Hello to all,

I have a new to me 1995 Volvo 940 which I love. I have a questions regarding the AC. The previous owner let me know there was a leak and he would refill it using AC pro when the level got low. Over the period of a few weeks the AC got warmer. At this point the compressor is not kicking on at all and it is blowing warm air. A couple of questions:


1) is it possible to refill the refrigerant with the compressor not running? I have read it is possible the coolant is so low the compressor will not turn on.


2) How can I "Jump Start" the compressor long enough to get a reading on my refrigerant level and refill if needed?


I really appreciate your resonse

 

Here ya go, from Volvo tips: https://www.volvoclub.org.uk/faq/Hea...rClutchCycling

"Quick A/C Fluid Diagnosis. [Editor] To determine whether your poor a/c is due to low Freon, start the engine and turn a/c and the fan to "on" . Open the hood. Locate the receiver dryer (the big aluminum can up near the firewall on the passenger side in LHD cars. Push the spring clip on the low pressure switch connector, mounted on the side of the dryer, and remove the connector. Using a paper clip, short the two connectors. If the compressor engages, your Freon is low."

 

Thank you very much for your reply. I was able to get the clutch to engage for a short time by inserting a paper clip in the low pressure switch. Unfortunately I pulled the paper clip and was not able to get it to engage again so was not able to refill using the refrigerant that I have.

At this point, do you have any suggestions on the next step? It does seem the refrigerant is low. Unfortunately I cannot refill without the compressor running. Is jumping the compressor with a wire to the battery an option in order to get it to operate long enough to refill?

Thank you for all of the assistance

 

Make a jumper wire with a 1/4" male spade terminal on each end. Plug that in to the connector from the receiver / drier. Start the car and the compressor clutch should engage . If it doesn't then the compressor clutch or the compressor is shot.

 

I would first check you didn't blow any fuses and that there's power to the low pressure switch. If that checks out ok then consider the compressor.

 

Moe,
Sure enough the 30 amp fuse for the blower was blown. I was able to get the ac compressor and clutch to engage while on low. When I turned it on high the clutch disengaged. So I turned it back to low and was able to check to refrigerant. It was low, I added a 12 oz can and it was still low. I will look into getting another can tomorrow.

It was interesting to me the clutch engages on low but not on the higher speed. I know I need a new blower motor resistor since it only blows on high. I am not sure if this would in any way affect the compressor not running. I am hoping by getting the refrigerant to an acceptable range it will blow cold with the fan on high.

Thank you all for the insight...