Hello Don Emmett,
I suppose this would be a really great time to ask...
cannot offer an intelligent answer with
being the all knowing... all seeing (blah blah blah)...
Year, make & model
Sadly for you... I'm the second twin ... which OFFICIALY makes me "the other
" (as opposed to the "one
" mentioned before...
I seldom even wait for questions to be completed... before starting my answers.
Year, make & model
...does matter (just not much)...
Somewhere in the last couple of decades... automotive
engineers felt they could add a level of reliability
by adding pressure switches... This keeps the COMPRESSORS from POINTLESSLY OPERATING without any REFRIGERANT in the system
(low pressure = escaped refrigerant)
Refrigerant gets away sometimes because the "condenser"
(typically in front of the RADIATOR)... got hit by a "road hazard"
and now has a nice leak... or more likely THE INPUT SHAFT SEAL on your COMPRESSOR is worn... (oil shows... behind the clutch... (on your otherwise spotless engine (little oily dirt line inside the hood (too))). My money is on the FRONT SEAL
Fix it... Gambling will only get you another season or two
but will likely result in an ENTIRE pump replacement.
If you are half psychic you might want to gamble or guess
how much oil got away... there are ways to add oil without opening the system)... After this point there is more begetting & begetting than the old testament.
Run without enough oil... lose the compressor + condenser + dryer. Put in the wrong oil or in-compatible REFRIGERANT...
gum up the system...
Just fix it... Seals are cheap...
If it WAS a FREON 22 system it is long past needing an update.
California ... it is a CAPITAL CRIME to even speak of refrigerant...
Unless you are in the Mojave (did you ever notice how quiet everybody gets above 115 degrees?)...
I'm just saying
Disclose what refrigerant you are using... in which car... the age of the car... Bullet holes, raccoons living under hood? Oil all over the compressor... and I can speculate if shorting the pressure switch will cause the clutch to engage... or blow up the compressor.
My best guess YOUR REFRIGERANT IS LOW
Share a couple of details... I'm sure I can help.
2000 CHEVROLET TAHOE 5 3L V8 Compressor RockAuto
Amazon com HVAC Single stage Rotary Vane Vacuum Pump 3CFM 1 4HP...