Knowledge!Common faults of fan coil units

small air output and high noise, temperature deviation, water leakage, and motor does not rotate.

1. The air output of the fan coil is small and the cooling capacity is poor:

When the fan is running normally, in addition to the small air inlet volume and air duct leakage, air duct leakage rarely occurs and can be easily dealt with. The small air inlet volume is often caused by the blockage of the return air inlet filter. The solution is to clean the filter frequently. If it is not cleaned in time, dust and debris will further stick to the coil fins and wind wheel blades. If the fins are blocked by dirt, the ventilation capacity of the fan will decrease. Dust will also accumulate on the fan impeller, causing the blade angle to become smaller, thereby reducing the air volume and increasing the fan current. Therefore, it is very necessary to clean the return air filter. Generally, it should be cleaned at least once a quarter, otherwise the blockage will become more serious and maintenance will become more and more difficult.

2. The fan coil unit is noisy:

There is a certain reason why the fan coil unit is noisy. When the coil unit is in operation, its fan blades, fan, fan shaft and unit casing are in a vibrating state. If used for a long time, the surface of its parts will appear turbid and oily. This will cause the parts to have large friction, violent vibrations, and the noise released will also be loud. When there is air flowing inside the coil unit, noise will be generated when it passes through the return air filter, the air moves in the body, the wind blows on the heat exchanger fins, and the air moves in the fan.

Common causes of loud fan coil noise:

The fan coil unit is not installed firmly, causing system resonance;

The fan motor bearings are worn, causing the fan motor to run eccentrically and produce noise;

The fan blades are deformed and other parts are scratched;

The fan coil unit may be deformed during transportation or installation, causing the fan bearings or bearing seats to become non-centric and produce noise.

It also has a lot to do with the winding of the motor itself. If there is no fundamental change in the high-speed gear after replacing the capacitor, it is recommended to replace the motor directly.

3. The fan coil motor does not rotate:

Turn on the power and check whether the power supply of the fan coil unit is normal. If there is no power output, check whether the power supply is faulty; then check the speed control switch. If neither of the above conditions is the case, check whether the impeller is stuck. The power of the tube motor is relatively small, and it may get stuck if there is a little resistance. At this time, we need to observe and inspect in time. Contact maintenance personnel as soon as possible.

4. The air output of the fan coil unit is normal, but the supply air temperature deviates:

Most of these failures occur in the coil water supply and return system. First check whether the water supply temperature is normal and the water volume is normal. If the temperature difference between the water supply and return pipes is large, it is mostly caused by the water inlet filter being clogged or the air trapped in the pipes.

In addition, sharp bends, slag accumulation points and gas collection points should be avoided as much as possible during the construction process. Although the regulations require that exhaust valves and sewage valves should be installed at high and low points, it is often difficult to implement them at the construction site. After installation, flush the drain as much as possible. During operation, the water filter should be cleaned frequently to keep the pipeline smooth.

5. Fan coil leaks:

If water leaks outside the fan coil water collection pan, it is mainly due to a problem with the insulation material, which needs to be strengthened and can be eliminated.

If water leaks in the water collection pan, it means that the condensation water pipe of the fan coil is not clear and the condensation water overflows. We only need to clear the condensation water pipe, or purge it with a gas cylinder.

If the condensate discharge pipe is always blocked and water often leaks from it, in addition to cleaning it regularly, it is recommended to thoroughly flush and descale the system, and check whether the return air outlet of the fan coil is equipped with a filter. Whether the pipe installation slope meets the requirements.

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