AC sometimes only blows out hot air.
05-10-2018, 08:16 PM
#1
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AC sometimes only blows out hot air. I’ve only had the vehicle for 6 months, I’ve noticed a couple of times(3?) when I turn on the car and the AC is on and blowing it only blows hot air. I click the AC on and off multiple times and nothing. I looked at my rpm gauge and I do see a difference when I click the AC on and off. I honestly can’t hear if the compressor is on or off though, I’ve yet to really inspect it.
This is what I find strange, when I turn the car off and on again the AC will work perfectly fine. Only once I turned the car off and on multiple times and it didn’t work, so I just started to drive and then it started to blow cold air.
Once the car blows cold air it stays blowing cold air.
What do u guys think?
This is what I find strange, when I turn the car off and on again the AC will work perfectly fine. Only once I turned the car off and on multiple times and it didn’t work, so I just started to drive and then it started to blow cold air.
Once the car blows cold air it stays blowing cold air.
What do u guys think?
05-11-2018, 07:18 PM
#3
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iTrader: (3)
Could be a number of things such as an over charged system, an under charged system, a faulty compressor, pressure switch or faulty connector. Having the A/C gauges can rule out whether it is over charged or under charged.
05-14-2018, 11:27 AM
#4
WHAT VEHICLE DO YOU OWN? If its a 99-02 Camaro Firebird Could be ALOT of things but the 1st thing I would check in this case is the output from the HVAC controller to the PCM. When you move the control to AC it sends a request signal to the PCM to start the ac compressor. Its very possible your controller is not sending a request signal to the PCM at times. Once the PCM gets the request for AC it then checks the system pressures via the pressure transducer in the AC system. If the signal from the transducer is within the proper parameters the PCM turns on the relay that controls the compressor. If the relay is good the compressor comes on and the PCM monitors the operation using the pressure transducer. Its also possible the pressure transducer is faulty or the compressor relay is faulty. Sometimes the compressor clutch assembly can be faulty also. There are NO pressure "SWITCHES" in your system as suggested above. Trust me I've been doing AC repairs professionally for 30+ years.
Last edited by RockinWs6; 05-14-2018 at 11:40 AM.
05-14-2018, 03:49 PM
#5
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iTrader: (3)
I didn't know the actual name for it and was corrected from another member in another thread but I was referring to the transducer. And for those who need more clarification as to what a transducer looks like here you go!
05-14-2018, 03:50 PM
#6
11 Second Club
iTrader: (3)
05-14-2018, 09:35 PM
#7
All it does is output a signal voltage the PCM uses to monitor the system pressure. The actual switching of the compressor on or off is done by the PCM through the compressor relay. These systems run the compressor at all times unless there is a problem like pressure too high or too low. The compressor has a built in auto throttling valve that controls how much refrigerant is pumped through the system.
