AC Pressure Relief Valve woes

[heuster]

This is a LONG story that I'm going to try and cut short.
Last week I blew out all lines with air and solvent(front and rear evap, all lines to/from rear)
Put in a new fan clutch (aftermarket brand)
Followed that up with vacuum test - all good
Filled with 60oz and 8oz of oil(assumed that there was 1.5 in compressor and 1.5 in condenser)
COLD AS ICE.
3 days in use, it was 88 degrees and I'm sitting in the cul-de-sac waiting to pull into my garage and the pressure relief valve starts blowing refrigerant

Not that this is totally relevant, but this behavior has happened before. Prior to all that I described above the compressor grenaded and I followed that up with a complete rebuild of the system. (all new components top to bottom) and after I got everything up and running, the pressure relief valve started doing the same thing. So I evaluated everything, then the tranny went bad and it sat for 3 years. New R&R on the tranny, new dryer, and start over with my opening "Last week I blew out all the lines..."

Could this just be an issue where the fan clutch is not cooling enough because it's aftermarket? Could there be a blockage in the condenser somehow? Faulty expansion valve? It's hard to reproduce...it doesn't always happen the same way every time, but it always stops as soon as I turn off the A/C.

 

[Hamfisted]

What's your low and high pressure on the AC system ? You could just be overfilling it. Shoot for 40-45 degrees out of the center vents.




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[heuster]

What's your low and high pressure on the AC system ? You could just be overfilling it. Shoot for 40-45 degrees out of the center vents.




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Temp was reading 50 degrees. Can't go wrong on the math. The system calls for 62oz when empty and I only put 60 in it.

 

[Hamfisted]

Did you use a new condenser and put a good vacuum on the system ?

 

[heuster]

Did you use a new condenser and put a good vacuum on the system ?

did not use a new condenser and vacuum looked good and checked out great. If the condenser had a blockage, wouldn't it be blowing freon all the time? Usually when something like that happens doesn't the system work fine, it just doesn't get cold?

 

[heuster]

Any ideas on this? I am just not coming up with anything anywhere I look. I could start throwing money at it and replace the condenser and refill, then replace the compressor and refill...that's over 100$ worth of freon

 

[heuster]

Could really use some more ideas from anyone that is familiar with AC troubleshooting. I do have a couple videos I took, but the refrigerant level was a bit low from losing freon out the pressure relief valuve. Blew cold, around 60 degrees and didn't blow any freon while sitting in the garage idling for about 20 minutes.

 

[JamaicaJoe]

The above might give you an idea if there is too much refrigerant in the system. You might want to open all doors and run the AC fan to circulate ambient temperatures through the system. Note this is static pressure when the system is off, no suction on the low side so it will be higher than when system is running. Use a thermometer to get your ambient .

 

[heuster]

The above might give you an idea if there is too much refrigerant in the system. You might want to open all doors and run the AC fan to circulate ambient temperatures through the system. Note this is static pressure when the system is off, no suction on the low side so it will be higher than when system is running. Use a thermometer to get your ambient .

So the challenge I have with this is that I haven't added any refrigerant into the system since it started blowing freon out the first time and I was driving it the other day and it just started blowing freon again, even when it's on the low side already. How does that make any sense?

 

[JamaicaJoe]

Expansion valve getting blocked? Condensor coil dirty? Fan blade not turning?