The whole summer I had ac just fine, then at the end of the summer is slowly went out, now it shows it has too much freon/ pressure in system. I figure I have blockage, or a bad pressure switch. Any ideas? Where should I start?
ac problems
- Thread starter romois1
- Start date
joegr
Dedicated LVC Member
What do you mean by too much? What is the high side pressure and the low side pressure while the system is running?
(If you've only measured the low side and the compressor is not running, then you don't know anything yet. Low side pressure will be high if the compressor isn't running.)
(If you've only measured the low side and the compressor is not running, then you don't know anything yet. Low side pressure will be high if the compressor isn't running.)
The car was running with my ac on and the compressor was kicking on, I only have the low side gauge. I checked it when it was running. The pressure was extremely high so I never run my ac or defrost. I don't want to ruin my compressor.
joegr
Dedicated LVC Member
You must look at high side and low side pressure at the same time to get any idea of what is going on.
The system has protection against pressure too low or high-side pressure too high.
High low-side pressure is almost certainly not a clog problem. It could be a bad compressor or a fully open (bad) expansion valve.
You said the compressor was "kicking on." Do you mean to say that it was cycling on and off while you are checking pressure? If so, your pressure readings would be wrong. What was the pressure? Was it stable, or was the needle going up and down?
The system has protection against pressure too low or high-side pressure too high.
High low-side pressure is almost certainly not a clog problem. It could be a bad compressor or a fully open (bad) expansion valve.
You said the compressor was "kicking on." Do you mean to say that it was cycling on and off while you are checking pressure? If so, your pressure readings would be wrong. What was the pressure? Was it stable, or was the needle going up and down?
joegr
Dedicated LVC Member
Hot air as in heated air (not just uncooled air)? If so, your problem is likely to be a failed DCCV (common issue).
joegr
Dedicated LVC Member
Dual Coolant Control Valve
(By the way, you can search this site for such info.)
What exactly is the pressure reading?
Way in the red. I know this a separate problem but before if I set my auto temp at like 70 my ac would work for alittle bit then my heater would start blowing. And it would be just hot air and it won't blend at all. Is this natural.
joegr
Dedicated LVC Member
No, you probably have a bad DCCV.
"In the red" is not a pressure reading. If you're using one of those fill can gauges, then forget it. You need to post actual pressure readings to get any help. The red range of some gauge doesn't know what the outside temperature is. It doesn't know about the LS's variable displacement compressor and thermal expansion valve.
You need to address the heating problem before moving on to look at the AC. You haven't ever added any R-134a have you? (You can't accurately add refrigerant without using a high side and low side gauge set and looking up the correct pressures on the chart for the outside temperature at the time that you do it.)
joegr
Dedicated LVC Member
The system takes 28 oz. Three 12 oz cans would be too much! Also, I hope that added some compressor oil...
Still, your real problem is the DCCV (or the wiring to it, or the DATC, or one of the temperature sensors).
joegr
Dedicated LVC Member
The DCCV is the heater valve.
If aftermarket was used, it's possible that the replacement has failed already.