First Day of Summer - AC Woes

[tankowner]

Originally Posted by upallnight

System pressure is NOT the correct way to recharge an AC system. The correct way is to remove all the refrigerant from the system and refill base on the the weight of refrigerant as measured with a digital scale. That is why there is no BMW specification for system pressure.

Yeah, understood, but it seems like most manufactures provide a range of low and high pressures under which the system can be assumed to be functioning properly given the correct mass of refrigerant is present in the system and adjusting for ambient temps. Knowing some baseline pressures would also help diagnose problems when they arise.

If BMW doesn't provide pressure specs, do you happen to know the mass of the refrigerant to be added?

Thanks again.

[Zulu95]

Given that the system only requires a small charge from empty I would think the amateur can with a needle approach is not the best for a long term fix. I did it once to give me cool air on both sides until a professional work through could be arranged.
It started with the cooler on the driver's side but after a few days ended with blowing ice on the drivers side until it completely iced up and no air would come out until it thawed. A quick squirt can got me AC on both sides and the indy then ran the complete discharge/recharge/troubleshoot process.

[upallnight]

System pressure varies with outside temperature as well as the speed the compressor is turning.

By Mass I am assuming you want to know how much refrigerant by weight that the system should have in order for it to perform as designed.

The refrigerant weight for a 1999 to 2005 X5 should be 440 grams +/- 15 grams. 440 grams is approx 15.52 ounce or close to a pound of refrigerant.

[tankowner]

Originally Posted by upallnight

There are mixing valves for the heater core and perhaps one of the heating valves is not closing. Do you have the auto or manual climate control panel?

Following up on this thought - are there known problems with one or the other type that has been known to lead to problems with the mixing valves?

Originally Posted by upallnight

System pressure varies with outside temperature as well as the speed the compressor is turning.

By Mass I am assuming you want to know how much refrigerant by weight that the system should have in order for it to perform as designed.

The refrigerant weight for a 1999 to 2005 X5 should be 440 grams +/- 15 grams. 440 grams is approx 15.52 ounce or close to a pound of refrigerant.

Great. Thanks for the information. Appreciate the help!

[upallnight]

Originally Posted by tankowner

Following up on this thought - are there known problems with one or the other type that has been known to lead to problems with the mixing valves?

Great. Thanks for the information. Appreciate the help!

Plenty of Youtube videos on BMW heater control valves, how to test them and how to rebuild them.