Fault analysis of fan coil unit with small wind noise, temperature deviation and water leakage
Details
1.the fan coil unit air volume is small, poor cooling capacity: Under the condition of normal operation of the fan, air leakage in the air duct is rare and easy to handle, and many reasons for the small air intake are caused by blockage of the filter screen at the return air outlet. The solution is to clean the filter screen frequently. If it is not cleaned in time, dust and sundries 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, resulting in smaller blade angle, lower air volume and higher fan current. Therefore, it is very necessary to clean the filter screen of the air return port. Generally, it should be cleaned at least once every quarter, otherwise the blockage will become more and more serious and the maintenance will become more and more difficult.
2. Loud noise of fan coil unit: There are some reasons for the high noise of fan coil. When the coil is in operation, its blades, fan, fan shaft and unit shell are in vibration state. If the coil is used for a long time, the surface of its components will have turbidity embroidery and oil stains, which will make the components friction and vibrate violently, and the released noise will be comparable. When there is air flowing inside the coil unit, noise will be generated when it passes through the return air filter screen, the air moves in the unit, the wind blows the fins of the heat exchanger and the air moves in the fan.
Common causes of loud noise of fan coil unit: (1) the fan coil unit is not installed firmly, resulting in system resonance; (2) The fan motor bearing is worn, which causes the fan motor to run eccentrically and produce noise; (3) The fan blades deform and scrape other parts; (4) The fan coil unit is deformed during transportation or installation, which makes the fan bearing or bearing seat misaligned and produces noise. (5) It has a great relationship 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.fan coil motor does not turn: Check whether the fan coil unit power supply is normal by powering on; if there is no power output, check whether the power supply is faulty; Then check the speed control switch. If the above two conditions are not true, check whether the impeller is stuck. Because the electric power of the fan coil unit is relatively small, a little resistance may be stuck. At this time, we need to observe and check in time. Contact the maintenance personnel immediately.
4. The air output of fan coil unit is normal, and the air supply temperature has deviation: Most of these faults occur in the coil water supply and return system. First, check whether the water supply temperature and water quantity are normal. If the temperature difference between supply and return pipe is large, it is mostly caused by blockage of inlet filter or gas in pipeline.
In addition, sharp bends, slag deposit points and gas gathering points should be avoided as far as possible in the construction process. Although the specification requires that exhaust valves and sewage valves should be set at high points and low points, it is often difficult to realize them in the construction site. Flush and drain as much as possible after installation. Clean the water filter frequently during operation to keep the pipeline unblocked.
5. Leakage of fan coil unit: (1) If the water leaks outside the fan coil water collecting tray, it is mainly because there is something wrong with the insulation material, which needs to be strengthened and can be eliminated.
(2) If the water leaks in the water collecting tray, it means that the condensate pipe of the fan coil unit is not smooth, and the condensate water overflows. We only need to dredge the condensate pipe, or purge it with a gas cylinder.
(3) If the condensate drain pipe is always blocked, water will often leak down from it. Besides cleaning it regularly, it is recommended to thoroughly wash and scale it systematically, and check whether the filter screen is added to the air return outlet of the fan coil unit and whether the installation slope of the pipe meets the requirements.
