I just refilled with R134 after putting in some sealer and the rapid cycling stopped. I guess that's a good thing. So why does the compressor cycle rapidly when the refridgerant is low?

I sure hopes this patch up job works.

There is a low pressure switch (called a "pressostat") that will shut off the compressure if the pressure drops too low. This is to prevent damage due to the system drawing air w/moisture into the system.

Don't want to scare you but refilling the R134 could be just a temp. fix. The evaporators are known for developing leaks on the 850. I've had mine replaced once already while the car was still under warranty. I might be due for another one seeing that I refilled the R134 just last year at around this time and it is very low again.

If it's any consolation Volvo isn't the only manufacturer with a high evap mortality rate. I understand that Chrysler is affected also. Now my wife's Dodge Caravan has lost all of it's R-134. I put two cans in and it's working again but I realize this is temporary.

I bought my '95 855t knowing about the evap issues and that most owners here on the board just recharge annually.

The way I look at it is; If I'm possibly facing an evap replacement down the road, I'd rather be driving my turbo wagon than an Intrepid.
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Happy Motoring, Erwin in Memphis, '95855t

I agree. My car is way out of warranty so I only plan on spending the 40 or 50 bucks a year to re-charge the A/C. Better than shelling out the thousand or so only to have it leak again in a few (at best) years.

Compressor cycles because of loss of pressure....

95% chance - hole in evap. core.