Topic: Airconditioner issues

[dwight]

Hi,

   I have a 1990 LX5.0 and my airconditioner has a bad pressure switch. It's the sensor / switch that is on that tank near the firewall. It's on the low pressure side and is supposed to switch the compressor on and off as pressure changes on the low side.  This one never switches even though you can manually bypass it and watch low side pressure go from around 70 to 28. I have a new switch but want to know if there is a schrader valve under this switch. I need to know if I will just discharge the whole system as soon as I remove the switch or if the thing will stay sealed and I can just replace the switch without having to loose the system charge. Looking at the bottom of this pressure switch, it looks as if there is an actuator for a schrader type valve.. This is still an R12 system. And no I am not going to convert it as long as I still have R12 and can get it.

[70_Cougar]

You have the green light to swap out the pressure switch with no fear of blowing your charge.  Yes there is a schrader valve for that pressure switch.

BTW, R12 is the only way to go while it is still available.  If R134 keeps going up in price, it won't be that much cheaper than the prices of R12 I see.

John

[dwight]

Well, I finally got to the Mustang's air conditioner. It was the  pressure switch. Easy to change and the thing works great. Man is an R-12 system coooold! Wow. This puppy cools fast and will frost your fingers.  I have the pressure up to around 28 lbs on the low side when it pumps. When it stops it climbs up just like it always did. Seems to be doing what it should. Of course you can't find pressure verses temperature specs anywhere, but it seems to be working fine like this so I'm leaving it alone. This car has leaked about 4 ounces of freon a year since it was new in 1990. I had the O Rings replaced around 2001. No effect. I just add a little every 12 - 18 months and it seems to keep on working. I noticed that the HOnda's loose a little every couple years as well, but they are newer and use the R134. I hear they now want to ban that stuff as well. Guess the greenies won't be happy till we are all driving Fred Flintstone buggies.