I recently recharged my air conditioner. I made sure to stay within the suggested pressures and it does work well now however it freezes up after 10-20 minutes. This gets to the point that the fan barely blows any air at all but the air is still cold. You can visably see frost building up on the ac lines and the evaporator. I have checked the evaporator drain and it does not appear to be plugged. When the ac is running I cannot hear the clutch kicking in and out however if you do it manually you can hear it. Just wondering if there are any sensors or anything else that I should check. If anyone can help with this, pictures and/or details would be appreciated.

 

Either the cycling switch is stuck closed or you have a slight undercharge.

 

Thanks for the reply, I checked my charge on the AC and it is at the rocomended level. I have ordered a cyclying switch and will be trying that. Where is the switch located I had a quick look and didn't see it. Is it right near the compressor.

 

The cycling switch will be at or near the accumulator, on or near the low pressure line from the evaporator to the accumulator.

Since you didn't specifically identify what you have, I cannot be more specific.

 

Thanks for the reply, its a 2001 Ford Escape XLT 3.0 V6. I have now changed the cycling switch and it didn't seem to make any difference. The low side AC lines still frost right up in about 10 mins and the AC itself seems to slow down after about 20 mins. I also rechecked the charge and it is up to almost the max level. Also I checked the evaporator drain and it seems to be draining well. Not sure what else it could be, any suggestions. Thanks

 

..scratches head.. How the heck do you do such a thing?


Get a manifold gauge set on there and measure your pressures under the factory-prescribed test conditions. Without pressure readings and knowing what the ambient conditions are, it isn't going to be possible to remotely diagnose...