Air conditioning keeps shutting off

[Turbo Trucker]

It's gonna be over 100 degrees here real soon. For some reason my air conditioning compressor keeps shutting off. The air conditioning works good and gets cold, then all of a sudden the air starts getting warm, it's real annoying. It seems to happen mostly when I stop moving, usually if I'm on the freeway it'll stay on. Anybody else had this problem?

 

[Shovelhead]

Sounds like it's low on refrigerant. (freon, or R-134a)

 

[BCFAST]

Shovelhead is right. Your a/c system has what's called a 'low pressure switch'. If there's not enough refrigerant in the system, the line pressures get goofy and a sensor switch shuts off the compressor before damage occurs.

 

[Turbo Trucker]

Thanks! I'll have the pressure checked.

 

[Mingoglia]

My brother-in-law's half ton did that when it was new. It would be blowing cold then immediately go to warm and then cold again. I don't mean to sound like a broken record, but low refrigerent was the cause and just like someone else said, it's a safety feature that's put in to annoy you so you take it to get checked ASAP.

 

[Dfeland]

Its called short cycling which can occur if the temp in the truck is real cold or its low on freon. The low pressure switch is built in as a safety because if the compressor ran with no cold freon going back to it the it would over heat and get hot. Then all the oil would vaporize and get pumped into the evaporator and the compressor would burn up. In that respect its good that it shuts off.

 

[Lazy-Boy]

Is this something that Wadell could fix himself? Seems like I've seen refrigerant for sale at some auto part stores. Or would it be safest just to take it in?

 

[Shovelhead]

If the system uses freon, it's a trip to the dealer(unless AC certified and you can FIND some freon12, Big $$$$)



If R-134a, head to the local auto parts house, pick up a "Harry-Homeowner" set-up, a couple of cans of refrigerant, and fill it yourself.

It's easy, but... ...



READ THE DIRECTIONS FIRST.

 

[Turbo Trucker]

I had it checked at the local auto repair place, they put in some r134 it was $30 not too bad. It did shut off for a little bit but has been working good since so I'm happy for now.