07 XC70 driver's side blows warm air with A/C on Topic is solved

[erikv11]

Low on charge.

If you had posted this right away ...

[abscate]

Is it peculiar that the static pressure (engine running, AC not running) readings are not the same on low (65 PSI) and high (100 PSI) side? Seem too far apart to just reflect gauge (in)accuracy.

The high/low temperatures are different, so vapor pressure is different. But high side will eventually boil off and expand to the low side if left undisturbed.

The static low side pressure is useless as a diagnostic as it depends on how much Freon gets stuck in that part. It slowly equilibriums over hours/days? So many people have screwed up their charges putting on a cheap can gauge and making a static measurement for guidance.

Final ration about 5:1 high/Low?

How is the temp delta , aim for 35F between ambient and center dash output

[vtl]

The static low side pressure is useless as a diagnostic as it depends on how much Freon gets stuck in that part. It slowly equilibriums over hours/days?

Yes, low side will have a saturated vapor pressure until the last liquid drop is gone. It only dips below that pressure when A/C compressor is cycling and the system is almost empty.

Stabilized over night in my case.

[erikv11]

…
How is the temp delta , aim for 35F between ambient and center dash output

No means to measure this, available technology is shown in that image on the previous page! But SWMBO reports “that AC is icy now” so objective one has been achieved.

[vtl]

But SWMBO reports “that AC is icy now” so objective one has been achieved.

[yanga001]

Just wanted to add my experience.

My 08 S60 did the exact same behavior when low on AC charge. I verified it through a mixture of monitoring the charge at rpm's and by checking the evaporator temperature as monitored through my code scanner. Getting the evap temp down below 4C is what usually tells me it is working properly.

I get about 10 days per half can and cans are 5$ each for R12A. The dye seems to be leaking by the condenser near the radiator. One day i may change it but that day is not soon.

[br0dy519]

MVS correct diagnosis : two hours
OP’s acceptance of diagnosis : 1 month

I feel like each day I get older, the JRL inside of me wants to be let out of the cage. RIP

[abscate]

MVS correct diagnosis : two hours
OP’s acceptance of diagnosis : 1 month

I feel like each day I get older, the JRL inside of me wants to be let out of the cage. RIP

To be fair, most of us take a month to cycle back to work on Car time, especially for stuff thst doesn’t impact going to work

[erikv11]

Yeah in the intervening month the car went on some very long (for us) road trips, logged about 2,000 miles, but AC performance was acceptable. It did still take me two days once I actually worked on it, but at least I know more about the system now.

Echo the nod to JRL!

[vtl]

I get about 10 days per half can and cans are 5$ each for R12A. The dye seems to be leaking by the condenser near the radiator. One day i may change it but that day is not soon.

Correct refrigerant is R134a. Also most of cans come with oil. If you top up your A/C system that often, you'll eventually add more oil than it can take if you use such cans. I buy dry refrigerant specifically (no oil) and add oil separately, depending on which A/C part has been replaced.