WYIN : AC Components to Replace? - PeachParts Mercedes-Benz Forum

bruce.g.cameron · #1 05-20-2018, 11:39 AM

OK, gauges went on this morning. Showed absolutely no pressure, BUT compressor still not coming on.

To verify the procedure :
- I connected manifold lines to quick disconnects and manifold set. I checked that manifold knobs were closed and quick disconnects were open.
- I connected both quick disconnects to the high and low ports on car.
- I turned car on, set to max cold, AC on, and blower on high.

The gauges showed no change from when they came out of (expensive!) box.

Should they be indicating some sort of standing pressure, even with the AC compressor not cycling?

ROLLGUY · #2 05-20-2018, 11:45 AM

Quote:

Originally Posted by bruce.g.cameron

OK, gauges went on this morning. Showed absolutely no pressure, BUT compressor still not coming on.

To verify the procedure :
- I connected manifold lines to quick disconnects and manifold set. I checked that manifold knobs were closed and quick disconnects were open.
- I connected both quick disconnects to the high and low ports on car.
- I turned car on, set to max cold, AC on, and blower on high.

The gauges showed no change from when they came out of (expensive!) box.

Should they be indicating some sort of standing pressure, even with the AC compressor not cycling?

It seems that all your refrigerant has leaked out. That is "standard operating procedure" for a car with an R4 compressor and 30+ year old hoses.
Time to do what Diseasel300 has said (I agree)- check for leaks.

EDIT: Diseasel300 you are too fast for me!
EDIT #2: It was pointed out in post #14 that the vehicle has a Denso compressor, so I take back what was said about the R4 and 30+ year old hoses.