ASE A7 Exam: Questions & Answers (Heating Air
Conditioning): ASE A7 Heating Air Conditioning
The compressor is rapidly cycling on and off on a CCOT air conditioning
system. Technician A says this condition can be caused by a low
refrigerant charge. Technician B says this could be caused by a faulty
clutch cycling switch. Who is correct?
(Ans- Both technicians are correct.
Technician A says while performing a retrofit from R-12 refrigerant to
R134a refrigerant, the refrigerant must be recovered into a dedicated
cylinder, they cannot be mixed. Technician B says R-12 refrigerant
functions at higher pressures than R-134a refrigerant does. Who is
correct?
(Ans- TECH A is correct. The two refrigerants cannot be mixed. A
separate, dedicated R-12 refrigerant container is used. Each refrigerant
has its own color assignment. R-12's assignment is white and R-134a is
sky blue "light blue".
Technician A says an ambient temperature sensor senses cabin air
temperature. Technician B says a faulty ambient temperature sensor
can prevent compressor clutch engagement. Who is correct?
(Ans- TECH B is correct. The automatic temperature control module
uses several input sensors. The ambient or outside air temperature
sensor is a variable resister. If the outside temperature is colder than