Chiller, also known as freezer, refrigeration unit, ice water unit, cooling equipment, etc., is a multi-functional refrigeration equipment. Its working principle is mainly to remove liquid vapor through compression or heat absorption refrigeration cycle, so as to achieve the refrigeration effect. As an operation operator, mastering the monitoring skills of "look, touch, listen, think and check" can effectively achieve this goal.

I. Look

Observe the shape and components: check whether the shape of the central air conditioning is intact, and whether the various components such as compressors, condensers, evaporators, fans, pipelines, etc., are working normally, and whether there is obvious damage or deformation.

Check pipes and welds: Carefully check whether the pipes of the refrigeration system are broken, and whether there are oil traces in the welds. An oil stain on the solder joint could mean a leak.

Electrical components and connections: Check whether the inserts of electrical components are loose, whether the positions of the connected copper tubes are correct, and whether the copper tubes touch the shell.

Observe the wind blade and vibration: check whether the pulsation of the centrifugal wind blade and the axial flow wind blade is too large, and whether the motor and compressor have obvious vibration.

Check the pressure and temperature: Observe whether the high and low pressure pressure values are normal, and the frost formation of the low pressure part of the capillary. In normal refrigeration, at the beginning of the compressor operation, the capillary tubes will be covered with a thin layer of frost, and then gradually melted away.

View operating parameters: Record and observe the operating parameters of the central air conditioner, such as cooling capacity, heat production, power consumption, energy efficiency ratio, etc., to evaluate its performance.

Two, touch

Touch the surface of the evaporator: the temperature of the normal air conditioner evaporator should be the same, the surface is cool, and there is condensation at the exposed copper pipe elbow.

Touch the surface of the condenser: after the air conditioner is turned on, the condenser will soon heat up, and the faster the heat, the faster the refrigeration. Under normal use, the temperature of the condenser can reach about 80 degrees.

Touch the low pressure return pipe: When normal, the suction pipe is cold and the exhaust pipe is hot. If the ambient temperature is low, there will be condensation water on the surface of the low-pressure return pipe. If the return pipe does not condense, the high pressure exhaust pipe is hot, and the compressor housing is very hot, it is likely that the refrigerant is insufficient.

Touch the high-pressure exhaust pipe: the hand should feel relatively hot, and the hand is hot in summer.

Touch the filter dryer: Under normal conditions, the surface of the filter dryer feels slightly higher than the ambient temperature. If there is a cold feeling or condensation, it indicates that the filter dryer is slightly blocked.

Touch the outlet: the hand should feel some cool wind, stay for a long time will feel cold.

Iii. Listening

Listen to the running sound of the whole machine: When the air conditioner is running, it will make a certain sound. Carefully listen to whether the sound of the machine is normal. If there is an abnormal sound, such as "buzzing", "hiss", "tap", etc., it may indicate that the compressor, fan, or other components have problems.

Listen to the compressor sound: pay special attention to the compressor running sound. Compressor is the core component of central air conditioning, and its sound change can often reflect its working state. If you hear abnormal sound of the compressor, stop the machine immediately for inspection.