that I couldn't say for sure. I'd expect a pressure switch to be in contact with the AC refrigerant, so yeah, pulling it would require first vacuuming out your R-whatever, then replace it, then pump a vacuum and replace the refrigerant.

 

Alright. Thanks!

 

Got it replaced. Just for future reference, there's a protective valve that keeps refrigerant from leaking when the switch is removed. Works well now!

 

^^^ It is called a schrader valve but the one on my car doesn't seem to work.

 

Ah... It did spray a little when he took the switch off. What does yours do?

 

Mine just never seals so it will continue to leak until the system is empty.

 

That's awful!

 

I just got a 93 240 and when I turn the air conditioning on, the clutch in the compressor will engage and then quit immediately, what could be the cause for this? I am new to Volvo 240s, thanks

 

too little or too much pressure in the system, most likely. its very basic air conditioning, an on/off signal comes from the A/C thermostat switch in the dash, this goes through two 'pressurestats', one on the reciever/dryer 'can' near the firewall, and the other on the condensor manifold at the bottom of the radiator. one pressure stat is high pressure, the other is low pressure, if either one triggers, it disables the compressor.

 

what it does was it engages and disengages immediately, it does that again and again., does this mean that I need to recharge the system, or air conditioning service?

 

you hook an a/c pressure gauge up and test the system. if its low, it probably should be evacuated, leak tested, and charged. I take mine to a mechanic with an a/c rig. if its low, its probably leaking slowly, its a good idea to put some UV dye in with the freon, then you can inspect under the hood with a UV light and see where its leaking.

 

Thanks a million Pierce, I will have it serviced, what a relief, I was thinking a bad compressor.

 

So, air conditioning is not that hard. If you ever took a canned of that compressed computer dust cleaner, tipped it upside down and sprayed it; you'll note that the air is really cold. Due to the nature of the gas when under pressure and suddenly able to expand, it creates a cooling effect. With Freon, and I believe some variant of alcohol (the old 1920s fridges used this until it was deemed too dangerous). You apply heat and pressure on one and of a tube and on the other you get cold. In essence, you're moving heat.

To make freon more efficient, we compress it, much like that spray can, the compressor puts the gas under pressure and releases it into the evaporator where the cabin fan blows nice cold air. The gas goes back into the low pressure plumbing and into the condenser, in front of your radiator.

In 1994, DuPont's Patent on Freon ran out, they actually helped lobbyists rail against outlawing the old gas. The new freon gas, all it has is a few extra hydrogen molecules that enables it to become more viscous, water/oil like instead of gas, thus settling to the ground instead of evaporating into the air.

With this in mind, any HEALTHY current A/C compressor can be converted. It needs to be lubricated, o rings need to be replaced. However, there's no reason why any system cannot be repaired and/or retrofitted for new freon.