AC Auto experts please step in...I have a question.

[A.Barrett]

Not unusual depending on refrigerant levels. is it staying cool, or still getting warm / hot air after a few minutes?

If you are still having trouble - at least have a shop test the high and low side (refrigerant levels), and if they are normal, you may have a blend door (or blend door actuator) issue (causes heater to leak hot air into the system as car warms up which = warm air at vents).

 

[Shey]

2015 Subaru Forester. 188K. Great shape. AC was checked out recently- evacuated and refilled and the shop gave me a clean bill of health. I took it in because the former owners said it would blow cold, then stop blowing cold. Shop said I had a clogged air cabin filter, It blew cold leaving the shop. Now it does not blow cold after a while.

Do I have a bad compressor? If not, what else could it be?

@41mag

This doesn't make sense for the shop. Issue shop diagnosed: cabin filter was clogged. This would affect airflow, not changes in temp as former owners stated. Evac and refill: a properly working system should never need evac and refill, what was the reasoning behind this service? Especially after giving A Clean Bill of Health.

 

[Nathaniel Brown]

Need to know several things in order to diagnose. Is the compressor clutch engaged when it stops blowing cold? If not engaged, is it still receiving power? If not receiving power, are pressure switches in open or closed position? When working correctly, need to compare high and low pressures to a chart and make sure they match what's called for at ambient temperature. If it works sometimes and not other times, I doubt it's a leak. I use nitrogen to find leaks. Dye takes too long. Slam 300psi of nitrogen in the system and the leak will identify itself real quick..... My guess is that it's the compressor clutch. It is an electromagnetic clutch. Magnets get weak when hot. Over time, the clutch wears and the gaps gets larger. Once the gap gets too large, the magnet can't close it while hot. Once it gets cool, it can close the gap for awhile, till it heats up again.