1. The compressor does not work
Cause Analysis:
①Incorrect wiring ②Low voltage ③Open circuit of the restrictor ④High exhaust pressure ⑤The thermostat is normally open ⑥The piston is stuck ⑦Lack of refrigerant
Troubleshooting:
①Check the wiring ②Check the line power supply ③Reset ④Remove the cause of the high pressure ⑤Repair or replace ⑥Replace the compressor ⑦Replenish fluid
2. Short cycle of the freezer unit
Cause Analysis:
①Exhaust valve leakage ②Reverse evaporator fan ③Lack of refrigerant ④Expansion blockage ⑤Too much refrigerant ⑥Circulation, high pressure interruption ⑦Condenser coil blockage
Troubleshooting:
①Replace the compressor ②Correct ③Repair the leak and refill ④Replace ⑤Remove the excess ⑥Check the airflow and fan ⑦Clean
3. The refrigerated truck unit runs for a long time or continuously
Cause analysis: ① insufficient refrigerant ② thermostat contact sticking ③ dirty condenser ④ air in the system ⑤ low compressor efficiency ⑥ blocked expansion valve ⑦ icing or clogged coil
Troubleshooting: ①repair the leak and replenish the fluid ②replace ③clean ④remove ⑤replace the compressor ⑥remove or replace ⑦defrost or clean
4. The temperature of the cargo compartment is too high
Cause Analysis:
①Refrigerant ②The thermostat setting is too high ③The expansion valve is blocked ④The compressor efficiency is low ⑤The expansion valve is set too high ⑥The pipeline is blocked
Troubleshooting: ①Repair the leak and add fluid ②Re-adjust ③Repair or replace ④Replace the compressor ⑤Lower ⑥Remove
5. Too high pressure
Cause Analysis:
①Too much refrigerant ②There is air in the system ③The condenser is blocked ④The condenser fan does not rotate ⑤The condenser fan is reversed
Troubleshooting:①Remove excess ②System vacuum ③Remove ④Check the fan motor ⑤Check the direction
6. The pressure is too low,
Cause analysis ①Insufficient refrigerant ②Compressor suction or discharge valve failure
Troubleshooting ①repair the leakage and replenish fluid ②replace the compressor
7. The refrigeration unit is noisy
Causes analysis①Lack of compressor oil ②Fixed loose
Troubleshooting ①Add oil to proper amount ②Tighten
8. The compressor loses oil
Causes analysis① Insufficient refrigerant ② Blocked expansion valve ③ Wrong oil viscosity ④ Compressor suction temperature is too high
Troubleshooting①Repair leakage and add liquid ②Remove or replace ③Use suitable oil ④Adjust the expansion valve
9. The liquid pipe is too hot
Causes analysis①Insufficient refrigerant ②Expansion valve is opened too much
Troubleshooting: ① plugging and rehydration ② adjusting expansion valve
10. The upper pipe of the condenser is cold when the unit is running
Causes analysis ① insufficient refrigerant ② low compressor efficiency
Troubleshooting ① plugging and make up fluid ② repair the compressor
11. System vacuum, only frost is formed on the expansion valve
Cause Analysis
①Ice blockage of expansion valve
②The expansion valve filter is blocked
Troubleshooting:
①Wrap the expansion valve with a hot damp cloth. If the suction pressure rises, it means there is water in the system. Replace the filter drier.
②Clean the filter screen or replace the expansion valve
