When we use the temperature humidity test chamber probably we will meet a problem: temperature can't cool down. 

Here I will list some methods to deal with this problem. 

1.The temperature didn’t cool down.

1) Cool the environment temperature down to 5℃～28℃.

2) The air cooled condenser use for a long time, the dust accumulates too much, clear the dust on the condenser is OK. (Could use compressed air gun)

3) Check the value of refrigeration pressure gauze, static pressure generally will in 6kg (or 90 psi inside the pressure gauze), if lower than that, probably will appear the problem for refrigerant leaking and cause the refrigerant is not enough, need to check the refrigeration system.

4) Use multi meter to check if the solid-state relay strike through or not. Finally, to cause the heating pipe is working always,and offset the refrigeration of compressor, so don’t cool down.

5) Refrigeration solenoid valve didn’t open. Use multi meter to check resistance value.

2.The temperature cooling rate is very slow.

1) The chamber door isn’t close well, and the fan didn’t rotate.

2) The active load is very large.

3) The test specimen inside the chamber is too much(normally situation, the test specimen is less than 1/3 of the chamber),finally to cause the fan can’t circulate.

4) Check the solution of the temperature didn’t cool down.