QuestionMy 1998 Dodge durango(v8 318 155.000 Miles)ac works fine for short time. Then the air flow slows down and ac is not cold. Turn off the ac and wait for short time (15-20 mins.)Turn ac back on blows cold for a short time. Then starts same problem all over. Any ideas on what the problem is?
Thank you for your time and help.
Answerthe evaporator is freezing up
EXPANSION VALVE
FRONT
The front "H" valve-type thermal expansion valve (TXV) is located at the dash panel between the liquid and suction lines, and the evaporator coil. High-pressure, high temperature liquid refrigerant from the liquid line passes through the expansion valve orifice, converting it into a low-pressure, low-temperature mixture of liquid and gas before it enters the evaporator coil.
A temperature sensor in the expansion valve control head monitors the temperature of the refrigerant leaving the evaporator coil through the suction line, and adjusts the orifice size at the liquid line to let the proper amount of refrigerant into the evaporator coil to meet the vehicle cooling requirements. Controlling the refrigerant flow through the evaporator ensures that none of the refrigerant leaving the evaporator is still in a liquid state, which could damage the compressor.
The expansion valve is a factory calibrated unit and cannot be adjusted or repaired. If faulty or damaged, the expansion valve must be replaced.
