Why does the circulation pump heat up in the heating system? Causes and solutions to the problem

Here you will learn why the circulation pump heats up, how to avoid it, and what to do if your home heating system pump overheats.

Should the pump in the home heating system heat up?

During operation, the circulation pump may heat up slightly, which is not a malfunction. However, when it heats up too much, it indicates a problem, such as system clogging or incorrect pump selection. In this case, it is necessary to troubleshoot the issue and ensure its proper operation.

Why does the circulation pump heat up in the heating system? Causes and solutions to the problem

Principle of operation and device of the circulation pump

The circulation pump is designed to move fluid through the closed circuit of the heating system or hot water supply. Its principle of operation is based on creating a pressure difference at the inlet and outlet, which forces the fluid to move through the pipes.

The device of the circulation pump is quite simple. It consists of an electric motor, on the shaft of which a rotor with impeller is installed. The impeller is placed in the pump housing, which has guides on its inner surface for its movement. When the electric motor is turned on, the rotor starts to rotate, creating a centrifugal force that pushes the fluid from the suction port of the pump and directs it through the channels of the housing to the discharge port. Thus, the fluid is moved along the heating system circuit.

Main reasons for pump overheating

If the pump equipment overheats above the norm, it is necessary to first determine the cause of the overheating. The circulation pump can overheat for various reasons, including:

Why does the circulation pump heat up in the heating system? Causes and solutions to the problem
  1. When the system is clogged or has deposits, it increases the load on the pump, leading to overheating.

Solution: Clean the system or replace the pump.

  1. Worn-out or defective equipment operates less efficiently, causing overheating. In defective products, the motor winding or capacitor usually overheats. In such conditions, the pump will heat up even under ideal operating conditions. Since the electric motor is assembled in China or India, the thickness of the wire insulation is minimal. If even a small amount of moisture gets inside, the motor first starts to heat up, and then burns out. This usually happens with significant voltage fluctuations in the power grid. Defects manifest as irregularities and deposits on the inner surface of the pump spiral and housing. To prevent overheating of the circulation pump, the inner surface must be smooth, almost polished. Otherwise, energy losses increase, pressure decreases, and the pump housing starts to heat up.

Solution: Replace the pump.

  1. Lack of oil in the pump will cause friction between its moving parts, leading to overheating.

Solution: Add lubrication.

  1. Improperly installed pump may start to overheat.

Solution: Install the pump correctly.

  1. The pump does not match the heating system in power or other characteristics – this will cause overload and overheating.

Solution: Replace the pump with a more suitable one.

  1. If the system characteristics (volume, hydraulic resistance, etc.) do not match the pump characteristics, this will lead to its overload and overheating.

Solution: Select a pump considering the system characteristics.

Why does the circulation pump heat up in the heating system? Causes and solutions to the problem

In conclusion, by eliminating the cause of overheating, the pump’s operation can be normalized. In some cases, it may be necessary to replace the device with one more suitable for the heating system.

Causes of circulation pump noise

If the circulation pump is working correctly, it should not make any noise or hum. If such a problem arises, it is necessary to determine the cause precisely. The most common cause is the incorrect selection of the pump for the heating system. Before purchasing, it is necessary to determine the model and choose the one that fits the technical specifications.

The pump may hum or make noise when there is a mechanical malfunction. It needs to be eliminated by disassembling the mechanism. It may be necessary to replace adjustment washers and other malfunctioning parts.

Noises in the circulation pump may occur due to motor winding breakage or burning. Such breakdowns are difficult to fix without special knowledge and tools, so it is better to consult specialists.

Circulation pumps, like any equipment, can malfunction. One of the signs of malfunction is pump overheating during operation. This happens for various reasons, such as incorrect installation or contamination inside the pump. In any case, regardless of the cause, it is recommended to repair the breakdown as soon as possible, as there is a risk of equipment damage requiring replacement.