Selecting a circulation pump for a heating system

The material was prepared with the participation of experts from Wilo .

The past winter heating period with severe frosts, sudden thaws and frequent transitions through 0 could reveal all the pros and cons in the operation of the heating system of a country house. As a result, depending on the efficiency of the equipment, homeowners either spent the planned funds on heating the cottage, or overpaid and thought about how to reduce costs in the next heating season.

There are several ways to modernize your heating system and thereby reduce operating costs in the long term. One of them is to equip the “engineer” with a circulation pump that flexibly adapts to constantly changing operating conditions. We are looking into the issue with the help of an engineer from a circulation pump manufacturer.

• What are the features of a modern heating system?
• Why do you need a circulation pump with an intelligent control system?
• What is the operating principle of circulation pumps with an electronic control system based on?
• What is the economic benefit of using a “smart” circulation pump.

Which pump is better to buy for a home heating system?

The first step when choosing a pump is to individually calculate the required performance. It depends on many factors, different for each room. These include area, number of radiators, length of the water circuit, pressure in the system, etc.

Pump performance is calculated using the formula: Q=N/(t2-t1)

where Q is fluid flow,

N is the power of the heating boiler,

t1 and t2 are the water temperature in the return and supply pipes of the heating circuit, respectively.

On average, to provide heat to a room of 10 m², a boiler power of about 1 kW is required. Water at a temperature of 90-95 °C is supplied to the system, and 60-70 °C is received at the return. Knowing these numbers, you can quickly estimate the minimum pump performance for a particular house or apartment with an individual heating system.

For comfortable use of the heating system, we recommend taking into account the possibility of regulating the speed of fluid movement through the pipes.

Fast circulation will provide high heat transfer, but if the climate changes favorably, the room will become too hot. The speed variator will allow you to control the temperature yourself and save energy.

An important characteristic of the pump is the permissible pressure. It determines the maximum level to which the device is capable of raising water in the heating system.

For residents of one-story houses, an indicator of up to 2 atmospheres will be enough. More complex heating circuits installed in cottages will require a pump pressure of about 3-4 atm.

Before installing the pump, the insertion location must be correctly determined. It is affected by the maximum temperature that the device’s construction materials can withstand. A value of more than 110 °C will allow you to install the device not only on the return pipe, but also on the supply pipe.

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Content

There are two circulation systems - classical and forced.
In the first case, the heating system device must contain a vertical pipeline in its design, where natural circulation of water occurs under pressure. In the second option, circulator pumps are used, which forcibly produce regular circulation of water. Such pumps are included in the design of most modern heating systems, and their presence guarantees the maintenance of uniform temperature in the room over its entire area.

How to choose a suitable circulator pump for a heating system and what should you pay attention to first?

When operating the heating system, it is necessary to use coolant circulation

The best dry-running pumps for home heating systems

The design of such models assumes the presence of a system of sealing rings that limits contact of the rotor with water. Dry-running pumps are characterized by high efficiency and economical electricity consumption. However, they require regular maintenance and are noisy when operating.

DAB ALP 2000 T

5.0

★★★★★

editorial assessment

100%

buyers recommend this product

The model is characterized by uninterrupted operation in various heating systems. The device uses water or a mixture with ethylene glycol as a coolant. A technopolymer impeller, corrosion protection and a robust casing guarantee a low degree of wear on the main components of the pump.

Thanks to the ability to select a reduced shaft rotation speed, you can reduce the noise level of the device and save on electricity. The maximum liquid temperature is 120 °C, the pressure is up to 21 meters. The small dimensions of the pump simplify installation of the device at any point in the system.

Advantages:

• high performance;
• liquid temperature is allowed within -15..+120 °C;
• stable work;
• economical energy consumption.

Flaws:

• high price.

DAB ALP 2000 T is designed for installation in private homes or low-rise buildings. A high protection class and pressure of up to 10 atmospheres ensure stable operation of the pump in a branched system.

VALTEC VSB 04-15

4.9

★★★★★

editorial assessment

95%

buyers recommend this product

The main features of the model are low noise level and ease of installation. The pump body is made of brass and is easily attached to the cast iron motor block using a union nut.

The maximum pressure of the device is 10 atmospheres, the throughput is 0.7 cubic meters per hour.

Due to the permissible ambient temperature from +4 to +50 °C, the device can be installed not only in a residential area, but also in an adjoining room.

Advantages:

• high pressure;
• ease of installation;
• low cost;
• silent operation.

Flaws:

• short cable.

VALTEC VSB 04-15 is unpretentious to operating conditions. It is worth purchasing for installation in a country house or outbuilding. The pump ensures stable operation of radiators and can be connected to a “warm floor” system.

JEMIX W15GR-18 A

4.8

★★★★★

editorial assessment

91%

buyers recommend this product

The features of the model include durability and ease of operation. The device is controlled by a switch on the terminal box. Three operating modes are available to the user, allowing you to customize the operation of the pump depending on current needs.

The device operates from a 220 V electrical network and is capable of raising water to a height of up to 18 meters. The cast iron body of the device and the permissible liquid temperature of 110 °C allow it to be installed at any point in the pipeline.

Advantages:

• long service life;
• ease of adjustment;
• ease of installation;
• productivity - 30 l/min.

Flaws:

• body heating during operation.

Jemix W15GR-18 A will be an excellent solution for a private home or cottage. Simple setup and high pump performance will ensure stable coolant circulation.

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Selection issues

For a specific facility, the heating pump is selected taking into account the hydraulic characteristics of the system. Naturally, the system parameters are calculated by specialists in advance based on:

• climatic conditions of the region
• degree of building insulation
• thermal insulation properties of floor and ceiling
• sealing windows, doors, etc.

The result of such calculations is the determination of the volume and temperature of the coolant that should be regularly supplied to the room. The value is expressed in cubic meters per hour and is a key component of pump productivity. In addition, its pressure must prevail over the hydraulic resistance of the system.

When choosing a specific model, it is advisable to ensure that its technical characteristics are slightly lower than the maximum required. The device will not experience any special overloads, but idle operation can be avoided. In addition, devices that are not fully loaded create unwanted noise in the heating mains.

The best wet-running pumps for home heating systems

Models of this type have insulation only of the stator and other elements of the electric motor, while the rotor and impeller are in contact with the coolant.

Wet-running pumps are reliable, low-noise and do not require frequent maintenance, but have a low efficiency of about 50% and low power.

GRUNDFOS UPS 32-80 180

5.0

★★★★★

editorial assessment

100%

buyers recommend this product

See review▶

The main features of the model include flexible operation settings and economical energy consumption. It is ensured by selecting the speed mode of shaft rotation using a switch on the terminal box.

The device also has the ability to operate on a timer and with automatic performance control. The maximum pressure is 10 atmospheres, the liquid temperature is allowed within the range from -25 to +110 °C.

Advantages:

• easy connection;
• long service life;
• speed setting;
• silent operation.

Flaws:

• high price.

Grundfos UPS 32-80 180 produces a pressure of up to 8 meters and is designed for installation in one-story houses. An excellent choice for both closed and open-loop heating systems.

WILO Star-RS 25/2

5.0

★★★★★

editorial assessment

97%

buyers recommend this product

The reliability of the model is ensured thanks to a blocking current-resistant electric motor, a perforated stainless steel shaft design and a water filtration system.

Maximum pressure is 2 meters, productivity is 2.2 m³/h. Support for horizontal shaft positioning and double-sided connection of the terminal box make it easy to install the pump in various places in the pipeline.

Advantages:

• durability;
• ease of installation;
• low price;
• economical energy consumption.

Flaws:

• lack of fastenings in the package.

Wilo Star-RS 25/2 is suitable for home use. Quiet operation and a five-year warranty make the pump comfortable and reliable.

GILEX "Compass" 25/80

4.8

★★★★★

editorial assessment

88%

buyers recommend this product

Thanks to a convenient valve located on the body of the model, the user has the opportunity to quickly release air that accidentally gets into the heating system. This ensures uniform heating in all areas.

A three-mode shaft rotation speed switch ensures economical energy consumption and comfort during use. The noise level during pump operation is 45 dB, the maximum pressure is 8 meters.

Advantages:

• protection of fastenings from corrosion;
• speed shifter;
• air valve;
• low noise level;
• overheat protection.

Flaws:

• requires regular flushing of the system.

"Compass" 25/80 can be used in multi-stage heating systems. The right solution for installation in large buildings or low-rise buildings.

Installing a circulation pump with your own hands (step-by-step instructions)

The choice of location for installing the pump is a very important point. The type of system and the operating principle of the entire installation should be taken into account.

The pump can be installed at both the inlet and outlet - the main thing is to ensure comfortable access to the device. This is necessary for inspection, maintenance and prevention.

Despite two possible placement options, most often the device is installed at the entrance. This installation option ensures pumping water at a lower temperature, but the most important criterion should remain ease of access.

The best budget pumps for home heating systems

Such models are in the price category of up to 5 thousand rubles and are characterized by low power and performance. However, they are very stable in operation, have small dimensions and do not require specialized care.

CALIBER NTs-25/8-180

4.8

★★★★★

editorial assessment

89%

buyers recommend this product

The pump is driven by a single-phase asynchronous motor. The unit is distinguished by the presence of three power modes, characterized by maximum productivity from 3.6 to 9 cubic meters per hour.

Compact dimensions and operation with coolant temperatures up to 110 °C allow the device to be installed on any part of the heating system. A pressure of 10 atmospheres ensures stable operation in multi-storey buildings.

Advantages:

• small dimensions;
• ease of installation;
• 3 power modes;
• quiet work.

Flaws:

• instability to moisture and dust.

CALIBER NTs-25/8-180 is installed in residential buildings. It is worth purchasing for an extensive heating system in a country house or cottage, which includes a network of radiators and a “warm floor” system.

VORTEX TsN-32-6

4.8

★★★★★

editorial assessment

87%

buyers recommend this product

The advantages of the model include a long service life and adjustable pumping speed. The latter is done by rotating the impeller, which allows you to adjust the temperature as accurately as possible.

Stable operation over a long period of time is ensured thanks to the durable cast iron body, natural lubrication and cooling of the bearings, as well as the ability to remove air from the system.

Advantages:

• silent operation;
• durability;
• speed adjustment;
• small dimensions.

Flaws:

• weak pressure.

VORTEX TsN-32-6 is designed for installation in small areas. It is used in one-story houses, small apartments or commercial buildings.

UNIPUMP CP 25-60 180

4.7

★★★★★

editorial assessment

85%

buyers recommend this product

See review▶

The device's engine is protected against overheating, which ensures long-term operation under high loads.

The maximum productivity of the model is 53 liters per minute. The fluid pumping speed is controlled using a three-stage controller.

It is permissible to use not only water, but also other low-viscosity liquids as a coolant.

The pressure in the system is up to 10 atmospheres, due to which the pump remains stable when operating in highly branched heating systems.

Advantages:

• thermal protection;
• high pressure;
• performance;
• speed controller.

Flaws:

• no liquid filtration.

UNIPUMP CP will perform well in a one-story building. High performance makes it possible to successfully use the pump in large areas or to ensure the circulation of coolant in a single system for several buildings.

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Recommendations from an expert

The pump must be installed in accordance with the following rules:

• It is mandatory to install a bypass, which will ensure the movement of energy through the system during a power outage;
• the check can only be carried out if the system is completely filled;
• It is imperative to install a coarse filter.

Important!

1. Bypass is a small section of pipe built into bypassing the circulation pump.
2. It is advisable to install a filter for fine cleaning.

If you carefully look at the photographs with installed circulation pumps, you will certainly notice that devices with a wet rotor are always mounted vertically!

The best premium pumps for home heating systems

Models in this category are distinguished by high performance and power. They are used in multi-storey residential buildings or enterprises.

Such pumps are very expensive, but they have flexible settings, ease of control and are extremely reliable.

ESPA RE1-F SAN SUP 40-80-B 230 50

5.0

★★★★★

editorial assessment

100%

buyers recommend this product

The device has a lightweight design and is easy to install. It is equipped with an LED display and a three-stage electronic power regulator, which makes it easy to control operating modes and all key parameters.

The automatic setting function sets the most suitable pressure according to your current needs. Thanks to the use of a permanent magnet motor, energy savings of up to 70% are achieved.

Advantages:

• flexible setup;
• information screen;
• saving electricity;
• quiet operation;
• remote control.

Flaws:

• high price.

ESPA RE1-F SAN SUP 40-80-B 230 50 has a capacity of up to 35 cubic meters per hour. Such a pump can be installed in industrial buildings or large residential buildings with a multi-stage heating system.

AQUARIO AC 14-14-50F

4.9

★★★★★

editorial assessment

94%

buyers recommend this product

A special feature of the model is the high pressure indicator. A durable cast iron body, technopolymer impeller, natural lubrication and cooling of components help extend the service life of the device.

The maximum pump performance is 466 liters per minute, pressure 10 atmospheres. The device is silent during operation and easy to install due to its compact size and simple threaded connection.

Advantages:

• long service life;
• high performance;
• small dimensions;
• silent operation.

Flaws:

• lack of speed controller.

Aquario AC 14-14-50F will be an excellent purchase for installation in a multi-storey building. A pressure of up to 16 meters guarantees stable operation of the pump in a branched system.

Comparison table of the presented models

All of the above technical parameters of each model are presented in the table.