Question about Air Conditioner
 

My high pressure switch has to be replaced. If I remove the high pressure switch will the freon leak out to atmosphere, or is there a schrader valve on the high side line at the switch. See photo. Thanks.

I "believe" there is a schader valve in the fitting.

But, you can just unplug the connector and put a jumper in it, and by-pass the switch. I ran mine like that for 3 years.

It is a safety device to shut off the compressor if the pressure gets too high (which is really high).

But there is also a "solder plug" in the dryer that will blow out if the pressure gets that high anyway.

Thanks. I thought of that but unfortunately the switch that does not work is the high pressure switch not the dual pressure. The high pressure switch activates the condenser fans when the pressure goes above 220psi. The normal high range on the ac is about 213psi. Bottom line is that when I have my ac on and the car idles at a light the condenser fans do not turn on. Heat starts to build up on the condenser and the pressure starts to build up real high and the cooling inside the car starts to drop. I checked the condenser fan circuit and it does work. I can switch or ground the high pressure switch and fire up the fans. I can do the same with the high temp switch on the thermo housing. Personally I would just probably put in a switch and fire it up at idle like you suggested but my wife drives the car occasionally. I would hate to remove that switch with no schrader valve and lose all my expensive r12. See the photos.

ok ... yes this is off the subject
 

this is a lil strange but i think i have your twinhttp://www.toyota-supra.info/forums/...attach/jpg.gif

Well, I can understand when someone else drives the car, which I never allow. But I don't know if there is a schrader valve in there or not. Perhaps someone who has removed their ac system can check those fittings for you.

I know what you mean about others driving the car. I tell my wife the only important gauge to watch is the temp gauge. I figure a total failure of oil pressure would be rare.

On the switch note here is a picture of the switch. The part the screws into the high pressure line. Does not look like there would be a pin or other mechanism that would push on a schrader valve. Take a look.. See what you think.

what? Your car's are totally different:confused:

Still looking for a ac shop that reclaims or recovers r12. One guy told me I should change out the receiver / dryer if I am going to evacuate the system. He states it is very inexpensive and it acts as a filter for impurities and removes moisture from the system as well as a reservoir. My system cools very well although it is a tad low on freon and has not been opened to air since 1991. Any thoughts. I hate to fix things that are not broken.

Yes.. Delete it and gain a 10th of a second.

Best mod I ever did.

If the ac is working, and cold, and just a bit low on freon, leave it alone.

The receiver/dryer should only by replaced when the system needs to be opened, like fixing a broken hose.

"Don't Mess
With Success"