Installation of the pump for heating. How to choose and connect a pump

To ensure the efficient operation of the heating system, very often you have to choose between installing large-diameter pipelines or installing pumping equipment. The advantages of the latter option are obvious.

Heat pumps for heating - this is the most common mechanism in apartments and houses with a modern autonomous system. Choosing the most optimal one from the variety of options available on the market, you can increase the heat transfer of the system, save energy, and prevent possible malfunctions and breakdowns. This article will discuss how to choose and how to connect the pump correctly.

Device and technology

So, before you purchase pumping equipment, you need to find out its device. It consists of the following basic elements:

• Compressor (works from the power supply network).
• Capacitor.
• Evaporator.
• Thermostat.
• Freon.

Under pressure, the freon enters the evaporator, where it evaporates, taking heat from the internal lattice of the evaporator. The evaporator, in turn, takes thermal energy from the water or soil circuit. The compressor raises the temperature of the evaporator freon by compressing it. Compressed freon enters the condenser, where it transfers heat to the heating circuit and becomes liquid. This process is continuous.

Source of energy

In order not to make a mistake when choosing a circulation pump , it must be taken into account that such equipment is divided into three main types. Their difference is energy sources: liquid, air and soil.

Liquid

Today, a system with such an energy source as water is particularly popular and effective. As a source, you can use both a water supply system and a reservoir - a reservoir, a lake, a river.

Air

In Russia, the most common equipment that operates due to air. This option is easy to translate into reality.

Priming

A system that operates due to ground energy is a rather effective option; it is preferable to use it for owners of private houses. It is distinguished by stability, since the range of fluctuations in soil temperature is practically not subject to strong changes.

Type of construction

In order to select a pump for heating correctly, it is necessary to pay attention to such criteria as the type of design. Pumps are divided into wet and dry rotor equipment.

Dry rotor

Dry rotor devices are isolated from the fluid being pumped. They are characterized by a high level of efficiency compared to a wet rotor. However, installing a pump for heating with a dry rotor has some difficulties. Due to the high noise level created by the dry rotor, it is necessary to install pumping equipment in a separate room. Also, these devices have large overall dimensions.

Wet rotor

Unlike the previous version, equipment with a wet rotor is much smaller. In this case, the pump is immersed in water, which simultaneously cools and lubricates the engine. The advantages include ease of use and the absence of difficulties when replacing individual structural elements.

Main characteristics

When selecting a pump for heating, in addition to having a manufacturer's warranty and various certificates, you should familiarize yourself with the following characteristics:

• Connecting the device, namely the diameter of the pipeline to which you plan to connect the pump. In most cases, the diameter of the pipeline ranges from 25 to 32 mm. In accordance with the diameter of the pipes, the heat pumps for heating are equipped with union nuts of the required size. This allows you to quickly install and disassemble them.
• Power. Information on this parameter is contained in the documentation for the pump itself. As a rule, this indicator is in the range from 60 to 300 watts. Based on this indicator, the temperature schedule of the heating system is determined. For private houses - up to 80 ° C.
• Performance. This is the volume of coolant entering the pipeline using a pump for a certain unit of time. This indicator directly depends on the cross-section of the pipelines of the heating system and affects its main indicators.
• The pressure. This criterion is measured by the long jet that a water pump produces for heating.
• Pressure. To make a competent calculation, it is necessary to clarify the length of all existing pipelines, and then multiply the obtained data by 100 Pa. Most often, the overall result is no more than 10,000. The characteristics of the pumps may not indicate the pressure, but the lift height, for example, 8 meters. Thus, for the designed system, designed to heat several floors, you should not choose low-power equipment with a lifting height of 4 meters.
  

Only after carrying out these calculations it will be possible to consider various options for pumping units, focusing on technical documents. Perhaps the calculation will show that installing a pump for heating is not required, and the coolant will circulate in a closed circle according to the laws of physics.

Criterias of choice

So, having found out the main characteristics of the heating pump, it is necessary to proceed to the selection of the optimal unit. First of all, you need to pay attention to the level of performance. The calculation method is as simple as possible: the boiler power is equal to the volume of liquid passed per minute. For example, with a power of 35 kW, the volume of the coolant will be equal to 35 liters.

Next, the flow rate of the coolant in a certain section of the circulation is determined. This will require data on the power of the heating devices, which is equivalent to the total flow of the coolant.

To calculate the flow rate of the coolant in the pipeline system, it is necessary to have a concept about the diameters used:

When performing the calculation, 1.5 m / s should be taken as the average velocity of the coolant in the pipeline.

For example, in order to calculate the power of the pumping equipment for the heating system over a 10-meter-long section, a head with a value of 0.6 meters is required. Accordingly, for the normal functioning of the 100-meter-long section, a pressure of 6 meters will be needed. And there remains only the choice and subsequent installation of the pump for heating, the technical characteristics of which will ensure the created conditions.

Pipelines with a small cross section are characterized by high hydraulic resistance, therefore, in this case, powerful equipment should be installed. For large-diameter pipelines, a high-performance pump can be neglected.

The above calculation is conditional, it can only be used for heating systems with a simple and straightforward scheme. In all other situations, it is more advisable to seek the help of heating specialists. If you are confident in your own strengths, then you can use the formulas for calculations presented in SNiP 2.04.05-91.

Installation of the pump in the heating system

1. First of all, as already mentioned above, it is necessary to decide on the choice of the pump unit. For this it is important to know that if the house has a radiator heating system and the area of ​​the premises is from 80 to 120 m ^{2, the} pump must process 0.4 m ^{3 of} coolant, with an area of ​​120 to 160 m ² - 0.5 m ³ .
2. The pump must be installed for heating in such a way that its motor shaft is horizontal. Since vertical placement can lead to air accumulation. At the same time, there is a significant obstacle to the normal lubrication of the bearings of the pump unit. Improper installation of the pump will lead to a reduction in the operational life or even its failure.
   
3. In a radiator heating system, it is preferable to install the pump near the boiler, and it is desirable to place it on the return pipe. Then, an expansion tank is connected to the return pipe.
4. Next, the boiler is turned off, all shut-off devices on the pump inlet and return are shut off. The nuts to which the pump is screwed are unscrewed. It is recommended that the pump set be equipped with a split thread and a filter. It is important that the filter and pump have identical diameters. If the heating system operates under pressure, a check valve should be purchased in advance.
5. After the pump is installed on the bypass line in the heating system, a check valve is installed, the terminal module must be located at the top. During installation, it is necessary to take into account the direction of movement of the coolant, which is marked on the device in the form of arrows. If an electric pump is used for heating, care should be taken to ground it.
6. Before starting, all air must be removed from the pumping equipment, the device itself can be turned on 5 minutes later. After switching on, it is necessary to remove the air again, only after that it will be completely ready for operation. If the pump warms slightly, there is nothing to worry about.

Cost

On average, a circulation pump with a capacity of 30 W, with a coolant flow rate of 2 m ³ / h and a pressure of 2 m costs 4300-4500 rubles. When choosing these devices, it is advisable to give preference to already trusted companies. For example, Danish heating pump Grundfos, German Wilo equipment or Italian units from manufacturers such as DAB, Lowara, Ebara or Pedrollo. Domestic manufacturers by and large are focused on the production of industrial pumps.

Today, consumers are more likely to choose a pump for heating Grundfos and Wilo, as units from these manufacturers have proven themselves in the best way.

Do not rely on the fact that it will turn out to choose equipment that will be 100% adequate. Since each heating system has its own nuances and operating features, and any equipment is focused on average parameters and indicators.

A pump that is too powerful during operation will generate a lot of noise, and a pump that is too powerful will not provide the required pressure in the system. For this reason, it is more advisable to purchase a pump with a capacity that will exceed the required by no more than 7-10%. It is advisable to give preference to models with a customizable mode of operation, which will allow you to use the equipment as efficiently as possible.