A/C compressor runs on heat and a/c

[Urquattro]

On my '87 260e, the A/C has plenty of freon and the compressor works, but the air will not get cold. Or hot. No matter what temperature I set the "temperature wheel" to, the A/C compressor will stay on. The air blowing out of the vents is not HOT like on heat, but its not being cooled either. So I switched out the pushbutton unit, figuring it was bad, and it's still doing the same thing.

Any ideas? Bad Klima relay perhaps?

[Urquattro]

Update, took the cover off the Klima relay...nothing really looked out of place (burned/cracked/etc)

[Chas H]

Is the return line to the compressor cold?

[Urquattro]

Not sure exactly which one is the return line, but the "lower" line that goes to the bottom near the compressor is hot, and the "upper" line shows no change in temp(not hot or cold)

[Chas H]

The return line is the larger, upper line. If it's not cold there is a low charge in the system or a blockage somewhere.

[Urquattro]

Must be a blockage somewhere then.. Was hoping it was something not so in-depth.

[Chas H]

Originally Posted by Urquattro

Must be a blockage somewhere then.. Was hoping it was something not so in-depth.

Yeah, don't we all. You prolly need to visit the A/C specialist.

[saumil]

Is it possible that you have a leaking monovalve, so the heat exchanger is compensating for your a/c. What is the voltage on the monovalve when your car is set to a/c ?

[brewtoo]

You say the AC has "plenty of freon." Can you define that?