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Installation of circulator pumps

An electronic circulation pump is nowadays an essential part of any building's heating. It provides circulation of water from the heat source to the heating system, such as radiators or underfloor heating. Improper installation can lead to lower heating performance, but also to damage to the heating system. Therefore, installation should not be neglected. What do you need to think about?

Placement of circulator pump

For the correct function of the circulator pump, its proper placement within the heating system is important. This should be determined by the professional who designed your house or heating system.

However, if you decide to install it yourself, there are basically two ways to place it - either on the return piping through which cold water flows to the boiler, or on the hot water discharge line coming from the boiler. In the past it was recommended to place circulators exclusively on cold water pipes due to possible heat damage. Modern circulators are made of materials that withstand even high temperatures. Therefore, if for some reason you cannot install the pump on the return line, you can easily install it at the beginning of the circuit.

It is also worth remembering that the circulator pump should be easily accessible for possible repairs or future settings.

Replacing an old pump

If you are replacing an old circulation pump in an existing heating system, you need to pay atention to certain parameters when purchasing a new one. Above all, the new pump should have the same hydraulic power, construction length and diameter of the connecting threads. However, if you change the circulation pump due to an increase in the area of underfloor heating or the number of radiators, it is necessary to adjust parameters to the new conditions.

Take extra care when removing the old circulator pump. There may be hot water in the pump, also under high pressure, therefore there is a risk of scalding. Drain the pump carefully before disassembly.

The head of the pump is not determined by the height of the house, but by the length of the pipe.

Mechanical installation of a new pump

If you already selected a place to install the circulation pump, and if you have removed the old pump, it is time to install your new one. First, assemble the circulator system as follows:

It is necessary to have valves on both sides of the pump, which will allow the water flow to be stopped in case of repair or removal of the pump. Screw the valves onto the pump threads. Sometimes the tap can be installed only in front of the pump, and a check valve can be placed behind the pump, but with regard to higher safety and comfort when handling the pump, it is better to have two valves. You can also replace the valves with a camlock fitting, which is closed with an Allen key.

A filter, which catches any dirt and prevents clogging of the pump, must be placed in front of the pump and in the direction indicated by the arrow on the filter. Place a non-return valve behind the pump. If the vent filter is not part of the pump itself, connect it to the system. All connections must be properly sealed with a heating gasket, preferably rubber. Mount the pump system assembled in this way on the heating system pipes using a brass fitting.

See possible positions of the circulation pump in the instructions for the specific model, but usually you can choose a vertical or horizontal position. However, it is always necessary to keep the direction of water flow, which is shown by the arrows directly on the pump. At the same time, the switching box must not be above the pump, as this would prevent the pump from being properly vented.

Your pump must be de-energized during installation!

Connecting your pump to the mains

Once you have successfully installed the circulation pump, it must be connected to the power supply. The pumps are supplied with 230 V as standard. Check for your specific pump.

In addition to the pump motor itself, depending on the specific model, it is also necessary to connect a control unit and heat sensors. Circulation pump is a relatively complicated electronic device, and therefore its installation into the network can be performed only by an authorized person. Improper wiring could lead not only to damage to the pump, but especially to injuries.

A suitable accessory for the circulating pump system is a backup power supply, which ensures its uninterrupted operation in the event of a power failure.

Installation of multiple circulators

The required number of circulation pumps is determined by the length of the piping. As a rule, one pump per 80m pipe is sufficient. If you have longer pipes or underfloor heating, it is recommended to install more circulation pumps. Otherwise the pressure would not be sufficient and the hot water distribution in the heating system would be uneven.

If you have more than one boiler, it is necessary to have at least one pump for each. If you install more than one pump on one boiler, it is advisable to connect a so-called annulus, which balances the pressure in the boiler. Excessive pressure could damage the boiler if several pumps are running at the same time.

Starting the circulation pump

Prior to first start it is necessary to bleed some pumps and set the required mode, resp. performance. Non-vented pumps are noisy and can be permanently damaged. However, some modern circulators are bled and adjusted automatically.