hum when starting, but the rotor does not rotate. A similar problem occurs due to:

Incorrect connection of electrical wiring or lack of power on the terminals of the pump. The problem is solved by checking the power supply with the tester and reconnecting (correct!) Cables.

Oxidation of the motor shaft. This phenomenon is most often observed in cases where the pump has not been used for a long (several years) time. Do-it-yourself repair in such a situation will be as follows - turn off the power, drain the water from the pipeline and the pump itself, disassemble the electric motor (remove the cover and rotor). Now the main thing. You need to take a screwdriver and turn the rotor all the way into the working notch. The operation can also be performed by hand if the mechanism rotates without difficulty.

Foreign objects falling into the mechanism. You need to disassemble the cover and rotor. Remove foreign body. After that, be sure to replace the mesh filter. As a rule, a foreign object will disable it.

Circulation device in the heating systemIf the pump starts up normally and then stops, it is most likely not properly connected to the terminals. Check it out. Make a proper connection if necessary. Another reason for the described breakdown is the appearance of scale between the rotating units of the mechanism. Disassemble the unit, remove the existing limescale, lubricate the joints of all parts with oil. Sometimes the pump stops due to a loose fuse. It is necessary to dismantle this element and clean the clamps securing it.A defective fuse is often the reason the pumping equipment will not turn on.Check the terminals, measure the voltage at the terminals with a multimeter. If the fuse is broken, replace it.Such situations are often encountered due to power surges in the power grid. If you do not want to constantly put a new fuse, connect a stabilizer to the equipment. It will reliably protect the system from voltage surges.The pump may make a loud noise when starting up. This signals that air has entered the closed circuit of the circulating system. They prevent such a phenomenon by installing specials. node in the pipeline. Such a small element eliminates the possibility of air congestion in the system. If a special assembly has not been installed, you will have to purge the pipeline. Severe noise, as well as perceptible vibration, sometimes occur due to wear on the bearing, which is placed on the impeller wheel. Disassemble the housing of the unit, analyze the condition of the bearing, replace it with a new one if necessary.Circulation pump repairWhen the pump does not provide the required pressure of the coolant, the reason lies in the wrong (in the opposite direction) rotation of the impeller. This problem only occurs when pumping equipment is connected to a 380-volt mains supply. The solution is to connect the wire to the correct phase. Also, the head decreases with an increase in the viscosity of the coolant. In situations like this, the wheel encounters high resistance and cannot fulfill its function. You will need to remove the strainer from the pump, clean it or replace it.As you can see, it is quite possible to repair the circulation pump with your own hands. Of course, when it comes to common breakdowns. In other cases, it is better to entrust the restoration of the pump to the specialists of the service centers.Proper handling and regular maintenance of pumping equipment eliminates the need for repairs for many years. Consider the following when operating your pump:

Do not start the pump if the piping is not filled with thermal fluid.

Turn on the circulation equipment at least once a month for 15–20 minutes. Prolonged downtime of the pump is guaranteed to lead to malfunctions of its individual components and mechanisms.

Follow the manufacturer's recommended volume of pumped liquid. If the device is designed for 100 liters of coolant per hour, it is forbidden to pump more water through it.

Before the start of the heating season, check the system for leaks, the correct connection of the circulation unit to the mains. Carry out test runs of the pump to ensure that there is no vibration or abnormal noise.

DIY circulation pump repair

Circulation pumping devices are very popular with private house owners and summer residents. The range of pumping equipment is quite wide, but the general principles of the device are the same. Such equipment can stop from minor breakdowns. Take a broken pump to a service center? It costs money, and in many regions there are simply no service companies. Therefore, the household owner of the house must know how to repair the circulation pump with his own hands.

To understand how to independently disassemble, maintain, repair a circulation pump, you need to know its structure. Such equipment is arranged as follows:

all units and mechanisms are located in the case, which is made of steel (mainly stainless), aluminum and other alloys;
inside the case is located rotor motor;
a wheel with wings is installed on the rotor - impeller, which is usually made from technical polymers.

Circulation pump device

After turning on the electrical circuit, the engine begins to rotate the rotor with the impeller attached to it. Liquid is supplied to the central part of the pump. The blades rotate and throw water or other coolant to the outside of the housing. Under the action of centrifugal forces, the liquid moves and enters the pump outlet.

Circulation pump in the heating system

There are currently two main types of circulating pumping devices on the market.

"Wet type" - in such equipment, the rotor is completely immersed in the pumped liquid. A significant advantage of this configuration is the cooling of the rubbing and heating parts by contact with the liquid. Such equipment works quieter and costs less. When installing it, it is necessary to maintain the position of the housing specified by the manufacturer (usually horizontal), since the rotor must be completely immersed in the liquid. Also, "wet" devices are easier to maintain, but very sensitive to the lack of fluid in the system (running "dry" can quickly damage the pump).
"Dry type" - in such devices, the pump motor is placed in a separate compartment or module, and the transmission of torque to the rotor is carried out through the drive device (coupling). Dry-type pumps are more efficient, but also have a more complex design. A dry pump can operate without damage and without fluid in the system, but this operation will result in increased wear on the drive.

Also circulation pumps can be divided into types according to the type of execution:

monoblock;
console, consisting of separate blocks.

In order not to disassemble and repair your equipment once again, it must be properly operated.

Never run the pumping device without liquid in the heating pipes.
Keep the volume of water pumped by the pump within operating specifications. Excess or decrease in the volume of pumped water, in relation to the indicators specified in the technical passport, is unacceptable. If the pump is designed to pump from 5 to 100 liters of water per hour, pumping 3 or 103 liters of water will wear it out a lot.
If your pump has been idle for a long time, turn it on for about a quarter of an hour once a month. This will help prevent oxidation of moving parts and subsequent damage.
Maintain the temperature in the water supply lines no more than 65 degrees. If the temperature of the coolant is exceeded, sediment can damage the moving parts of the pumping device. Water temperature over 65 degrees (for example, 70-80 ° C) contributes to the rapid wear of the equipment.

From time to time, preferably at least once a month, it is necessary to carry out an external examination and check the quality of your circulation pumping device.

Pump device option

Turn on the pump and check that there are no abnormal noises and excessive vibration during operation.
Check the pressure of the heating medium delivered by the pump. It must correspond to the indicators stated in the technical passport.
Make sure there is no excessive heating of the electric motor of the device.
Check the threaded flanges for grease and restore if necessary.
Make sure there is a ground connection between the pump body and the corresponding terminal.
Inspect the pump from all sides and make sure there are no leaks. Typically, such vulnerabilities are the interface between the pipeline and the pump housing.Check the level of tightening of the bolts and the normal condition of the gaskets.
Examine the terminal box. All wires must be securely fixed. The presence of moisture in the unit is unacceptable.

In circulating pumping devices, there are a number of typical malfunctions that you can eliminate yourself. Each block will describe the symptoms of a malfunction, its causes and DIY repair steps.

The reason may be oxidation of the motor shaft during prolonged pump downtime... Troubleshooting instructions.

Turn off the power to the equipment.
We remove water from the pump and pipelines adjacent to it.
Remove the screws securing the housing and the motor.
We dismantle the electric motor complete with the rotor.
We turn the rotor by hand, or with a screwdriver, resting against the working notch.

The next reason for such a malfunction may be ingress of foreign objects.

Turn off the power to the equipment.
We remove water from the pump and pipelines.
Remove the screws securing the housing and the motor.
We remove the foreign object.
We protect the inlet pipe of the pump with a mesh filter.

Also, the reason for the lack of rotation can be lack of power supply... To do this, we check with a tester that there is power at the terminals in the box and that the electrical wires are connected correctly.

The main reason for such a malfunction can be lack of power supply or insufficient voltage in the network... To eliminate it, it is necessary to check the voltage at the terminals with a tester and, if necessary, the correct connection of the device to the power supply.

Many electric pumps are fitted with a fuse. In case of power surges, it burns out and requires replacement.

This can be caused by limescale deposits between the stator and the rotating rotor. The malfunction is eliminated by dismantling the electric motor and cleaning it from limestone deposits.

The cause of such a malfunction may be the presence of air in the pipeline of the heating system. To eliminate it, it is necessary to release air from the pipes. For automatic venting, it is recommended to install an automatic unit in the upper pipe segment.

If a sharp noise is accompanied by increased vibration, then it is recommended to increase the pressure at the inlet to the pumping device. Insufficient head can be compensated for by an increase in the level of the coolant in the system.

The cause of such a malfunction is usually a strong wear of the bearing that ensures the rotation of the impeller. The malfunction is eliminated by replacing the worn bearing.

The cause of such a defect may be the wrong direction of rotation of the wheel with blades. The reason for this phenomenon is usually an incorrectly connected phase when three-phase equipment is connected.

Also, a decrease in head can be caused by an increased viscosity of the coolant, then the impeller encounters too much resistance. To eliminate it, it is necessary to clean the filter on the inlet pipe from deposits, check the cross-section of the inlet pipeline and set the necessary pump adjustment parameters.

Most likely, the cause of such a malfunction may be the incorrect connection of the wires in phases in the terminal box. The fuse on your pump may not be tight enough. Remove it and clean the clips.

In order for your equipment to work without interruption during the cold season, it is necessary to carry out routine maintenance before the start of the heating season.

Check if the pump is correctly connected to the heating pipe network... The pumping equipment must be installed in such a place of the irrigation network, where there is a minimum possibility of air congestion. It is rational to place it on the return line, in front of the heating boiler.
Before using make sure that all network connections remain tight... To prevent the gaskets from drying out, the inlet and outlet branch pipes are covered with a preservative lubricant during a break in operation.
Check the condition of the filter in front of the pump inlet... Replace or clean if necessary.
Check if the device is properly connected to the power supply... Not only the tightness of the contacts on the terminal box, the serviceability of the fuse, but also the correctness of the phase connection and the value of the operating voltage in the network are checked. It is best to check these characteristics with a tester.
Before starting to operate the heating circulation pump without fail do a test run, which must confirm the complete tightness of the system and the serviceability of all its components and equipment.

If, during the test run of the equipment, shortcomings of the pumping device are revealed that cannot be eliminated without dismantling and disassembling it, you will have to perform the following operations.

At the preparatory stage, the pumping equipment is de-energized. When installing the pump, a bypass is built into the pipeline system - a bypass heating pipe. It is closed during normal operation. For long-term repairs, it may be necessary to connect an additional pumping device to the system.
Unscrew the shut-off valves securing the pump, remove it.

Dismantling the pump before repair is especially necessary, your heating pipelines are made of metal-plastic. Over-the-air repairs can damage such pipes.

Pumping equipment diagram

With a serious repair of pumping equipment, it is necessary not only to dismantle it, but also to disassemble it. It is performed in the following sequence.

The circulating pump cover is fixed to the body with bolts. These can be Phillips or Allen screws. During operation, the bolts can "stick". This problem can be solved with the help of specialized aerosols, also called "liquid key". It is applied to the bolt and can be easily unscrewed after a few minutes.
Remove the cover. Before us is a rotor with a rotor fixed on it with a wheel with blades. Usually it is held on by clamps or bolts. Remove it and you will get access to the "insides" of the pumping equipment.
Inspect the pump, identify the faulty unit and replace it.

It is necessary to carry out self-repair of circulation pumps only after the expiration of the warranty period or if it is impossible to obtain qualified technical assistance. A number of pump assemblies are quite difficult to find commercially. This is usually caused by the trade policy of the manufacturers, so be prepared for the fact that in some cases it is cheaper to purchase new equipment rather than fix broken ones.