Automotive Air Conditioning Information Forum (Archives)

Provided by

We've updated our forums!
Click here to visit the new forum

Archive Home

Search Auto AC Forum Archives

r-4 pressure relief valve, is it necessary

warrior9 on Mon June 02, 2014 12:35 PM User is offline

Year: 1991
Make: gmc
Model: suburban

I am replacing my compressor and I noticed the new compressor has a plug where the pressure relief valve would go. I removed the plug but the hole has a machined recess that fits an o-ring. the old compressor has a flat machined face for the PRV. The PRV will not screw in all the way and seal on the new compressor due to the recessed area on the mounting surface. Can I just put the plug back in and delete the PRV on the new compressor?
Thanks in advance for the help.

GM Tech on Mon June 02, 2014 2:50 PM User is offline

I believe you are referring to the high pressure cut-out switch port- the HPRV is a 3/8" threaded hole next to the switch cavity- and they were always present and never used a plug. Yes, you can run without the switch port switch- if the original was without one-- but somewhere there is a rule that with 134a converion- there must be a HPCO switch.

The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......

warrior9 on Mon June 02, 2014 5:39 PM User is offline

ok. thanks. ill get it done right then.

Back to Automotive Air Conditioning Forum

We've updated our forums!
Click here to visit the new forum

Archive Home

Copyright © 2016 Arizona Mobile Air Inc.