I had a fault with the compressor on the Volvo & after a number of quotes & some prety shady advice I decided to research the fault myself & have a go @ fixing it
It took me 3hrs, a home made puller & no materials or costs
The fault was as follows, it would work fine for 1 or 2 minutes then stop & work no more
When working it would occasionally make a clattering/chattering type noise
What it was was the air gap on the magnetic clutch had become to large & so it would pull in giving drive when the coil was cold but once warm would fail
The air gap should be something like (don't quote me) 0.6 to 0.8mm & mine was something like 1.2mm
Remedy was to remove the front pulley, remove one of the already fitted shims to bring the clutch air gap back into tolerence, bolt the pulley back on & bobs your uncle
No need to remove pump, pipes or have a regass
Worth a check Id've thought