How to choose a circulation pump for a heating system: recommendations for the selection and installation of the unit

Heating systems with forced circulation of the coolant are very popular. They allow for quick and uniform heating of the entire room, regardless of its distance from the water heating unit. However, for this it is extremely important to choose the right circulation pump for the heating system. Otherwise, there will be problems.

Purpose and principle of operation

The circulating load ensures constant circulation of the coolant. It should be remembered that the unit must work all the time, since after its installation, the natural circulation of the liquid stops. Thus, the main requirements for the unit are:

• Sufficient performance.
• Low noise during operation.
• Reliability.

The practice of organizing heating systems has shown that the installation of a circulation pump can increase the efficiency of heating the room. The only drawback of using such a scheme is its dependence on electricity. Potential problems are solved by creating a backup power grid.

The principle of operation of the unit is as follows:

• The coolant enters the shell-shaped chamber.
• The pressure in the unit is generated by a flywheel located in the pump housing.
• The speed of movement of the liquid increases due to the centrifugal force.
• The coolant is discharged into a spiral channel connected to the water circuit.

During the circulation of water, the hydraulic resistance is reduced due to the swirling of the flow.

Main types

The principle of operation of the unit may differ depending on its design. Circulation pumps are usually classified depending on the type of rotor and the principle of control. On sale you can find models with a wet or dry rotor. In the first case, the coolant comes into contact with the impeller, and in dry units, the impeller is immersed in the liquid.

Models with a dry rotor are highly efficient, but generate a lot of noise during operation. That is why they are rarely used in heating systems for private houses. The main advantage of units with a wet rotor is a long service life of at least 7 years.

In everyday life, pumps with a mechanical adjustment system are most often used. They have a relatively low cost, but it is not very convenient to maintain the required temperature in the room when using them.

If possible, then it is worth giving preference to electronically controlled units. Thanks to the automatic control system, energy costs can be cut by about half.

Features of choice

First, you need to analyze the parameters of the room and the hot water equipment used. You will also need to decide on the main functions that the unit will perform, in addition to increasing the speed of movement of the coolant, which is the main one. When choosing a circulation pump, you must focus on the following points:

• Unit power.
• Manufacturer.
• Pump functionality.

Power calculation

The selection of the unit, depending on the area of ​​the building, can be done only after carrying out a thermal analysis of the premises and the heating system. This is an expensive procedure that is carried out in industrial facilities and in the construction of apartment buildings. When designing a heating system in household buildings of a small area, it is quite possible to do without the use of formulas. To do this, you need to study the technical characteristics of the circulation pump for heating. You can choose an aggregate in such a situation in the following way:

• Taking into account the performance of the heating boiler - for 1 kW of water heating equipment power, it is necessary to use equipment with a throughput of 1 l / min. For example, if a 25 kW boiler is installed, then a pump capable of operating at a speed of 1500 l / h is required.
• In terms of the head of the unit - this characteristic is indicated in the technical documentation of any product, and the unit of its measurement is a meter of water column. For every 10 meters of pipeline, a pump with a pressure of 0.6 meters of water column must be used.

Leading manufacturers

The price and quality of the pump largely depends on the manufacturer of the equipment. It is impossible to focus solely on the cost of the unit. When choosing it, it is worth studying the reviews, as well as technical specifications. Based on the opinion of consumers and the number of products sold, the products of the following companies can be considered the best choice:

• Grundfos is one of the leaders in the design and manufacture of pumping equipment. According to official statistics, about half of all products sold in the world belong to this manufacturer. German pumps are highly reliable and efficient.
• Wilo is another manufacturer from Germany. The company's products are also of high quality, and a large number of household models can be found in the product line.
• DAB is a company from Italy with extensive experience in the creation of pumping equipment.
• UNIPUMP is a Russian brand that can compete with the world leaders in this market segment. With a relatively low cost of the units, they are distinguished by good workmanship.
• Oasis - products are made in China. The popularity of the brand was brought about by the low cost of the pumps with fairly good properties.
• Wester is a brand that produces quality equipment, but in a limited range.

Functionality

When choosing a pump, there are several useful features worth paying attention to. First of all, we are talking about the method of controlling the unit. It is advisable to purchase a pump with an electronic unit. Automation is connected to a thermostat, which allows you to regulate the pressure and speed of the coolant without human intervention. Of course, mechanically controlled pumps have a more attractive cost, but their operation is associated with certain inconveniences.

A good bonus to the unit will be a pressure relief system and air removal from the system. It is also worth paying attention to the function that prevents the cold start of the unit. Some models may be equipped with a pressure relief valve. It is designed to eliminate emergency situations that are possible when the coolant is heated to the boiling point.

Installation rules

The installation diagram of the unit can be found in the instructions. If the pump is installed by the user independently, then first you should study the manufacturer's recommendations. Most often they relate to the following points:

• The installation of a closed heating system should only be carried out with a backup power supply. At the same time, its battery life should be at least 4 to 6 hours.
• If a one or two-pipe heating system is used, then it is necessary to provide for the installation of a bypass. This is especially true for regions with frequent power outages.
• It is strictly forbidden to turn on the pump in a system without a coolant. To check the efficiency of the heating, the water circuit must be filled with liquid.
• The instructions indicate the diameter of the pipes to be used in the heating system.
• A coarse water filter must be installed in front of the unit.

The choice of pumping equipment for the heating system must be approached with full responsibility. Don't skimp on the pumpby purchasing products of unknown brands at a low cost.

If you have certain technical skills, then you can install the pump yourself. Otherwise, this work should be entrusted to professionals.