Circulation pumps are installed in heating systems with forced or natural circulation. It is needed to increase heat transfer and to be able to regulate the temperature in the room. Installing a circulation pump is not the most difficult task; if you have a minimum of skills, you can do it yourself, with your own hands.
What is a circulation pump and why is it needed?
A circulation pump is a device that changes the speed of movement of a liquid medium without changing pressure. In heating systems it is installed for more efficient heating. In systems with forced circulation it is a mandatory element, in gravity systems it can be installed if it is necessary to increase the thermal power. Installing a circulation pump with several speeds makes it possible to change the amount of heat transferred depending on the outside temperature, thus maintaining a stable temperature in the room.
Cross-section of a circulation pump with a wet rotor
There are two types of such units - with a dry and wet rotor. Devices with a dry rotor have a high efficiency (about 80%), but are very noisy and require regular maintenance. Units with a wet rotor operate almost silently; with normal coolant quality, they can pump water without failure for more than 10 years. They have a lower efficiency (about 50%), but their characteristics are more than sufficient for heating any private home.
Where to put
It is recommended to install a circulation pump after the boiler, before the first branch, but on the supply or return pipeline it doesn’t matter. Modern units are made from materials that can withstand temperatures up to 100-115°C. There are few heating systems that work with a hotter coolant, so considerations of a more “comfortable” temperature are untenable, but if you feel safer, put it in the return line.
There is no difference in hydraulics - the boiler, and the rest of the system; it makes absolutely no difference whether there is a pump in the supply or return branch. What matters is the correct installation, in the sense of strapping, and the correct orientation of the rotor in space. Nothing else matters.
There is one important point regarding the installation location. If the heating system has two separate branches - on the right and left wings of the house or on the first and second floor - it makes sense to install a separate unit on each, and not one common one - directly after the boiler. Moreover, the same rule remains on these branches: immediately after the boiler, before the first branch in this heating circuit. This will make it possible to set the required thermal conditions in each part of the house independently of the other, and also in two-story houses to save on heating. How? Due to the fact that the second floor is usually much warmer than the first floor and much less heat is required there. If there are two pumps in the branch that goes up, the speed of movement of the coolant is set much lower, and this allows you to burn less fuel, without compromising the comfort of living.
Harness
There are two types of heating systems - forced and natural circulation. Systems with forced circulation cannot work without a pump; systems with natural circulation work, but in this mode they have lower heat transfer. However, less heat is still much better than no heat at all, so in areas where electricity is often cut off, the system is designed as hydraulic (with natural circulation), and then a pump is installed into it. This gives high heating efficiency and reliability. It is clear that the installation of a circulation pump in these systems is different.
All heating systems with heated floors are forced - without a pump, the coolant will not pass through such large circuits
Forced circulation
Since a forced circulation heating system without a pump is inoperative, it is installed directly into the gap in the supply or return pipe (of your choice).
Most problems with the circulation pump arise due to the presence of mechanical impurities (sand, other abrasive particles) in the coolant. They can jam the impeller and stop the motor. Therefore, a mesh dirt filter must be placed in front of the unit.
Installing a circulation pump in a forced circulation system
It is also advisable to install ball valves on both sides. They will make it possible to replace or repair the device without draining the coolant from the system. Turn off the taps and remove the unit. Only that part of the water that was directly in this piece of the system is drained.
Natural circulation
The piping of the circulation pump in gravity systems has one significant difference - a bypass is required. This is a jumper that makes the system operational when the pump is not working. One ball shut-off valve is installed on the bypass, which is closed the entire time the pumping is running. In this mode, the system operates as forced.
When the electricity goes out or the unit fails, the valve on the jumper is opened, the valve leading to the pump is closed, and the system operates as a gravity system.
Installation features
There is one important point, without which the installation of the circulation pump will require rework: it is necessary to rotate the rotor so that it is directed horizontally. The second point is the direction of flow. There is an arrow on the body indicating which direction the coolant should flow. This is how you turn the unit so that the direction of movement of the coolant is “in the direction of the arrow”.
The pump itself can be installed both horizontally and vertically, just when selecting a model, make sure that it can work in both positions. And one more point: with a vertical arrangement, the power (pressure created) drops by about 30%. This must be taken into account when choosing a model.
Power connection
The circulation pumps operate from a 220 V network. The connection is standard; a separate power supply line with a circuit breaker is desirable. The connection requires three wires - phase, neutral and ground.
The connection to the network itself can be organized using a three-pin socket and plug. This connection method is used if the pump comes with a connected power wire. It can also be connected via a terminal block or directly with a cable to the terminals.
The terminals are located under a plastic cover. We remove it by unscrewing several bolts and find three connectors. They are usually labeled (the pictograms are N - neutral wire, L - phase, and “ground” has an international designation), so it’s hard to make a mistake.
Since the entire system depends on the performance of the circulation pump, it makes sense to make a backup power supply - install a stabilizer with connected batteries. With such a power supply system, everything will work for several days, since the pump itself and the boiler automation “pulls” electricity to a maximum of 250-300 W. But when organizing, you need to calculate everything and select the battery capacity. The disadvantage of such a system is the need to ensure that the batteries do not discharge.
With the onset of winter cold, many motorists are seriously thinking about insulating their car. VAZ family cars are most susceptible to this problem. Their standard heaters do not heat well enough, this is especially noticeable at idle. This problem can be resolved by installing an additional pump. In addition, the interior is insulated through other modifications, for example, by modifying the heater to increase the efficiency of hot air flow from the sides and along the passengers' legs, or by installing an additional heater. In this article we will talk about how to modify the car’s cooling system by installing an additional pump in the cut pipe. For some car owners, finalizing such a plan may be a waste of time, but as an example, we note that such implementations are already successfully used at the factory level by such European automotive giants as Mercedes and BMW.
What additional pumps are there?
As a rule, two different types of pumps are purchased:
A pump for a Gazelle costs an average of 300-500 hryvnia.
Bosch pump, which is three times more expensive than the domestic one, depending on the pump power.
Due to its poor design, the Gazelle begins to leak through the gasket after some time. This problem can be solved by first disassembling the pump and lubricating the gasket with silicone sealant, or by tightly fixing the cover with the gasket with thermal glue or other sealant. The German pump does not have such a drawback due to its design. There are no gaskets and no leaks can occur.
Purpose of an additional pump
Let's imagine that it is 10 degrees below zero outside, and the engine has warmed up to 85 degrees. Now turn off the engine and turn on the heater at first speed. Warm air will blow into the cabin almost immediately, but the flow will be too weak. But as soon as you start the additional pump, hot air will immediately blow in, and its flow will not stop until the temperature of the power unit drops to a temperature of 45 degrees.
We are not pioneers. Additional pumps have been installed on many car models for quite a long time, the responsible owners of which are “at war” with the problems of poor heater performance in the cold season. With this solution, replacing the heater radiator is not required at all, especially since this procedure is a very labor-intensive task. On some cars, you will have to remove the entire front panel of the interior.
Tuning a car heating system involves installing an additional electric pump. We will consider this procedure using the example of the VAZ-2110, because it is the owners of these cars who complain that the interior does not heat up well enough, especially when the power unit is idling. To carry out tuning you will need:
1. An electric pump from a Gazelle is precisely this option that is best suited for the role of additionally pumping warm air into the car’s interior. Structurally, this is a conventional centrifugal pump in which the coolant flow is rejected from the center to the periphery using blades.
2. Relay from starter or ignition. In such elements the contacts are best kept open.
3. Short lengths of aluminum and reinforced hoses.
4. Three liters of coolant.
5. Six clamps of the required diameter.
Before starting work, it is necessary to allow the engine to cool naturally. Then drain the coolant into a clean container. You will need it later, so make sure it remains clean.
After this, take the new pump and unscrew the four screws from the side where the impeller is located. Lubricate the rubber gasket with conventional sealant. Next, reassemble the pump in the reverse order, but instead of unscrewing screws, install long thin bolts under the nuts. This is the only way to ensure the best sealing of the connection. At the next stage, you need to determine the installation location of the additional electric pump. There are several options for this:
- on a pin near the battery;
On the washer reservoir mounting stud;
On the mounts there is standard sound insulation, which is located on the engine panel.
As a rule, they follow the standard approach, which is described in the instructions that come with the electric pump, that is, option number two from our list. The pump must be placed in such a way that its horizontal pipe is directed towards the block, for which the metal mounting clamp must be loosened. Next, having installed the pump in the proper position, you need to install the hoses. To do this, they need to be removed from the heater and from the tube coming out from under the manifold. Next, take a reinforced hose of sufficient length and try it on in place. The main thing is that it runs without kinks or stresses from the brass manifold tube to the pump tube.
It is necessary to install an adapter angle to prevent bending, with a small piece of hose of at least 10 cm. The structure is secured with four clamps.
It is much easier to connect the pump and the hose from the stove to each other, since there is no need to install adapters, you just need to stretch the required size hose and connect it, also securing it with the two remaining clamps. In order to secure everything “properly”, it is better to put an aluminum corrugated pipe on the mounted hoses in the area of the exhaust manifold so that the hoses do not melt from the hot air. Finally secure everything and start connecting the electrical connections.
When installing the pump, the ground wire of the winding must be connected to ground. Connect the relay power wire to the pump wiring. Pass the positive one coming from the relay through a fuse connected to the positive terminal of the battery. Stretch the control plus from the relay to the start button directly into the interior along with the battery plus. You can place the button in any place convenient for you.
At the final stage, all that remains is to check the pump in action. Return the coolant to its place, start the power unit and wait a little until it warms up. Then use the displayed button to start the additional pump.
Installation and connection of an additional electric pump to the car cooling system
If the heater in your beloved car is not as hot as your love for it, then I advise you to install an additional electric pump in the cooling system. I have carried out this procedure in practice and although it is far from negative on the street, the work of the additional pump is still assessed as significantly improving the operation of the car heater.
A rather long path has been covered regarding the need to install an additional pump, as a result of which a lot of other work has been done, and the theoretical essence of installing an additional pump has also been analyzed, an article about which you can read Here .
So, to install and connect an additional pump you will need:
- The pump itself. The choice fell on the BOSCH pump (number 0 392 020 024). Small, quiet, productive, RELIABLE, with a lot of positive reviews, it was purchased for 1,500 rubles in an online store. I refused the Gazelle electric pump due to negative reviews, because... she's unreliable.
We embed the LED and button into a free plug on the panel.
We place an electronic thermostat on a PIC microcontroller under the glove compartment. We connect it to the heater fan motor connector.
I built the temperature sensor into the panel where the heater damper controls are located. There was even a special place for such sensors (a square lattice window 1x1cm), apparently for more sophisticated models (those with climate control).
From the passenger compartment to the engine compartment, through a bundle of standard wires, we stretch the control wire.
We place a relay and a fuse in the engine compartment. Because The block under the relay is equipped with a protective diode, then when connecting, we must observe the polarity, otherwise the diode will emit the magic smoke on which it should work :-). We make all the wires in double insulation (we wrap electrical tape on top of the regular wire). The fuse should be placed as close as possible to the point where the wire connects to the power supply. In my photo, the fuse is taped to the relay with electrical tape, but the wire itself is connected to the power wire of the junction box, which in turn is protected by a standard fuse. So my wire is not connected directly to the battery, as it may seem in the photo, but through a fuse in the junction box.
The pump itself is installed in the gap in the stove pipe. In this case, it is necessary to orient the direction of movement of the coolant (coolant) in the pump (marked with an arrow on the pump body) with the direction of movement of the coolant in the pipes. You can check the direction of the coolant flow by disconnecting one of the pipes from the heater and briefly starting the engine. In general, from which hole it leaks, it presses from there. There will not be time to pour out a lot of coolant, but you will still need to buy additional coolant to top it up.
Now, knowing where the “direct” is and where the “return” is and aligning it with the pump arrow, you can figure out a convenient place to mount the pump. The pump can be connected to a gap in both the supply and return pipes, as long as it is convenient, not forgetting to align it with the direction of movement of the coolant in the pump. The easiest way for me was to install a pump onto the supply pipe.
The diameter of the pump fittings is designed to connect 20mm pipes, while the stove pipes are 18mm. I solved the problem by lubricating the pump fittings with Litol. On the second attempt the pipes were tensioned. For extra confidence, the connections are tightened with screw clamps.
You will have to think a little about the pump mounting. With the help of one corner and a curved straight hanger, I got it like this:
We connect the pump, observing the polarity, to the relay using speaker terminals.
We put everything that we removed in place (the box for the air filter with pipes), add coolant and start the engine for testing.
The very first testing, even without the use of precision instruments, shows a significant increase in stove performance. In general, we are waiting for the harsh Far Eastern winter and the wife’s verdict.
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To make heated water flow more cheerfully through the pipes, a circulation pump is installed in the heating systems of private houses. This solution provides tangible benefits. But the main question that concerns homeowners and is covered in this material is where it is better to install the pump and how to install it correctly. After all, the main part of the controversy and doubt is caused by the place where the unit is inserted. And at the same time, we’ll figure out how to connect it to the house electrical network with our own hands.
What are the benefits of pump heating systems?
30 years ago, so-called steam heating was common in private homes, where the coolant circulated through pipes and radiators by gravity, and the heat source was a gas boiler or wood stove. Pumps for pumping water were used in district heating networks. When compact circulation pumps for heating appeared, they migrated to private housing construction, as they provided the following advantages:
- The speed of coolant movement has increased. The heat generated by the boiler has become faster delivered to the radiators and transferred to the premises.
- Accordingly, the process of heating the house has accelerated significantly.
- The higher the flow rate, the greater the pipe capacity. This means that the same amount of heat can be delivered to rooms through lines of smaller diameter. Simply put, the pipelines have become half the size thanks to the forced circulation of water from the pump, which is cheaper and more practical.
- Highways can now be laid with a minimum slope and water heating circuits can be made as complex and extensive as desired. The main thing is the correct selection of the pumping unit in terms of power and pressure created.
- The household circulation pump for heating has made it possible to organize underfloor heating and more efficient closed systems operating under pressure.
- It was possible to remove from view the ubiquitous pipes that run through the rooms and do not always harmonize with the interior. Increasingly, heating communications are laid in walls, under floor coverings and behind suspended (suspended) ceilings.
Note. A minimum slope of 2-3 mm per 1 m of pipeline is needed to empty the network in case of repair or maintenance. Previously, it was made at least 5 mm / 1 m.p.
Pumping systems also have disadvantages. This is a dependence on electricity and its consumption by the pumping unit during the heating season. Therefore, if there are frequent power outages, the circulation pump must be installed together with an uninterruptible power supply unit or connected to an electric generator. The second drawback is not critical; if you select the power of the device correctly, then the electricity consumption will be acceptable.
Leading manufacturers of heating equipment, such as Grundfos or Wilo, have developed new models of units that can save energy. For example, if you buy and install an Alpfa2 circulation pump from the Grundfos brand, it will automatically change its performance depending on the needs of the heating system. True, its price starts from 120 USD. e.
New generation circulation units from Grundfos – models Alpfa2 and Alpfa2L Where to install the pump - supply or return
Despite the abundance of information on the Internet, it is quite difficult for the user to understand how to correctly install a heating pump in order to ensure forced circulation of water in the system of their own home. The reason is the inconsistency of this information, which causes constant debate on thematic forums. Most of the so-called specialists claim that the unit is installed only on the return pipeline, citing the following conclusions:
- the coolant temperature in the supply is much higher than in the return, so the pump will not last long;
- The density of hot water in the supply line is less, so it is more difficult to pump;
- The static pressure in the return line is higher, which makes the pump easier to operate.
Interesting fact. Sometimes a person accidentally ends up in a boiler room that provides central heating for apartments, and sees the units there embedded in the return line. After this, he considers this solution to be the only correct one, although he does not know that in other boiler houses centrifugal pumps can also be installed on the supply pipe.
We respond to the above statements point by point:
- Household circulation pumps are designed for a maximum coolant temperature of 110 °C. In a home heating network it rarely rises above 70 degrees, and the boiler will not heat the water more than 90 °C.
- The density of water at 50 degrees is 988 kg/m³, and at 70 °C – 977.8 kg/m³. For a unit that develops a pressure of 4-6 m of water column and is capable of pumping about a ton of coolant in 1 hour, the difference in the density of the transported medium is 10 kg/m³ (the volume of a ten-liter canister) is simply negligible.
- In practice, the difference in static pressure of the coolant in the supply and return lines is equally insignificant.
This is a simple conclusion: Circulation pumps for heating can be embedded into both the return and supply pipelines of the heating system of a private house. This factor will not in any way affect the performance of the unit or the heating efficiency of the building.
Boiler room made by our expert Vladimir Sukhorukov. There is convenient access to all equipment, including pumps. The exception is cheap solid fuel direct combustion boilers that are not equipped with automation. When overheated, the coolant in them boils, since burning wood cannot be extinguished at once. If the circulation pump is installed on the supply side, then the resulting steam mixed with water enters the housing with the impeller. The further process looks like this:
- The impeller of the pumping device is not designed to move gases. Therefore, the performance of the device decreases sharply, and the flow rate of the coolant drops.
- Less cooling water enters the boiler tank, causing overheating to increase and even more steam to be produced.
- An increase in the amount of steam and its entry into the impeller leads to a complete stop of the coolant movement in the system. An emergency situation occurs and, as a result of an increase in pressure, a safety valve is activated, releasing steam directly into the boiler room.
- If no measures are taken to extinguish the firewood, the valve cannot cope with the pressure release and an explosion occurs with the destruction of the boiler shell.
For reference. In cheap heat generators made of thin metal, the response threshold of the safety valve is 2 Bar. In higher quality TT boilers, this threshold is set at 3 Bar.
Practice shows that no more than 5 minutes pass from the start of the overheating process to the valve activation. If you install a circulation pump on the return pipe, then steam will not enter it and the time period before an accident will increase to 20 minutes. That is, installing the unit on the return line will not prevent an explosion, but will delay it, which will give more time to fix the problem. Hence the recommendation: it is better to install pumps for boilers running on wood and coal on the return pipeline.
For well-automated pellet heaters, the installation location does not matter. You will learn more information on the topic from our expert’s video:
Installation diagrams in various types of systems
To begin with, let’s clarify the place where to install the flow pump, which circulates water through the boiler and forcibly directs it to the radiators of the heating system. According to ours, whose experience is trustworthy, the installation location must be chosen in such a way that the unit is convenient to maintain. On the supply side it should be located after the safety group and shut-off valves, as shown in the installation diagram:
In order for the unit to be removed and serviced, shut-off valves must be installed on the sides On the return, the pump must be placed directly in front of the heat generator, and in tandem with a filter - a mud trap, so that you do not have to buy and install extra taps. The wiring diagram for the pumping unit looks like this:
When installing on the return line, it is better to place the mud collector in front of the pump unit Recommendation. A circulation pump can be installed in this way in both a closed and an open heating system, there is not much difference. The statement also applies to the collector system, where the coolant moves to the radiators through separate connections connected to the distribution comb.
A separate issue is an open heating system with a circulation pump, capable of operating in 2 modes - forced and gravity. The latter is useful for homes where power outages often occur, and the owners’ income does not allow them to buy an uninterruptible power supply unit or a generator. Then the device with shut-off valves must be installed on the bypass, and a tap must be inserted into a straight line, as shown in the diagram:
This scheme can operate in forced and gravity mode Important point. On sale there are ready-made bypass units with a pump, where instead of a tap on the flow there is a check valve. Such a solution cannot be called correct, since a spring-type check valve creates a resistance of the order of 0.08-0.1 Bar, which is too much for a gravity heating system. Instead, you can use a petal valve, but it must be installed only in a horizontal position.
Finally, we will explain how to install and connect a circulation pump to a boiler that burns solid fuel. As mentioned above, it is better to place the unit on the line coming from the heating system to the heat generator, as shown in the diagram:
Installation rules
The design of a household circulation pump from any manufacturer provides for its fastening to pipelines or shut-off valves using union nuts (American). This allows it to be quickly dismantled if necessary, for example, for replacement or repair. When installing the pump unit, follow these recommendations:
- Place the device on any sections of pipelines - horizontal, vertical or inclined, but with one condition: the rotor axis must be in a horizontal position. That is, installation “head down” or up is unacceptable.
- Please note that the plastic box with electrical contacts is located on top of the case, otherwise it will be flooded with water in the event of an accident. Yes, and servicing the product will not be easy. This is easy to achieve: unscrew the screws securing the casing and turn it to the desired angle.
- Remember to follow the flow direction indicated by the arrow on the housing.
- So that the product can be removed without emptying the system, install shut-off valves before and after it, as shown in the diagrams in the previous section.
A visual aid showing what position the pump unit should be in Advice. It so happened that the load from the weight of the circulation unit will fall on 1 or 2 ball valves (depending on the orientation of the area in space). Hence the recommendation: do not save money and buy high-quality shut-off valves, whose body will not crack over time from mechanical stress.
About installing additional units
As a rule, in a closed or open radiator heating system, where the heat source is a single boiler, it is enough to install one circulation pump. In more complex schemes, additional units are used for pumping water (there may be 2 or more of them). They are placed in the following cases:
- when more than one boiler installation is used to heat a private house;
- if a buffer tank is involved in the piping scheme;
- the heating system has several branches serving various consumers - radiators, heated floors and an indirect heating boiler;
- the same, using a hydraulic separator (hydraulic arrow);
- for organizing water circulation in underfloor heating circuits.
Correct wiring of several boilers operating on different types of fuel requires that each of them have its own pumping unit, as shown in the diagram for the joint connection of an electric and TT boiler. , described in our other article.
Connecting an electric and TT boiler with two pumping devices In a circuit with a buffer tank, it is necessary to install an additional pump, because it involves at least 2 circulation circuits - boiler and heating.
The buffer tank divides the system into 2 circuits, although in practice there are more of them A separate story is a complex heating scheme with several branches, implemented in large cottages with 2-4 floors. Here, from 3 to 8 pumping devices can be used (sometimes more), supplying coolant floor by floor and to different heating devices. An example of such a circuit is shown below.
Finally, a second circulation pump is installed when heating the house with water-heated floors. Together with the mixing unit, it performs the task of preparing coolant with a temperature of 35-45 ° C. is clearly described in a separate material.
This pumping unit forces coolant to circulate through the heating circuits of underfloor heating. Reminder. Sometimes pumping devices do not need to be installed for heating at all. The fact is that most electric and gas wall-mounted heat generators are equipped with their own pumping units built inside the housing.
Connecting the circulation pump to the electrical network
There are several ways to connect power to the device:
- through a conventional differential machine;
- with thermostat control;
- connection to the network together with an uninterruptible power supply unit (UPS);
- powering the unit from the boiler automation.
Warning. Often, homeowners simply plug the pump into a regular outlet, connecting the wires to a purchased plug. We cannot recommend this approach, because connection without grounding and a safety circuit breaker is dangerous. If there is a problem with the device or if it is filled with water, you risk receiving an electric shock.
Typical connection diagram with differential circuit breaker The first connection diagram is quite simple and any user can assemble it with his own hands. You will need an 8 A differential circuit breaker, wires and contacts. Connect to grounding both in this circuit and in all others.
To automatically stop the movement of the coolant when cooling to a certain temperature, an electrical circuit is used to connect a circulation pump with a thermostat. The latter is attached to the supply pipeline and breaks the power supply circuit when the water temperature drops below a set value.
Connecting a phase wire to the pump through an overhead thermostat Attention! To ensure that the thermostat does not lie and turns off the circulation in time, it must be attached to a metal section of the line. Polymers do not transfer heat well, so when mounted on a plastic pipe, the device will not work correctly.
There are no difficulties in connecting the power supply through a UPS, for which the latter has special connectors. The heat generator itself should also be connected to them if it needs electricity. But connecting the pump to the boiler control panel or to its automation is a more complicated procedure. It is advisable to have knowledge and skills in the field of electrical engineering.
The boiler is also connected to the uninterruptible unit if it needs electricity At what speed should the pump in the heating system operate?
The purpose of forced circulation is to effectively heat the house through the reliable delivery of heat to all consumers of the system, right up to the furthest radiator. To do this, the pumping unit must develop the required pressure (otherwise known as pressure), which is ideally calculated by design engineers based on the hydraulic resistance of the pipeline network.
Most household pumps have from 3 to 7 rotor speeds, due to which the performance and pressure generated can be increased or decreased. In order not to torment you with hydraulic calculations, we offer the following method for selecting the optimal speed:
- Find a laser surface thermometer (pyrometer). Put the heating system into operating mode.
- Measure the surface temperature of the pipe at the inlet and outlet of the boiler.
- If the temperature difference is more than 20 °C, increase the rotor speed. After 30 minutes, repeat the measurement.
- When the temperature difference is less than 10 °C, the water flow rate must be reduced. The goal is to achieve a delta between supply and return of about 15 °C.
The minimum number of rotor speeds is 3, but sometimes 7 or more Advice. Do not switch the pump to a different circulation speed “on the fly”. Disconnect it from the network, move the regulator to a different position, and then put it back into operation.
You can do without a pyrometer when thermometers are installed on the supply and return lines. If the adjustment limits do not allow you to enter the range of 10-20 °C temperature difference, your system is not working efficiently due to an incorrectly selected circulation pump. Too cold return water increases the load on the boiler and increases fuel consumption. Water that is too hot means that it flows too quickly and does not have time to transfer heat to the heating devices.
The leading European brand Grundfos offers the latest generation Alpfa3 circulation pumps, which can independently select performance depending on the load and thus adapt the work to changing conditions. With their help, you can even balance the heating system, which our expert will tell you about in the next video:
Conclusion
Now you know how to properly install a circulation pump in a water heating system and connect it to the power supply of a country house. This will save you from making all sorts of mistakes that lead to minor and major troubles. Again, you can install and wire the unit yourself. The only difficulty is to embed it into a section of steel pipeline. But there is a way out: find a set of tools for manually cutting pipe threads, cut out a piece of pipe with a grinder and mount the pump unit.
Water heating is a fairly common option for arranging private homes. Firstly, this type of heating is economically beneficial both in terms of installation and operation, and secondly, its installation is a fairly simple and not labor-intensive process. One of the main components of the thermal circuit is the pump for the heating boiler, which creates artificial pressure in the system, “forcing” the coolant to constantly circulate through the circuit. You will learn how a boiler pump works in this article.
Purpose of centrifugal pumps
Heating systems with natural coolant circulation were popular several decades ago. Today, such designs are quite rare. The principle of operation is simple: due to the difference in density of hot and cold water, liquid moves through the main line and radiators. In addition, to improve water circulation along the circuit, a slight slope of the pipeline is required.
However, such systems are not ideal and even minor errors during installation can lead to a decrease in the efficiency of the heating unit as a whole. Thus, in the last few years, people have increasingly begun to equip heating lines with centrifugal hydraulic pump units, which easily eliminate all the shortcomings of blocks with natural movement of hot water through the pipeline.
Among the main advantages of an additional pump it is worth highlighting:
- there is no need to slope the pipes to improve the movement of the coolant along the circuit;
- no restrictions on consumables, namely on the diametrical size of pipes (for natural circulation, large cross-section pipes are recommended to increase throughput);
- Due to temperature changes, air pockets are not created in the heating main, which prevent full circulation of the liquid;
- ensuring uniform heating of the room, since hot water moves at a certain, always the same speed;
- Due to the high speed of movement of the coolant, the temperature difference at the outlet and inlet of the boiler is minimal, which does not require large fuel consumption to warm it up.
In addition, a stably maintained temperature regime allows not only to save on thermal resources, but also significantly extends the operating life of the heating boiler.
VIDEO: Do-it-yourself installation and installation of a circulation pump for heating with automation
Types of pumping units
So, we have already figured out what a circulation pump is for. And the name of the device itself answers this question. Let's go further. The correct functioning of this unit is ensured by a special element - a rotor, the ends of which are equipped with blades. Through the latter, hot water is forced to move (namely, in most cases it acts as a coolant) along the main line.
Most modern models, such as, for example, a 12-watt heating circulation pump, are equipped with one hydraulic rotor. However, manufacturers also build two such elements into some devices. Here we are talking about very powerful units that are used for industrial purposes, but not for domestic purposes.
Regardless of the number of rotor units, pumps for heating boilers will function effectively only if the thermal circuit does not contain air masses inside.
Currently, manufacturers of such functional equipment can offer potential buyers two options for devices:
- with wet rotor;
- with dry rotor.
And to understand how these two types differ, let’s talk in more detail about each of them.
Read with this article: Circulation pump for heating
With wet rotor
This type of blower is characterized by complete immersion of the rotor assembly in the heat source, that is, in water. A pump with a wet rotor is assembled according to a special design, and its design allows the moving liquid to come into contact with the blades, thereby ensuring lubrication and cooling of the components of this device.
The clear advantage of such devices is that such a circulation pump for the boiler operates very quietly, which cannot be said about the second model with a dry hydraulic rotor. This is due to the fact that vibration and sound waves of a functioning rotor unit are completely absorbed by the liquid itself.
Mini water pumps of identical functionality and configuration can be used both as the main device (if the heated room has a small area) and in addition to the domestic hot water supply. In addition, such household hydraulic pumps are suitable for heating a private home, and they can also be used for industrial purposes. True, then you need to pay attention to the power of the device, since household appliances are not able to ensure full circulation of the coolant along a long circuit.
With dry rotor
This option involves complete isolation of all components of the pumping apparatus from the liquid, which ensures higher power than the previous model. And this, in turn, makes it possible to pump fairly large volumes of coolant, which leads to the use of such devices to create a thermal circuit in rooms with a large area.
If we compare the two options, the obvious difference between this type is that in addition to the location of the functioning elements relative to the liquid, in hydraulic pumps with a dry rotor it is possible to replace the engine with a more powerful one, which makes it universal. But at the same time, vibrations and sound waves will be heard clearly, so it is better to place such devices in separate boiler rooms.
Installation location in the general system
The connection of the pump to the heating system, as a rule, is carried out on the “return”, that is, in the place where the cooled coolant returns to the heating boiler for further heating. However, modern models can easily be placed in any other place, regardless of the location of the boiler.
It is very important that the connection diagram for the heating circulation pump that is chosen as the main one allows access to the equipment. Each element of the system needs preventive maintenance and regular maintenance, so a free approach is very necessary.
Read with this article: Calculation of a circulation pump for the heating system of a private house
For the installation to work effectively, you must adhere to several rules:
- The placement of the expansion tank should be at least 80 cm above the level of the extreme point of the thermal circuit. If your system does not have a pumping unit, and water circulates through the main line by natural movement, then the expansion tank is installed in the attic. Also, this device can be mounted at the highest location of the pipeline and radiators.
- The heating unit is equipped with a bypass to bypass the forced circulation system. This is relevant if the pumping device malfunctions or if there are problems with the power supply.
To prevent the accumulation of air masses in the heating main, a Mayevsky valve or special automatic valves should be installed in the bypass or the highest points of the heating circuit to release excess air.
You can buy a pump for a heating boiler in any specialized store; it is only important to choose the right one in terms of power, with which sales consultants can help. By giving preference to centrifugal pumping devices, you equip your heating system with a unit that will provide comfortable temperature living conditions in your home. And lastly, be sure to issue a guarantee. Any complex equipment, including a circulation pump, can fail for objective reasons and without the fault of the consumer.
VIDEO: Circulation pump for heating with automation to aid natural circulation
www.portaltepla.ru
Installation of a pump in a heating system
- 1 Select pump parameters
- 2 Pump insert
- 3 Installation benefits
Heating system pump
The circulation pump is designed for forced circulation of water in the heating system. Its installation in a heating system is carried out not only in cases where the system operates with natural circulation of water due to its heating and the slope of the pipes, but also as an auxiliary one, when the main one, built into the heating boiler, is not able to provide the required pressure for water circulation.
The circulation device can be installed on heating systems whose boilers operate on any type of fuel. That is, coal, wood, diesel, fuel oil, gas and electricity.
Selecting pump parameters
Pump parameters
In order to install a circulation device in a heating system, it is necessary to take into account its parameters. The main parameters are:
- Pressure is the ability of the unit to raise water to a certain height. Measured in meters, symbol H;
- Flow is the ability to pump a certain amount of liquid over a certain period of time. Measured in cubic meters (m3/hour), symbol Q.
Considering that circulation pumps are generally not designed to lift water, but only to circulate, the main focus when purchasing it will be on the letter Q. If you have a house with several floors, then the main condition for raising water to the top will not be pressure, and the lack of air in the system and, as a consequence, normal water circulation, which will ensure this rise.
Calculation. In order to determine the required flow rate (Q), you can use the formula Q=N/(t2-t1).
- Q – flow rate (m3/hour);
- N – boiler or geyser power (kW);
- t1 – water temperature at the outlet of the return pipeline (°C);
- t2 is the water temperature at the outlet of the boiler or supply column (°C).
But these calculations are valid only in cases where the boiler does not have a circulation device. Nowadays boilers are mainly produced with a built-in circulation pump. When purchasing a new modern boiler, you will not have the need to purchase an additional device.
But what if the boiler was installed a long time ago, and the heating system had to be enlarged due to a new extension, or, at worst, you simply made a mistake in the calculations when buying a new boiler? In this case, installing an additional pump becomes an absolute necessity.
Pump insert
Connection to the heating system
Should the pump be embedded in the water supply pipe or should it be located on the return pipe of the pipeline? Opinions vary. It is interesting that although everyone defends their point of view, nevertheless, pumps installed in any of the heating directions behave excellently. So, although the author of this article is accustomed to using a “return” to mount the device, he will not insist on this as the only correct solution.
I would like to draw your attention to the installation method itself. It does not matter what material the heating system is made of. Whether it is metal or eco-plastic, it is best to insert the device not directly into the pipe, but by going around it. For metal pipes, a ready-made assembly for bypassing the main line is sold.
The point is this: another pipe in the form of a wide letter P, with a pump mounted in the middle, is welded or soldered to the side of the main heating pipe. Cranes are installed on both sides of it, which will serve two purposes:
- by turning off one of the taps, we restore the natural circulation of water in the heating;
- By turning off both taps, we can replace (repair) the circulation system without draining the water.
When inserting, pay attention to the direction of water movement. It is usually marked with an arrow on the body of the unit.
When connecting to the mains in systems with natural circulation, use an automatic fuse with a flag. It will serve two purposes at the same time - both as a fuse and as a switch. Install the automatic fuse at a distance of at least 50 cm from the boiler and heating appliances.
To connect an additional pump to the network in heating systems with forced circulation, it should be taken into account that one is already available and it turns on when the thermal relay is activated. For synchronous operation of both, the additional one must also be connected to a thermal relay or to a pump through a parallel connection.
In heating systems with an electric boiler, the circulation device can be connected directly to the boiler, as shown in the video on this page. Thus, the circulation system will only work when the water is heated.
Installation benefits
Installing a pump in heating systems with boilers of the Soviet period, and even later versions, will actually increase the efficiency of the boiler itself. With a functioning circulation device, the problem of uneven heating of radiators will disappear. By switching the water supply speed on the pump, it will be possible to regulate heat exchange. In addition, it prevents the formation of air locks in the system.
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Comments and reviews on the material
Remontmechty.ru
Selecting and installing a pump for a heating system with your own hands: 7 main rules
The traditional gravity heating system, in which the coolant moves naturally, has a number of significant disadvantages. These are uneven and non-simultaneous heating of heating devices, the difficulty of adequately regulating the temperature in individual zones, the need to use large-diameter pipelines, restrictions on the length and number of radiators. And also low efficiency. Installing a pump in the heating system, provided that it is done correctly, helps eliminate the mentioned disadvantages.
Heating pump. This type of equipment is sensitive to contamination by solid particles, and also quickly breaks down when operated without water. Neither one nor the other should be allowed
Why do you need a circulation pump?
The heating system pump ensures forced circulation of the coolant through the distribution pipes and heating devices. Due to the fact that pressure is created in the system, the liquid moves faster and there are no stagnant zones. All areas are heated simultaneously, regardless of their distance from the boiler. It is possible to use heating systems with high hydraulic resistance, for example water heated floors. Heating systems with pump circulation are able to serve buildings with large areas and high number of floors, which is beyond the power of gravity systems. An important fact: active coolant circulation allows you to avoid wasteful heat consumption and significantly reduce fuel consumption. The pump can be installed either in a new, originally designed circulation heating system, or in an existing gravity system.
Pump in a new circulation system
A significant part of modern heating boilers are already equipped with circulation pumps. Despite this, it is often necessary to install an additional pump in the heating system, possibly more than one. This happens for the following reasons:
- Standard pumps, as a rule, have low power and are designed for use in a very simple heating system with minimal hydraulic resistance. In practice, this rarely happens and there is a need to install an additional device.
- In complex branched systems, the hydraulic resistance of the circuits can vary quite noticeably and requires the installation of separate pumps. For example, a manifold for floor-to-floor distribution of underfloor heating pipes and additional buildings (bathhouse, utility room, garage) of a private house are always equipped with their own pumps.
For such a multi-circuit heating scheme, six circulation pumps were required
In a boiler room, it is preferable to install the main pump on the return line, although this is not a strict requirement.
Installation into an existing heating system
The circulation pump for the heating system can also be built into an existing gravity system. This will increase its efficiency, allow you to “remove” more power from the heating boiler, warm up areas far from the boiler, and reduce fuel costs.
A traditional heating system for a three-story house, with a pump added to increase its efficiency. Can operate in both gravity and circulation modes
To obtain the expected effect, the following requirements must be met:
- It is optimal to determine the installation location. It is better to install the pump in the heating system on the return line near the boiler.
- It is recommended to insert the pump not directly into the return line, but in parallel through the bypass. In this case, it can be turned off without consequences for maintenance or in the absence of electricity, while the heating will continue to operate in gravity mode.
The optimal installation of the pump is parallel to the main line, on which it is desirable to place a shut-off valve. Then the system will be able to operate in two modes: both circulation and gravity
- There is no need for constant operation of the circulation pump. It should only turn on when the temperature drops below the set value. Accordingly, automation will be required to control the operation of the pump. For this, various devices can be used, from simple relays with a temperature sensor to complex controllers linked to the automation of the heating boiler. The control type is selected based on the boiler model and heating circuit. Grounding is required!
One of the possible control schemes for circulation pumps
- Before installation, it is recommended to remove contaminants from the system; this can be done by flushing. It is recommended to install a filter at the coolant inlet to the pump to protect it from dirt. Note also that an open heating system with a pump is not the best solution. Dissolved oxygen penetrates into the coolant through an open tank, as a result of which all steel elements are destroyed by corrosion. It is not necessary, but highly desirable, when installing the pump to also replace the open tank with a closed membrane one.
- Installation should be carried out in strict accordance with the instructions, observing the orientation.
The rotor axis must be positioned strictly horizontally
- When starting the system, bleed air not only from the radiators, but also from the pump itself.
The screw located on the front part is designed to remove air
- The selection of a pump for a heating system must take into account the characteristics of the heating system.
Selecting a circulation pump
The selection of a pump for a heating system is carried out by calculation using rather complex formulas, taking into account the heat loss of the building, a special system, and the type of coolant. It is difficult for a non-professional to make an accurate calculation, but those who want to practice can download a program for calculating heating https://infobos.ru/str/756.html. There is also a simpler algorithm for approximate selection of the required characteristics:
- Flow (Q) is determined by the formula Q = N / (t2 – t1), where:
N – boiler power;
t1 – return temperature (in traditional systems 50-70 ºС);
t2 – supply temperature (75-90 ºС);
- We calculate the head (H) as follows: H = R x L x Zf, where:
H – head in meters, for closed systems is almost equal to the height of the system, measured in meters;
L – total length of all heating pipelines taking into account heating devices, m;
Zf is the coefficient of ball valves; in general, 1.3 can be taken.
The pumps for heating systems that are suitable for you must correspond to the pressure and flow characteristics of the system that have been determined. You should focus not on the indicators indicated in the brief description, but on the schedule in the technical data sheet.
In the passport attached to the pump there is a graph of pressure and flow characteristics; it is according to this that the selection should be made
Installing a circulation pump yourself is possible if you understand how to select and install it correctly, and also have the appropriate tools and skill in handling them. Otherwise, we recommend entrusting this work to professional heating engineers.
Video: choosing a circulation pump
teploguru.ru
DIY installation of a circulation pump in a heating system
Heating systems are always built according to two schemes - natural coolant circulation and forced movement. The second heating system always uses a circulation pump to force water through the pipes. At the same time, it is not at all necessary to observe the natural slope of the pipes, which makes the forced scheme more attractive to the consumer. Independent or professional installation of a circulation pump in the heating system is also necessary in two cases - if the heating pipes are laid with a counter-slope or if the heating boiler is not able to ensure natural circulation of warm water due to the long length of the pipes.
Installing a circulation pump will improve the efficiency of the heating system Circulation pump requirements
If the pump is installed in a working heating network (during the cold season), then the coolant is first drained. If the heating system has been in use for several years, then it must first be washed - fill it with water several times and drain it, getting rid of rust and solid inclusions.
The circulation pump is installed in heating systems operating on different fuels - solar, coal or wood, gas or electricity. Design of a circulation pump for a heating system
- Pressure height is the ability of a device to squeeze the coolant to a specific height. The unit of measurement is meter, in the instructions it is designated by the Latin letter “H”.
- Pumping a specific volume of coolant in a given time is called flow. The unit of measurement is m3/hour, denoted by the Latin letter “Q”.
The first characteristic is not critical, since the pump almost always operates in horizontal heating mains. Therefore, the main criterion when choosing a pump is the “Q” value. When operating a pump in a low-rise building, the main condition for squeezing the coolant onto the upper floors will be the complete filling of the system with coolant and the absence of air in it, and not the quality of the pressure. Due to the absence of air pockets, water will circulate constantly throughout the entire system. How to calculate the flow rate Q for a future pump? There is a standard formula: Q = N/(t2 - t1), where:
Modern heating boilers are manufactured with a circulation pump built into the housing, so for this unit there is no need to additionally equip it with a pump. But there are other solutions, for example: an old boiler model, extension of the heating system due to the addition of additional rooms, an error in calculations when choosing a boiler. In such cases, installing a circulation pump in the heating system becomes necessary.
How to install the pump
When installing a pump, there are only two options:
- Installing the pump as a separate unit.
- Pump insertion into the heating system.
Installation diagram of a circulation pump in a heating system Regarding the second option, expert opinions differ: where should the pump be installed - into the coolant supply pipe or into the return pipe? Be that as it may, the pumps work perfectly in any location. If we talk about the insertion itself, then experts do not advise inserting the pump directly into the pipe. For this, there is not only a wiring diagram, but also ready-made fragments for installing the pump in a pipeline made of any material (metal, PVC, metal-plastic), which can be purchased at a specialized store.
The pump is mounted in this way: an outlet in the shape of the letter “P” is attached to the main pipe by hot soldering or welding, into which the pump itself is cut in the center. There are valves installed on both sides of the outlet, the essence of which is as follows:
- When any valve is closed, the natural circulation of coolant in the heating system is restored.
- When both taps are closed, it is possible to carry out repairs or maintenance work in the heating system without draining the coolant.
Correct options for installing a circulation pump Pump in natural and forced circulation systems
When installing valves, ensure that the coolant flows correctly. The arrow on the valve indicates the direction.
- If the circulation pump is powered from the electrical network in a system with natural circulation of coolant, it is recommended to use an automatic fuse with a flag. Such an automatic fuse performs two functions at once - it protects the pump from overloads and serves as a switch for the unit. The fuse must be installed at a distance of 50 cm or more from all heating devices.
- When connecting an additional circulation pump in heating systems with forced circulation, keep in mind that the pump is already running and it turns on when the thermal relay is activated. To synchronize the operation of both pumps, the additional unit should also be connected to a thermal relay or in parallel with the main pump.
- If the heating system operates from an electric boiler, then it is recommended to connect the circulation pump directly to the boiler. This will allow the system to activate only when the coolant is heating.
Installation of a circulation pump in the heating system of a private house After the pump is installed and the coolant is filled, you need to open the special screw located on the pump cover to bleed air from the unit. First, using the Mayevsky tap, you need to bleed the air from the entire heating system. This is done with the pump(s) turned off.
What are the advantages of pump tapping
Installing a circulation pump in a heating system that uses an old-style boiler can actually increase the efficiency of the system. When the pump is running, all heating devices (radiators, registers and pipes themselves) will heat up constantly and evenly. The impeller rotation speed switch, and therefore the coolant supply speed, effectively regulates the heat exchange process in the system and does not prevent the appearance of air in the heating system.
Additional information about the correct installation and sequence of operations when installing the pump into the system will always be useful, even if you do not install it yourself, but resort to the services of professionals. Professional answers to tricky questions will help avoid disagreements between the masters and the owner.
Requirements for heating systems