I just got my 2002 Volvo s0 back from the shop. It had the AC compressor replaced. I was surprised
at how much of the car depends on the operation of the AC compressor. It failed in the winter and the whole car stopped.

It is possible that when the AC compressor is replaced that all of the AC coolant could leak out?

I think that the law has changed so we can out this in ourselves instead of taking it to a service location.

Is that right? Thanks in advance.

Respectfully,

Newport_j

 

not sure what you mean when you say how the compressor failed on the whole car stopped... I suppose its possible that the AC compressor motor froze and when you try to kick on the AC and it engages the clutch you'd get some bad behavior.. In terms of your question on how the shop will handle the repair: To replace the compressor, the shop will evacuate the system to collect any R134a remaining in the system along with any remaining oil, then they will open the system up to remove the lines into the compressor. At this time its usually a good idea to also replace the expansion valve, the receiver/dryer and the various o-rings connecting the plumbing. They should also pressure test the system. At this point they'd remove the serpentine ("drive") belt and remove the AC compressor and reinstall the good unit. With all the parts reinstalled, they will then vacuum out the system (to remove all air, water, dirt etc) charge the system using a prescribed volume of oil and refridgerant. At this point the system should be working.

If you were to try this repair at home, as soon as you open up the lines to the compressor, the refridgerant will boil out and escape into the atmosphere. Fun environmental impact fact is 1 gram of R134 is the equivalent of 1300 grams of carbon to add to your footprint. Rather than buying a $5000 AC evacuation machine you can probably find a shop who will evacuate your system for under $50. Once you do your own repairs, you need to vacuum out the system (with an AC vacuum pump not a shop vac), measure and use the correct mix and amounts of R134a and AC system oil and hopefully you didn't introduce too much moisture or contaminants to your system, but with the right tools and procedures you can do your own AC work. Its important to note that the process for charging a new system is not the same as a recharge done with a kit from Autozone. Recharges don't bother to vacuum down the system.

 

Thanks for your explanation. I used to be a chemist and we went to K-Mart to get AC coolant to flush out gas chromatograph.

Then we could not. EPA and all.

Now you can get AC coolant from Wal-Mart. (Wally World)
I will have it done by a shop.

My wife was driving the car in Providence, R.I when AC compressor failed and everything stopped. It just happened.

A Volvo mech told me it was integral to the whole car. It fails and the car's engine will not start. I found it hard to believe, but now I do.

I thought that you would just be without the AC. Wrong!

Respectfully,

Newport_j

 

I suppose he meant integral in the sense that its on the drive belt and if the AC clutch fails or seizes it can take out the drive belt which also drives the power steering and alternator - and worse a torn drive belt can in some cases whip into the timing belt. If the AC clutch is functioning but the compressor or system pressure is bad, there are sensors to automatically disengage the clutch. Plus with a functioning clutch you have the option of simply turning off the AC from the dash button (note that on many cars, setting the air to defog will automatically turn on the AC to dry the air going to the windshield). Good news are AC compressors are not terribly expensive so I'd expect to be out the door for $600. What's expensive is when the AC evaporator starts to leak (common problem with 850s due to a poor water drain design) - then the whole dash comes apart and you'd be looking at $1200 or so.