Common faults of chiller

1. The evaporation pressure is too low:
Reason:
(1) The amount of cold water is insufficient.
(2) Less cooling load.
(3) Throttle orifice failure (only makes the evaporation pressure low).
(4) The heat transfer tube of the evaporator is deteriorated due to scale and other pollution (only the evaporation pressure is too low).
(5) The amount of refrigerant is insufficient (only the evaporation pressure is too low).
Solution:
(1) Check the cold water circuit to make the cold water volume reach the rated water volume.
(2) Check the set temperature of the automatic start-stop device.
(3) Check whether the expansion throttle tube is unblocked.
(4) Clean the heat transfer tube.
(5) Supplement the refrigerant to the required amount.
2. Condensing pressure is too high:
Reason:
(1) The amount of cold water is insufficient.
(2) The capacity of the cooling tower is reduced.
(3) The temperature of the cold water is too high and the cooling capacity is too large, which increases the load on the condenser.
(4) There is air.
(5) The heat transfer of the condenser tube is deteriorated due to scale and other pollution.
Approach:
(1) Check the cooling water circuit and adjust to the rated flow.
(2) Check the cooling tower.
(3) Check the expansion throttle tube, etc., so that the temperature of the cold water is close to the rated temperature as soon as possible.
(4) Carry out air extraction operation to remove air. If the air extraction device needs to be operated frequently, it is necessary to find out the part where the air leaks in and eliminate it.
(5) Clean the pipe.
3. The oil pressure difference is too low:
Reason:
(1) The oil filter is clogged.
(2) The opening of the oil pressure regulating valve (drain valve) is too large.
(3) The output oil volume of the oil pump is reduced.
(4) Bearing wear.
(5) The oil pressure gauge (or sensor) is out of order.
(6) There is too much refrigerant mixed in the lubricating oil (the oil pressure is too low due to oil foaming at startup).
Approach:
(1) Replace the oil filter element.
(2) Turn off the oil pressure regulating valve to increase the oil pressure to the rated oil pressure.
(3) Disassembly inspection.
(4) Replace the bearing after disassembly.
(5) Check the oil pressure gauge, recalibrate the pressure sensor, and replace it if necessary.
(6) Be sure to switch on the oil heater after the refrigerator stops to maintain a given oil temperature (confirm whether the oil heater is disconnected and whether the setting value of the oil heater temperature control is correct).
4. The oil temperature is too high:
Reason:
(1) The cooling capacity of the oil cooler is reduced.
(2) The supply of refrigerant for cooling the oil cooler is insufficient due to clogging of the refrigerant filter.
(3) Bearing wear.
Approach:
(1) Adjust the oil temperature regulating valve.
(2) Clean the filter screen of the refrigerant filter.
(3) Repair or replace the bearing after disassembly.
5. Main motor overload:
Reason:
(1) The phase voltage of the power supply is unbalanced.
(2) The voltage drop of the power line is large.
(3) The amount of cooling refrigerant supplied to the main motor is insufficient.
Approach:
(1) Take measures to balance the phase voltage of the power supply.
(2) Take measures to reduce the voltage drop of the power line.
(3) Check the filter screen of the refrigerant filter and clean the filter screen; open the refrigerant inlet valve