How to check the health of the heating system circulation pump

From the author: Hello, dear readers! The circulation pump plays a very important role in the heating system of almost any private home. Without this device, the coolant flows through the pipeline at a very low speed, resulting in significant wasted thermal energy losses. The result is an unevenly heated house and the danger of freezing of pipes located in non-residential premises - in the attic, basement, etc.

The circulation device easily prevents the mentioned problems. It increases the speed of the coolant flow, thereby giving the liquid the opportunity to quickly run along the route and deliver the required amount of heat to all radiators and other similar equipment. Naturally, to perform this function efficiently, the device must work flawlessly. That's why every homeowner should know how to test a heating circulation pump.

As you know, timely diagnostics can detect a malfunction even in the early stages of development, so a preventive inspection will help protect the device from possible serious damage. The nice thing is that performing the check will not take much of your time and effort, and almost any owner can handle the necessary repairs. Of course, to do this you need to have some information - and you can get it from today's article.

How to check the heating circulation pump for serviceability

You can check in the following ways.

Ease of inclusion

To examine the performance of the equipment, it is recommended to check whether it is easy to turn on. After seasonal downtime, the condition of the unit must be checked.

To do this, it is recommended that after switching on, listen to the sounds that the equipment makes during operation. If there is no damage, the unit operates quietly .

If you hear various sounds, you will have to check the contamination of parts , the amount of water in the system, etc.

Presence of noise during operation

If the circular pump makes noise, it requires diagnostics or complete replacement. Sounds occur due to malfunction of the rotor or impeller , which can render the entire heating system unusable.

Sometimes noise occurs due to voltage drop . This happens due to imbalance and synchronization, which leads to uneven movement of the coolant.

Attention! Diagnostics are carried out only by a specialist .

If operation is stable, but the device still makes noise, it is recommended to check:

Is the operating power of the unit equal to the initial values? If the calculations are similar, then the coolant moves too quickly or slowly, which leads to noise.
Is the motor rotor in a horizontal position?

Bearing operation

Bearings wear out and vibrate heavily.

They are responsible for rotating the impeller, so if the part is no longer suitable for use, it needs to be replaced.

Also, bearings sometimes become damaged and make knocking or squeaking noises. To eliminate the problem, disassembly and washing are carried out. A special worker does this.

When is a performance check needed?

After another long period of inactivity , the unit needs to be checked; if it is delayed, there is a risk of not only losing heating, but also seriously damaging the equipment.

How can you eliminate typical circulation faults?

Let's see exactly how they can be expressed and what the user should do in a given situation.

So, the main malfunctions of circulation pumps and ways to eliminate them.

The pump motor cannot be started, but no humming or other “electrical” sounds can be heard.

In this case, the first suspect is the fuse, if your model has one, of course. It reacts sensitively to power surges, which, alas, are not uncommon in suburban areas, and at the slightest threat to the engine it melts, opening the electrical circuit. After replacing the fuse, the pump will return to operating condition.

If the fuse is intact, you should “ring” the power cord and electrical wiring, and also check the condition of the fuse or circuit breaker in the junction box. Perhaps it or some section of the wire needs to be replaced.

If everything is in order with the wiring, the electric motor winding may have burned out. Its condition is checked by measuring the resistance (using a multimeter). When connected to the contacts of the working winding, the device should show 10 - 15 Ohms.

Some pumps, in addition to the working one, also have a starting winding. Its resistance should be 35 - 40 Ohms.

If the meter display shows “infinity” instead of the indicated numbers, then the winding under test has burned out. If the multimeter readings, on the contrary, tend to zero, then there is an interturn short circuit. In this case, when you try to turn on the pump, the fuses in the panel will trip.

The cause of the pump “strike” may also be a breakdown of the non-polar capacitor present in the starting winding circuit. In good condition, it has a capacity ranging from 10 to 40 μF. If the meter readings differ from normal, the part must be replaced.

You can undertake electrical repairs yourself if you have sufficient experience in this matter. In most cases, you have to trust specialists.

The pump hums, but the shaft with the impeller does not rotate

In such a situation, the pump must be turned off, otherwise the motor winding may burn out. There may be several reasons for such a breakdown:

As already mentioned, the shaft may become stuck due to prolonged inactivity. Also, an impeller that does not work for a long time can stick to the housing. In such a situation, you need to disassemble the pump and force the shaft to rotate. To allow the user to do this, there is a notch on the shaft that can be grabbed with a screwdriver. If you were unable to find it, disassemble the discharge mechanism and turn the shaft, holding the impeller itself.
The impeller may become stuck due to a foreign object entering the chamber. By removing it, you will resume system operation.

To prevent this from happening in the future, install a dirt filter at the pump inlet.

The operation of the pump began to be accompanied by an unusual noise

This is exactly how air accumulated in the system can manifest itself. To remove it, it is most rational to equip the heating circuit with an automatic air vent. In the meantime, you will have to bleed the air manually. Immediately after this, the pump will stop making noise.

The pump vibrates a lot during operation

If you observe such a phenomenon, it makes sense to check the condition of the bearing.
Most likely it is worn out and needs to be replaced. Bearings are always installed on the shaft and in the mounting hole with interference, in other words, they are pressed.

In factories and workshops, a special tool is used for this - a puller.

Home craftsmen who do not have such a contraption knock out the bearings with careful blows of a wooden hammer or make a primitive puller themselves. It consists of a pair of plates with holes into which two studs with nuts are threaded. One plate rests against the end of the shaft, the other against the bearing (it is put on the shaft, for which a hole of the appropriate diameter is made in it), after which it is necessary to tighten the nuts on the studs one by one and very gradually.

Pump vibration can also be caused by excessive cavitation. To solve this problem, it is necessary to increase the pressure at the inlet to the unit by raising the coolant level in the circuit.

A heating circulation pump is effective even in homes with a simple heating system, so you need to know how to choose the right device. Circulation pump for heating: how to choose, we will consider in this topic.

Let's look at the essence of a heating system with natural circulation using this link.

A heat pump for heating a residential space is not the most common option, but it is excellent for economical heating. In this article https://microklimat.pro/otopitelnoe-oborudovanie/otopitelnye-pribory/teplovoj-nasos-dlya-otopleniya-doma.html we will look at the principle of operation of the unit and give an example of calculating a collector.

Pump design elements

The basis of any device is its design. The circulation pump is not a very complicated device. It consists of several elements:

frame. It is a cylindrical product, for the manufacture of which brass, bronze, stainless steel or cast iron can be used. Any of these metals perfectly resists corrosive processes, which is extremely important given the proximity of the liquid to the device. In addition, the durability of these materials is also excellent. Cast iron is especially respected in terms of longevity - it can last for more than half a century. But its problem lies in its instability to temperature changes. In principle, given the autonomy of the heating system of a private house, one can hope for their absence, since the operating mode is controlled by the owners of the home. But force majeure still happens, and they can lead to cracking of cast iron. The other metals listed above do not have this problem. Of course, their cost is a little higher, but you don’t have to worry about the sudden appearance of cracks on the pump body;
electric motor with rotor. It is located inside a cylindrical body and is, in fact, the heart of the device. Engine power varies between models. In general, it is the main criterion for selecting a circulation pump. The power rating of the device must correspond to the needs of the specific heating system in which the device will be installed. Otherwise, it may not cope with the responsibilities assigned to it. Speaking about the rotor, it should be noted that it can be “dry” or “wet”. The difference lies in its location. The “dry” rotor is placed in a separate pump unit, where it is reliably protected from direct exposure to liquid. “Wet”, on the contrary, is placed directly into the coolant. When choosing a specific device, it is important to know that “dry” varieties have much higher performance, their efficiency is about a third higher than that of “wet” ones. But they have a very important drawback - high noise levels. The hum produced during the operation of such a rotor can cause significant inconvenience to people even during the daytime. What can we say about the night, when sounds travel much better. In general, it is not recommended to place such a device near living rooms, since the discomfort of people will be very great. Circulation pumps with a dry rotor can be installed in a separate boiler room, which is located away from the bedrooms. If it is not possible to equip such a room, or the dimensions of the house do not allow a serious separation between the residential and non-residential parts of the building, then it is better to install a pump with a “wet” rotor in the system. It will consume more resources due to lower efficiency, but it will not get on your nerves with constant loud noise;
impeller with blades. It is due to the latter that the coolant moves. The wheel, located on the rotor and made of durable stainless materials, begins to rotate when the electric motor is turned on. In this case, the blades scatter the liquid along the walls of the cylinder, from where it then goes into the pipeline under the influence of centrifugal force. At the same time, the pressure level sharply decreases, resulting in the flow of a new portion of liquid.

Prevention and Maintenance

Long service life and trouble-free operation are possible only if proper operating conditions and regular maintenance of the pump are observed. Maintenance means periodic inspection and cleaning of the pump. Inspection for abnormalities in operation should be carried out at least once a quarter, that is, twice during the heating season. It is advisable to perform cleaning 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:

Connections are checked for leaks. If identified, 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 clangs, knocks, or extraneous sounds.
The engine should not vibrate much.
The pressure in the line is checked and its compliance with the nominal one.
The housing must be clean and dry. If this is not the case, then you should carry out external cleaning, check the electronic unit for flooding and eliminate the reason why the pump is wet.

Approximately every two to three years, it is advisable to clean the pump, including all its elements. This only applies to models that can be disassembled. There are pumps with a pressed or solid, welded casing that does not require repair or disassembly. Such units fail and are then replaced with a new assembly. It is advisable to entrust this work to a service center. However, if you have the skills and tools, you can do everything yourself

hex wrench;
slotted screwdriver (flat) 4 and 8 mm;
Phillips screwdriver.

Before disassembling the pump, drain the water from the system or drain a separate area in which the pump is involved, dismantle it and then begin disassembly.

Using a hex wrench or Phillips screwdriver, unscrew 4-6 bolts around the perimeter of the engine housing at the junction with the shell of the pump part.
Remove the shell, leaving the impeller on the rotor shaft along with the engine.
Locate four drainage holes around the perimeter. Using a narrow slotted screwdriver, pry the jacket of the engine compartment under the impeller little by little around the perimeter. As a result, the shaft with the rotor and impeller will come out of the grooves and stator shell. You can help yourself by unscrewing the protective plug on the outside of the pump, inserting a screwdriver into the slot at the end of the shaft and lightly knocking the shaft out of the support bearing.

The analysis is now complete. Now you should clean the surface of the rotor, impeller and the inner surface of the shell from plaque and scale, if any, without damaging the surface of the parts. It is not permissible to use a coarse abrasive. It is better to use a brush with hard polymer bristles. Cleaning products containing a weak solution of hydrochloric acid can help. As a last resort, the finest sandpaper is used - “zero”.

For wet rotor pumps , it is important to check the cleanliness of the channel inside the shaft and the drainage holes located in the protective jacket separating the area of the pump part and the motor. The fluid enters the rotor precisely through these holes and then returns through the internal channel; if they are clogged, engine cooling suffers.

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

The condition of the bearings on which the shaft rests is checked. If they are already quite broken, 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 with new ones if necessary. Once all elements have been cleaned and checked, reassembly is carried out in reverse order.

Circulation pump needs cleaning

Preventive examination

In order for the operation of the circulation pump to be problem-free, it is necessary to regularly check the condition of the equipment. A preventive inspection will help identify negative factors that can lead to serious breakdowns in the future. Their timely elimination will allow you to avoid force majeure situations and complex repair procedures.

A standard inspection includes a few simple steps:

checking the tightness of connections. It is necessary to carefully inspect all fittings with which the pump is attached to the heating system. Some types of connecting elements may become loose over time and must be tightened. In addition, problems may arise with the destruction of the thread or seal - in this case, you need to unscrew the fitting, cut additional turns or wind a new layer of FUM tape, and then reassemble the element;
adding lubricant. There are bearings inside the device that must be well lubricated. Otherwise, they will work worse, which will lead to overheating of the device;
cleaning the filter. The mesh element gradually becomes clogged with dirt, even if you use a very high-quality coolant. Therefore, it is necessary to promptly remove rust and scale particles stuck in the filter.

Actually, this is a basic set of actions that need to be performed for prevention. In addition, you should follow some rules for operating the circulation pump:

Avoid dry running. The pump should only be turned on if the required amount of coolant is present in the heating system. Equipment running “dry” will burn out very quickly, and may even drag down some other electrical appliances;
Avoid prolonged idle time. In many regions, the heating system operates in seasonal mode - from September to May. It is clear that there is no point in launching it in thirty-degree heat. But if left idle for such a long time, some elements of the circulation pump may fail. Therefore, it must be turned on at least once a month for a quarter of an hour. Agree, it takes a little time, but it will help to avoid possible problems in the future;
initially purchase a pump whose characteristics fully correspond to the needs of your heating system. It happens that owners, in an attempt to save money, buy a low-power device and try to use it in a system with a large volume of coolant. As a result, the device constantly works at the limit of its capabilities and, of course, fails very quickly. That is why it is important to make advance calculations of the parameters that you should focus on when purchasing. You can find information on how to do this on our portal;
provide for overheating and “dry running” sensors. These regulators are not available on all models, but it is advisable to find and purchase a device with them. You may not immediately notice the problem on your own. For example, if there is a coolant leak in the system, then until you detect it, the pump will run idle and may simply burn out. And the sensor will react instantly, automatically turning off the equipment, and thereby preventing breakdown.

Ariston dishwashing equipment

If the circulation pump for an Ariston dishwasher is broken, then to disconnect it you will need to lay the equipment on its side, remove the lower part of the bottom, disconnecting the latches. The next step is to disconnect the power cable and remove the broken part along with the fastener. After removal, you need to press your toes with your toes, with which the pump is held in the volute, and turn the part counterclockwise. Ready.

Circulation pump for Ariston dishwasher

In order to install a working central unit in place, you need to do all the previous operations in reverse order:

Insert the device into the cochlea, turning it clockwise until it clicks;
Install the finished structure in the old place and connect the power wire. The control wire also needs to be connected;
The bottom with the pallet must be installed in its original position and the machine must be placed vertically.

Possible causes of problems

If during your next preventive inspection you find that the circulation pump is working “somehow wrong,” then this is a reason to carry out a more in-depth check using some specialized tools. The most common problems are: lack of rotation of the rotor, overheating of the pump and poor coolant current. Each of them may have several reasons. Let's take a closer look at each possible malfunction:

no rotor rotation when the pump is connected to the network. As a rule, this indicates some kind of failure in the delivery of power to the equipment. First of all, you need to inspect all the elements directly responsible for this function: electrical wire, device switch, etc. If you find any defect - for example, even the slightest insulation violation - you must immediately replace the damaged part with a new one. Until the defect is eliminated, the device cannot be used, as this is fraught with short circuits and other troubles. After checking the external elements, inspect the plastic fuse. With frequent voltage drops in the electrical network, it begins to melt and constantly opens the circuit. If you see that it is already openly deformed, it needs to be replaced. The next element that needs to be checked is the winding of the electric motor. To do this, you will need a multimeter, which can be used to measure the resistance level. In normal winding conditions, the indicator can vary from 10 to 15 Ohms or from 35 to 40 Ohms, depending on the specific rotor model. If the multimeter produces infinity or a value close to zero, then this indicates the need to replace the winding;
pump overheating. This usually happens in cases where the circulation equipment for some reason is forced to work under increased load. Detecting overheating is quite simple - if the pump is hotter than the pipe, then this clearly indicates a problem. In the case when this happens with newly installed new equipment, it makes sense to check the correctness of the installation. Incorrect placement of the device may cause it to malfunction. If you find any shortcomings, you need to re-perform the installation procedures, making the appropriate adjustments. Another common cause of overheating is clogging of structural elements with dirt. Rust and scale play a big role in this. They form in some parts of the pipeline, and then fall off piece by piece and go along with the coolant, clogging all the equipment where they fall. This happens with the circulation pump. The presence of foreign particles inside the structure narrows the path along which the coolant flows. Thus, the pump has to apply more force to move the liquid. That's why overheating occurs. The solution to the problem in this case is to clean the clogged elements. The third reason for overheating has already been mentioned above - it may be an insufficient amount of lubricant on the bearings located inside the pump. The fourth reason may be too low - below 220 V - the voltage in the network. You need to check this indicator with a voltmeter and, if problems are found, correct them;
poor coolant current. This refers to situations where the fluid circulates at insufficient speed. The reason for this may be an incorrect connection if your home uses a 380 V network. Check that the electrical wire is connected to the phase correctly - it is quite possible that it needs to be connected to another. The second reason for poor current may be the same clogging of internal structural elements mentioned above. This can be solved by cleaning the elements.

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Moderator: Code

Checking the windings of circulation pumps

Post by Ramiz » 05 Jun 2022, 00:25

Post by VikT » 05 Jun 2022, 01:17

Post by BAXI-Ural » 05 Jun 2022, 10:53

Post by RomanM » June 07, 2022, 21:57

Re: Checking the windings of circulation pumps

Post by Alexey1909 » 05 Sep 2022, 18:55

I have some kind of strange thing that makes my brains, a little, on the ropes. A friend gave me a circulation pump from CXX, model RS 32/8. Power for 3 speeds: 245, 220 and 145 Watt. They gave it to him too and he doesn’t know whether he’s a worker or not.

I plug it in - it doesn’t work, but it barely hums. When the rotor turned, it started working. I thought that the condenser had died (on the case it says 6 microfarads, 1.2 Amperes). I bought a condenser. True, I didn’t find what I needed: I connected 2 condensers of 2 and 4 microfarads in parallel. The one with a nominal value of 2 microfarads was approximately 0.54 Amperes, and the one with a nominal value of 4 – I don’t know, but it was several times healthier and, therefore, I thought that it was probably no less than an Ampere. And, therefore, I figured that with a parallel connection, they would probably withstand 1.2 Amperes. I installed it - it still doesn't work. I thought that the starting winding had burned out. Especially because I noticed that the capacitor that was there was not original - 3 microfarads. I disassembled the engine (I thought that maybe I could rewind it), pulled out the stator, and the winding there was all shiny and there was no burnt mark. I doubted that I had burned out. I should have called right away, but at first I was afraid that there were a lot of contacts coming out of the stator - 6 pieces. Then I realized that I just need to look for pairs between which there is no break, and if at least one contact is without a pair, then this will mean a break. I rang at the terminals to which the wires from the stator are attached. There are 3 pairs: 83, 83, 122 Ohm. It seemed to me that this indicates that the stator is intact. I ring the input (where the power is supplied) at three different speeds: 288, 205, 122 Ohm. Oma. Those. coincides with the first: 205=122+83, 288=122+83+83. It seems that the winding is intact. I don't understand what's wrong. The pump apparently didn’t work much: everything inside was almost clean (there had just been a small leak of rusty water). Why does not it work? I thought that maybe I misunderstood something and the stator burned out after all. But somehow it was not possible to find a technical description on the Internet (it turned out to be a problem to find such a company: the search engine is starting to return porn). And the search by model turned out to be like a ball rolling.

Who knows can say: is the stator normal or could it have burned out?

PS: I am still wildly surprised that ringing the (removable terminal) terminal (removed and ringing) showed that the capacitor is connected in parallel to the network. I couldn’t confuse it: there are 3 contacts for input and one of them is clearly marked as ground. This means that the second two are a network (designated as N and L). And I also can’t imagine how the capacitor could be connected: there are 2 more holes there, and besides connecting the capacitor, I don’t know what else it could be. So the contacts of these two holes are parallel to the network (N and L). And I don’t understand how then some kind of phase shift due to the capacitor could happen here. This also drives me into a stupor. It seems that there is no other way to connect. But, really, when I got the pump, one end of the capacitor was not connected, there was no cover from the box, and only the capacitor, connected by only one wire, was hanging there.

Disassembly of the structure

In some cases, it is not enough to limit yourself to only external work, and you have to get to the internal elements of the structure. It is important to know how to properly disassemble the pump so as not to damage the performance of its parts.

In general, the process is not particularly difficult. The main thing is to stock up on a product called “liquid key”. During long-term use of the device, its elements are tightly glued together by scale, so it is not so easy to separate them. It is undesirable to use ordinary brute force here, since you can damage the part beyond the possibility of subsequent restoration.

Bosch dishwashers

Bosch kitchen helpers are no less popular. So, in favor of this dishwasher, namely its latest versions, we can say the following:

The presence of a large working space, which allows you to load one set of dishes more than in previous versions with identical dimensions.
It is possible to place a separate basket for forks, spoons and other cutlery.
A wide range of different functions, the ability to install more or less intensive washing in the lower section of the dishwasher - this is very convenient, because... You can load dirty dishes, such as pans, into the lower basket.

In most cases, a Bosch model dishwasher recirculation pump is easier to disassemble than to purchase a new one. First you need to remove the pump according to the standard procedure.

Bosch dishwasher circulation pump

Then we move on to disassembling the pump itself:

separate the upper part of the recirculation device by turning it to the right;
the lower element of the spare part is non-separable, so it should be moved to the side;
we find broken plastic bushings on the disassembled part;
the first sleeve is located at the “foot of the mushroom”, and the second is “inside the cap”. Please note that it is quite difficult to select identical bushings, so it is better to contact a mechanic for ceramic substitutes.
Having disassembled the upper part of the mechanism, you need to clean the grease and dirt from its surface. This must be done carefully so as not to damage the part.
at the last stage, you need to return the new bushings to their place and install the top of the pump to the non-separable lower part, which you previously set aside. At this point the repair work is completed.

Design, types and principle of operation of circulation pumps

Without knowing the structure of the circulation pump, you will not only be able to repair such a hydraulic machine if the need arises, but also carry out its regular maintenance. The design of circulation pumps consists of:

body made of stainless steel or non-ferrous alloys;
an electric motor whose shaft is connected to the rotor;
The rotor itself, on which the wheel with blades is installed, is the impeller (its blades, which are in constant contact with the pumped medium, can be made of metal or polymer materials).

Circulation pump design

The circulation pump operates, regardless of its design, according to the following principle.

After applying electric current, the drive motor shaft begins to rotate the rotor on which the impeller is mounted.
The coolant liquid entering the internal part of the pump through the suction pipe is thrown away by the impeller and centrifugal force to the walls of the working chamber.
The liquid, which is affected by centrifugal force, is pushed into the discharge pipe.

As mentioned above, depending on the design features, the heating circulation pump can be of different types. Thus, devices with a rotor are distinguished:

In private homes, “wet” type circulation pumps are most often used.

For circulation pumps of the first type, which are used primarily to equip household heating systems, the rotor is constantly in a liquid medium. This contributes not only to the lubrication of moving elements, but also to their effective cooling. The main advantages of this type of equipment include:

low noise level during operation, since the water in which all the moving elements of such a device are located perfectly absorbs vibrations;
ease of installation (such pumps simply cut into the pipeline), maintenance and repair.

Meanwhile, pumps with a “wet” rotor, if we talk about their disadvantages, are characterized by not very high efficiency, can only be installed in a horizontal position and are very critical of the lack of liquid in the heating system.

Pumps with a dry rotor are installed in separate boiler rooms and are used in systems that heat large areas

The drive motor of pumps with a dry rotor is placed in a separate unit. Rotation from the electric motor shaft is transmitted to the impeller through a special coupling. Unlike devices with a “wet” rotor, pumps of this type are characterized by a higher efficiency (up to 80%), but also a more complex design, which somewhat complicates their maintenance and repair procedures. Circulation pumps with a dry rotor are cut into the pipeline and their housing is attached to the wall, for which a special console is used.

Pumping systems audit

Almost 20% of global electricity consumption comes from pumping systems. From 40% to 60% of the electricity consumed by pumping systems can be saved!

The three main cost items (acquisition, maintenance, electricity) over 10 years of operation are distributed as follows:

85% - energy costs

10% - technical and service maintenance

5% — purchase of equipment

It is the most expensive part of expenses (electricity) that can be significantly reduced! How? We suggest conducting an audit of the pump.

Rules of operation and maintenance

In order not to encounter situations in which the circulation pump installed in the heating system will require repair, it is necessary to strictly follow the operating rules for such equipment, which are as follows.

If there is no water in the pipeline, the circulation pump cannot be started.
The amount of water pressure generated must be within the characteristics specified in the technical data sheet of the circulation pump. If the device produces a reduced or, conversely, increased water pressure, this can lead to its rapid wear and, accordingly, failure.
During the period when the heating system is not in use, the pump must be turned on for circulation at least once a month for a quarter of an hour, which will prevent oxidation and blocking of its moving parts.
It is very important to ensure that the water temperature in the heating system does not exceed 65°. In water heated to a higher temperature, sediment begins to actively fall out, which, interacting with the moving parts of the hydraulic machine, contributes to their active wear and, accordingly, failure of the entire device.

The circulation pump should be inspected and checked for correct operation monthly. Such measures make it possible to identify malfunctions in the operation of equipment at an early stage and promptly take appropriate measures.

Periodic checking of the circulation pump will significantly reduce the likelihood of its failure during the heating season

Correct operation

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 types.
The pump should not be allowed to operate with the water flow stopped, for example, if the valve before or after the pump is closed.
The optimal operating mode should be determined taking into account the maximum and minimum throughput 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 cooled water flows. When a given threshold is exceeded, the process of deposition of hardness salts on the internal surfaces of the pump accelerates many times over.
Long periods of downtime should not be allowed. About once every month or two, it is advisable to turn on the pump for 15 minutes. If this is not done, then the risk of shaft jamming increases during the oxidation process.
It is unacceptable to use a circulation pump to pump dirty water containing dense particles in suspension. A coarse filter must be installed, or the purity of the water or coolant is monitored in other ways.

In operating mode, the pump must have a uniform sound of the operating drive and a constant output pressure value, which is monitored by an installed pressure gauge. If handled well, even the simplest circulation pump can operate for up to 5 years until its main elements wear out.

The most common faults and their elimination

There are several malfunctions that are most typical for circulation pumps, which are quite possible to fix with your own hands. Such malfunctions can be identified by their characteristic symptoms, without even disassembling the pump or using complex diagnostic equipment.

The pump hums when turned on, but the impeller does not rotate

The reason for the situation when the pump is noisy, but the impeller is motionless, is often due to oxidation of the drive motor shaft. This may occur due to the fact that the hydraulic machine has not been used for a long time. To repair a heating pump with your own hands in case of such a malfunction, you must perform the following steps:

turn off the electrical power;
drain all water from the pump and the adjacent pipeline;
Having unscrewed the corresponding screws, remove the drive motor along with the rotor;
resting on the working notch of the rotor with your hand or a screwdriver, forcefully turn it, moving it from its dead point.

Disassembled circulation pump

The pump will make noise, but will not work even if a foreign object has entered its interior and blocks the rotation of the impeller. To repair the circulation pump in such a situation, perform the following steps:

turn off the power supply;
drain water from the pump and adjacent pipeline;
disassemble the pump according to the above scheme;
remove a foreign object;
install a mesh filter on the inlet pipe.

This is what the circulation pump housing looks like from the inside

The pump is turned on and does not hum or work.

If the turned on circulation pump does not make noise, but does not work, there may be problems with the power supply. To identify the cause and eliminate such a malfunction, disassembling the circulation pump may not be necessary: using a tester, check the level and presence of voltage at the terminals of the device. In many cases, to eliminate such a malfunction, it is enough to correctly connect the pump to the power supply.

If there is a fuse in the design of the circulation pump, then it could blow out due to a voltage drop in the electrical network, which could also be the reason why the heating pump does not work and does not make noise when turned on. To restore the pump's operation, simply replace the blown fuse.

Armed with a tester and a circuit diagram, you can find more serious damage to the electrical part of the pump, for example, burnt out windings

After a short period of operation the pump switches off automatically

If a layer of lime deposits has formed on the inner surface of the stator, the running pump will stop periodically. To solve this problem, it is necessary to disassemble the pump and clean all its internal parts from lime deposits.

When turned on, the pump starts to work, but makes a lot of noise.

The reason for the strong noise of the equipment when pumping liquid may be the presence of a large amount of air in the pipeline. To eliminate this problem, it is enough to bleed the air from the pipes. To avoid this in the future, you can install a special unit in the upper part of the heating system circuit that will release air from the pipeline automatically.

Bleeding the pump

Strong vibration of the circulation pump

If the hydraulic machine body vibrates strongly when pumping coolant, this may indicate that the bearing that ensures rotation of the impeller is badly worn. Repairing a heating circulation pump in this case involves replacing a worn bearing.

Grundfos pump graphite end bearing

The circulation pump produces insufficient liquid pressure

Among the reasons for the discrepancy between the liquid pressure and the standard values at the outlet of a centrifugal pump are the following.

The impeller rotates in the wrong direction.
The phase wires in the terminal box are incorrectly connected (with a three-phase connection).
The viscosity of the coolant used is too high.
The filter installed on the suction line is clogged.

The specified problem is eliminated in accordance with the reason that caused its occurrence.

The pump turns off after some time after being turned on

The causes of such a malfunction may be incorrect connection of phase wires in the terminal box, bad or oxidized contacts in the safety unit of the device.

To repair the electronic component of the pump, you will need basic knowledge of electrical engineering.

The pump is heating up

This is another nuisance that occurs quite often when operating such equipment. Why does the circulation pump get hot? The reasons may be different, but this situation always indicates that your equipment is working under increased load.

Thus, many situations in which the circulation pump does not work or does not work correctly can be dealt with independently, without resorting to the services of qualified specialists and without purchasing expensive spare parts and components for repair.

No circulation, heating failure - why

Failure in the heating system, deficiencies, imperfections, all lead to cold radiators. If there is no coolant circulation, then the reason needs to be determined. Most often, the answer to why the heating does not work is on the surface, obvious.

Let's look in order at the main causes of heating malfunctions, why water does not circulate through the pipes, and what needs to be done first.

Let's start with the simplest and most obvious reasons.

It's clogged and clogged.

Every heating system must have a coarse filter. A very small device with a fine mesh and a sump (installed downwards! or at least to the side) saves equipment, pumps, and the boiler from coolant contamination that will be present in any system. Wood shavings, broken threads, rust, water sediment…. everything is retained by the mesh in the filter.

The sedimentation tank must be periodically untwisted and the mesh cleaned.

If the circulation in the heating system of a private house is disrupted, then the first thing you need to do is check the filter, which should be installed on the return line in front of the boiler.

Air in the system, airing

Airing can occur in any closed piping system where air removal measures have not been taken. Air is always present in the coolant, including in a dissolved state, is released during pressure changes, and accumulates at the highest points. Including in the boiler.

Automatic air vents are installed at characteristic, highest points of the system, as well as on collectors and special separators - the normal circuit is equipped with a special air catching device in which air bubbles are released from the coolant.

In addition, Mayevsky valves (manual air vents) should be on each radiator, and also possibly in other elevated places.

Checking the air supply, bleeding the air, installing air vents are common actions if circulation stops and the batteries are cold.

The circulation pump does not work

In private homes, the reason why the heating system stops working is a breakdown of the electrical equipment that controlled the movement of the coolant through the pipes.

If the heating suddenly stops working, then you need to check the functionality of the circulation pump near the solid fuel boiler or the pump in the automated boiler. In addition, the same unit can be installed in each circuit, which must work properly.

Bad polypropylene pipes

Often the consumer (customer) believes that polypropylene pipes are absolutely reliable and cannot cause heating problems or cold radiators.

But polypropylene is much more insidious than old steel or metal-plastic pipelines. Each place of soldering (welding) is a potential increased resistance in the system or a cause of cessation of circulation (weakened movement of water through the batteries), due to deposits of material inside.

It is impossible to control the quality of connections from the outside; all that remains is to cut out pieces, resolder, and remake polypropylene pipes.

Poor performance of a polypropylene system is a real problem for the home installer. Good professionals don’t take on this material at all.

Bad project

It is not uncommon for poor circulation to occur where there is poor design. Typically, the batteries are not connected correctly, according to some sequential circuit, where the last battery in the circuit receives much less coolant.

Another bad design is single-pipe circuits, where it is also difficult to establish the necessary coolant circulation through each battery.

If the radiators do not heat up evenly, or there is poor coolant circulation on individual heating devices, first of all you need to consider how the connection corresponds to the classic circuits - shoulder, associated, radial. It is necessary to bring home heating to normal design standards, and then expect good circulation and uniform heating of the radiators.

Small diameter, overgrown pipes

Old steel pipes become overgrown with rust and deposits from the inside, their throughput capacity decreases significantly over time, and there is only one solution - they need to be replaced with modern ones.

But even during installation, for the sake of economy, mistakes can be made with the choice of pipeline diameter - on mains, on groups of heating devices, diameters of 16 or 20 mm can be installed. The result is noise in the pipes, excessive consumption of electricity, and insufficient coolant flow. What pipe diameters should you choose?

A complex system

A type of bad design is an incorrectly designed complex heating system consisting of many heating circuits and several boilers. Here entire circuits will not work correctly if the work of one affects the neighboring one.

As a rule, one boiler (the backup one does not count) and three circuits - boiler, radiators, heated floors with their pumps are coordinated normally, and no questions arise. But if you connect another working boiler plus a circuit (for example, heating a garage and greenhouse), then the system will become complex. It is difficult to say how the coolant will circulate in it without equalizing the pressures at the connection points.

In complex systems, a competent design is important, installing a hydraulic arrow or an equal pressure ring; more information about the hydraulic separator can be found here

No balancing

Many home heating schemes involve balancing; balancing and control valves are installed in them. For example, between floors, between shoulders, and for each radiator. The taps cover the direction with less hydraulic resistance; accordingly, more coolant will flow to other points.

Children can play with the taps. Or the system is initially unbalanced. Setting up, as a rule, is no problem, you just need to find this tap... How to set up home heating

Neighbors don't provide heat

But complex heating project schemes are of little concern to residents of high-rise buildings, who have a separate riser for each radiator in the apartment. And if any radiator stops heating up normally, it means there is no circulation through the riser, therefore...

How to prepare a circulation pump for the heating season

Before the start of the heating season, in order not to subsequently encounter failure of the circulation pump and its repair, it is necessary to properly prepare the device for a long period of intensive operation.

You should check that the pump is inserted correctly into the pipeline, focusing on the arrow on the body and the impeller rotation indicator. When installing a new pipeline for installing a circulating hydraulic machine, it is better to choose an area immediately in front of the boiler, where the risk of air pockets is minimized.
The gaskets and pipes of the pump must be lubricated to prevent them from drying out.
It is necessary to check the condition of the strainer on the suction pipe and, if it is clogged, clean it thoroughly.
It is also necessary to evaluate the correct connection of the pump to the power supply network, for which a tester is used.
You should check the tightness and reliability of the hydraulic machine connecting units.
You need to perform a test run, the results of which will show whether your equipment is ready for the heating season.

Dishwasher drain and recirculation pumps

Functional differences

The task of the recirculation pump is to pump or pump out water and gas-air mixtures. For a dishwasher, it provides a continuous supply of water into the working chamber, spraying it through special devices for high-quality dishwashing. The water is then filtered, heated and pressurized again - these are the functions of the main engine of the machine.

When choosing a new circulation pump, each user should focus on the following important factors:

real cost;
compatibility with the model of household appliances installed in the house.

The dishwasher pump, which is located at the bottom of the unit, is responsible for draining waste water after all work is completed. On Bosch models it is located next to the circulation pump in one block, on others on top. It differs from the main pump in size, but their operating principle is identical, only the first circulates water inside the machine, and the second removes it into the sewer.

Design

Both pumps have almost the same design, but different dimensions and layout. Let's take a closer look at each detail and the principle of its operation.

Circulation pump

The quality of all modes of the machine depends on the stable operation of this device: water circulation while washing dishes is carried out using a dishwasher pump.

A heating element is inserted into its body - in modern household appliances they are usually of the flow type, i.e. instantaneous.

The circulation pump supplies water to the rocker nozzles, from where it escapes at a fairly high speed; the centrifugal force causes them to rotate and spray the water flow throughout the tank - a working container made of stainless material. All food debris is washed away under this pressure, the water flows to the bottom, where it is filtered, sucked into the tank and again supplied to the nozzles. Thus, there is a constant recirculation of the water flow in the machine.

Drain pump

The drain pump is responsible for removing waste water from the machine after the washing process is completed. The control module gives a signal, the pump turns on and the contaminated water is removed from the machine. Experts call the drain pump impeller a weak point - if it is blocked by a foreign object, it rotates on the shaft, and the device must be replaced: such a defect cannot be repaired.

Diagnosis of failure

Having basic technical knowledge, it is quite possible to independently determine the cause of failure of the dishwasher unit. If there is no water circulation in the machine, the coarse and fine filters are not clogged, and the nozzles on the rocker arms are clean, then this is a sure sign that it is time to replace the circulation motor - there can be no other options.

Important! The circulation motor cannot be repaired, but must be replaced.

When the water in a Bosch dishwasher does not heat up, the circulation pump must also be replaced, because it uses instantaneous elements to heat the water - they are not dismantled.

The most common reason for a drain pump to break down, not only on Bosch machines, but also on other products of a similar type, is the clogging of the drain filter along with the pump with foreign objects. The filter is easy to clean and is ready for use again, but with the pump, things are usually much worse - it needs to be replaced. To dismantle you will have to disassemble almost the entire machine; if you are not confident in your abilities, it is better to call a specialist.

Replacement algorithms

So, in order to replace the recirculation pump for any dishwasher or drain pump, you need to disassemble the machine almost completely. To do this, you will need simple tools: a screwdriver or screwdriver, pliers, an awl and a considerable supply of enthusiasm and self-confidence.

Recommendations for disassembling the circulation pump

Before disassembling the circulation pump, if the need arises (for example, during repairs), you must disconnect it from the power supply and remove it from the pipeline by unscrewing all fastening threaded elements.

After the pump has been removed from the heating system, you can begin to disassemble it:

The cover is removed and secured to the pump body using special bolts.
After removing the cover, the impeller is removed from the inside of the pump.

After this, access to all internal parts of the pump will be provided; they can be inspected, cleaned or replaced with new ones, if necessary.

The sequence of disassembling circulation pumps of various models for repair is demonstrated very well in videos that are easy to find on the Internet.

Reasons for device overheating

The most favorable situation is when the temperature of the coolant in the system coincides with the temperature of the pumping equipment. However, it happens that the pumping apparatus begins to heat up above normal: this is a serious signal that problems have arisen in the operation of the device.

The circulation pump overheats for the following reasons:

Insufficient voltage in the supply network . Because of this, sooner or later the engine will overheat and break down. Therefore, when overheating is detected, the first thing you need to do is check the network parameters: often the problem lies there, and not inside the device.
Poor bearing lubrication . This leads to their rapid erasure, which creates a real threat of rotor jamming. It is best to renew the lubricant in a workshop, because... Complete disassembly of the heating circulation pump will be required.
A foreign object got inside the device, causing it to jam . This item could be a piece of limescale or rust.
System contamination . If the circuit has not been cleaned for many years, its inner walls are usually covered with a thick layer of plaque, which leads to a decrease in the diameter of the tubes. The resistance of the pumped water increases, and the device can no longer cope with the load. To prevent such situations, the system must be periodically cleaned, with the obligatory dismantling of some components (including the pump).
Installation errors . An indication that the pump is installed incorrectly is if it overheats from the very beginning of operation. Equipment of this type is a complex device, since only specialists can check the heating pump for correct connection.

Modern models of heating circulation pumps are practical and easy-to-use devices. They are characterized by a high degree of reliability, which allows, with proper installation, practically no subsequent maintenance. After detecting overheating or other malfunctions, you should carefully measure your strength before repairing the heating circulation pump yourself. Sometimes it happens that eliminating damage caused by unprofessional disassembly of a mechanism is more expensive than repairing the original defect.