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Discussion Starter #1
Ok I'm cruising down the interstate, with the AC on. Slowly but surely, after a bit, it starts to blow less and less, while getting colder and colder. Finally it quits blowing at all, so I have to turn the heat on, where it slowly unthaws it until it's blowing full blast again. But I found that if I keep the AC on max, and a few notches above full cold, that it usually won't freeze up. Is this a problem with my AC system, or just the blower motor?? :confused:
 

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The problem would be your cycling switch on top of the accumulator thats the black cylinder at the firewall on the right side.To replace it just unscrew it,it has a scharder valve under it so you won't loose your freon when taking it off.You an try and see if you can adjust it first if you want to just unhook the electrical connector and you will see a screw in between the terminal blades on the switch,turn it clockwise a couple of turns and see if compressor starts cycling.
 

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Also, as with residential A/C units the two major causes of freeze up are, burnt up blower motor, and being low on r134a. Obviously his blower is working so I would guess you need a recharge.
 

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Discussion Starter #4
chuck943 said:
The problem would be your cycling switch on top of the accumulator thats the black cylinder at the firewall on the right side.To replace it just unscrew it,it has a scharder valve under it so you won't loose your freon when taking it off.You an try and see if you can adjust it first if you want to just unhook the electrical connector and you will see a screw in between the terminal blades on the switch,turn it clockwise a couple of turns and see if compressor starts cycling.
So how can a switch make the motor freeze up? Are you saying that it messes with how the compressor works, and might be making it cycle too fast?

I'll check the freon too, but I think it's done it after I recharged it before.
 

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No it has to cycle thats what is wrong,if it runs all the time it will freeze up.The cycling switch is designed to shut the compressor off when the low pressure gets down to around 25 psi then turns back on at around 45 psi.Yours is probably running all the time and never cycling.
 

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Discussion Starter #6
Thanks chuck, I'll try that out this week. That seems like a better reason for the motor freezing up than just blaming the motor itself.
 
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