Because it is a high and low temperature test chamber is an electrical and refrigeration machinery and other systems composed of equipment, therefore, once the equipment has problems, we must comprehensively check and comprehensive analysis of the whole equipment. Generally speaking, the process of analysis and judgment can be first "outside" and then "inside". Is first to exclude external factors, such as cooling water, power, etc., after completely ruled out external factors, according to the fault phenomena, was carried out on the equipment system decomposition before judging system comprehensive analysis, can find the fault with the method of backward: first of all, according to the electrical wiring diagram to find the cause of the question of whether or not to electric system, the question of whether finally for refrigeration system, Analysis tables for some common failures are provided.

(1) High and low temperature test chamber/constant temperature and humidity chamber equipment does not cool or slow cooling; 

(2) Insufficient refrigeration dose of refrigeration system (fluorine leakage); 

(3) Dirty or ice blockage occurs in the refrigeration system pipelines; 

(4) The solenoid valve supplying liquid to the evaporator is damaged; 

(5) The flow of expansion valve is too large or too small or damaged; 

(6) Check leaks and fill with fluorine; 

(7) Replace blocked devices or desiccant; 

(8) Replace the solenoid valve; 

(9) Adjust or replace the expansion valve; 

(10) high and low temperature test chamber/constant temperature and humidity chamber equipment heating slowly;

(11) The heat insurance of the heater is burned off; 

(12) The contactor controlling the heater is damaged; 

(13) Replacement of heat insurance; 

(14) Replace the contactor; 

(15) High and low temperature test chamber/constant temperature and humidity chamber system does not work; 

(16) Centrifugal fan is not running; 

(17) The fan insurance burns out, replace the insurance, the fan thermal protection, reset the protection switch;

(18) High and low temperature test chamber/constant temperature and humidity chamber compressor does not run; 

(19) the insurance of the compressor burns out; 

(20) The power supply voltage is insufficient；

(21) The contactor that controls the start of the compressor is damaged; 

(22) Replacement of insurance; 

(23) Supply voltage;