Air Con Compressor - engaging

Hi guys;

I had my aircon compressor replaced and the full system serviced on my 1998 Jeep Cherokee ; 4.0 Liter petrol.

The aircon worked ok for the first few weeks( i drive it only on week ends).From day 1 there as a squeeling/squeeking noise.I took it to the shop to make sure its nothing mechanical like the bearings of the reconditioned compressor.They informed me it is theh belt and plan to replace it soon.However during this week-end the air con did not cool the vehicle.With the aircon switched on ,I noticed that the compressor did not engage.On closer inspection it seem to struggle to turn.It turns a few revolutions and stops and battles again.All this whiilst the egine is running and the air con switch is on.

I would appreciate any comments and thoughts on what the problem is.

The compressor has a 12 month guarantee and i plan to take it back to the shop.

I would like to have a better understanding of the problem before i take the jeep back to them

all suggestions will be appreciated.

regards
collin

In the U.S. we abbreviate Air Conditioning as "AC", not that your way is wrong, just so you know what we are talking about, because likely all the responses you read will talk about "AC".

2 basic things are happening here, either:

*Pressure is building too high in the system and the force required to turn the compressor is too great, thus it stops and the belt slips.

OR

*The belt is too loose and slipping on anything requiring extra force.

Maybe a combination of both, I've had a mini-van where the perfectly fine compressor was seizing from the AC pressure being too high for the belt to drive it, it caused the motor to stall at idle with the AC on, the compressor dragged the engine down so far.

You need to have a gauge set put on the AC so you can tell what is really going on inside the system. It can't hurt to check the tension of the belt, and tighten if its too low.

Sometimes its just a bad pressure switch or relay that prevents the fan from turning on, the AC overheats and for AC that means the Hi-Side pressure soars, and causes the whole system not to work and seizes/stalls the compressor. The electric fan should turn on within seconds of turning on the AC, even at the lowest settings, if that fan is NOT turning on, that is likely your problem and its likely a pressure switch or relay that is causing the problem.

Take it back and have them troubleshoot, hopefully it will only be a $8 pressure switch they swap out and everything works fine. Unfortunately with AC, it could be something serious and expensive also, if thats the case, hopefully it is covered under warranty for the work done previously.

? for ya Rick,sorry to semi-hijack thread but this is killing me to no end trying this figure this out,When i turn my AC on, the fan will kick on ,but the clutch will not engage.I just ordered an AC clutch relay hoping that would be the culprit.Thanks for any advice