The whole design of the air conditioning system on the '89 240 is that the evaporator outlet pipe temperature is sensed and will control when the electro-magnetic clutch on the ac compressor is engaged/dis-engaged. My question is this...what will happen if the outlet pipe temperature never gets cold enough to cycle the clutch off? Will the clutch coil magnet care? On the other hand, too frequent cycling will definately damage the coil because it's being energized and de-energized too frequently. My question is also this: on the '92s and '93 volvos...they replaced the A/C knob (the blue red adjustable one) with the "on-off" switch. Does this mean that the newer systems maintain the clutch engaged "more" than the older system?

Two questions: 1) What will happen if the outlet pipe temp never gets cold enough to cycle the clutch off? (especially w/ R134 temps) and 2) Do the newer 240 volvos ('92 and '93) "on-off" design keep the clutch coil magnet energized more?

Cabbie2169