Air Con: 70: Windscreen defrost failure

[gandalfs]

Hi all, I am a new member: I have a V70 petrol 20v 5 cylinder R reg (1996-97 I believe) I had an engine management light come on which was diagnosed as a faulty E.C.T. Sensor & Thermostat fault. Whilst waiting for repairs the Air-Con switchlight, which comes on when the screen defrost knob is selected stopped lighting-up: also the re-circulation switch light stopped working. The weather has been very cold and no heated air or come to that cold air either is reaching the windscreen. The E.C.T. Sensor & Thermostat have been replaced and test ok. The Air-Con still not coming on at defrost setting nor if manually selected, no air getting to the windscreen the cabin settings are blowing warm air though. Appologies for length of posting, garage mechanic thinks electrical issue and needs the car for couple of days to diagnose and order parts if required.
best regards
gandalfs

[andycallaghan]

I trust you know that it's a demister, not a de-icer. You will only get warm air when the engines warm also.

But I guess what your problem is is that when the car is warmed, all vents except the screen blow warm? Am I correct?

[gandalfs]

Hi Andy, yes I had warm / hot air out of all vents except the screen vents: recently had itlooked at by a volvo engineer who removed the control panel checked live & earths, could not find any problems! refitted the control panel and all ok? Anyway since then windscreen demist ok...

Engineer said the aircon compressor badly corroded and cost of new £300+ plus fitting say total £500.

Why are they so expensive?

thanks for the reply.
regards
michael

[liuleichan]

Originally Posted by gandalfs

Hi Andy, yes I had warm / hot air out of all vents except the screen vents: recently had itlooked at by a volvo engineer who removed the control panel checked live & earths, could not find any problems! refitted the control panel and all ok? Anyway since then windscreen demist ok...

Engineer said the aircon compressor badly corroded and cost of new £300+ plus fitting say total £500.

Why are they so expensive?

thanks for the reply.
regards
michael

Brand new compressors may be expensive - but new ones seem to be cheaper than that on ebay.

Plus you could always take a punt on a used one. I bought one from ebay for £20, reshimmed it, it's been on my car for months, working perfectly.

[jaytee]

It may be that the actuator motor for the flap that sends all the warm air to the screen vents is faulty or seized. Or it may need reset, having got out of sync? There are five motors/flaps in the heater box.

Jim