Hi all
Been using the aircon on my xf If I am driving around it works fine cooling away but if I am at a standstill It stops cooling.
I know this can be a sign of low Aircon gas so I took it in yesterday and had it refilled the guy said it needed 70 grams of gas so not low and the aircon is still the same he did say the compressor is running so has anyone got any ideas what it might be.
many thanks in advance.

 

Are the fans behind the radiator coming on when you're standing still?..If yes, then try the garden hose with a sharp spray nozzle and spray through the grille real good, you may have a bug clogged Condenser coils.

 

First off if you had to charge it, you have a leak, this is important.
Second, our Sanden PXE(16) series AC compressors are externally controlled and use NO magnetic clutch, so there is no way from the outside to tell if the compressor is, or is not running. If your mechanic used the old school way of watching the pulley for magnetic clutch engagement, our PXE16's clutch looks as if it's running ALL the time.
Third, A restriction in your cooling air flow big enough to hamper AC condenser function, would also hamper engine cooling. Also fans running or not, may or may not be due to AC functions.
Low pressure (Freon) in your AC system will cause it not to run properly, find the leak and your problem will be solved.
My(LEAKING) AC condenser , fan and fan controller were replaced last year under warr. $3000...

 

Hi thanks for the reply but I thought when they regas a system they first suck the gas out and create a vacuum so if there is a leak they would not of been able to create a vacuum to regas it sorry if I am being stupid.

 

No, you're not the stupid one.. you were perfectly correct in your assumption.

 

I think it depends how impatient the shop is. Yes they have to suck out the refrigerant and pull a vacuum as a result. If they're suspecting a leak then they would hold that vacuum for a time and note if the vacuum starts to dissipate which may take some time depending on the severity of the leak. However, once they have the vacuum there's nothing to stop them regassing it straight away...

 

All these things considered...Doesn't explain why he has normal cooling while driving down the road and no cooling at a stand still..Low refrigerant (Not Freon..only the non informed call it Freon) would not give those extremes..it would be warm or inadequate at all driving situations.

Again I'll ask ..Are your radiator fans working?...Since there is no temp gauge, so there is no way to know when the engine coolant temp is on the rise until it hits the critically hot point..the A/C system will reflect lack of air flow through the grille much sooner than if the car was to be allow to reach the overheat point..Going down the road would seem all is normal until you stopped and stood idling for a while and if no fan kicked on, then the A/C would soon show warming again..

 

This is true, but as Jaaag say's if your shop had evacuated the system (to boil out any water vapor and remove air), the leak would have shown up making it pointless to add Freon/R134 (FREON=A generic but still RELEVANT term still used by those who actually have hands on HVAC experience, and know the different uses of the various types of refrigerants dpk). Freon/R134 can be added to an AC system as a short term fix, but will eventually leak out, leaving air and moisture.

Mechanics generally quote as in "it took 70 grams" to explain what you're being billed for, not necessarily what they did..lol If they had you car for less than 2 hours I'd say they just added freon/R134.
And as far as that fan check, and hose down?
From page 1113 of the 2009-11 service manual;
"The ECM calculates the required fan speed from the engine temperature (Water and OIL), A/C (air conditioning) system pressure and
transmission fluid temperature. Under hot operating conditions, the fan may continue to operate for 4 minutes after the engine
has been switched off."
Cooling fan operation can come from more than one source, but if the fans NEVER come on (as dpk's demo might show) the AC non operation would be just an indicator, and NOT necessarily the problem.
As I said before when mine had a similar issue, Jag replaced my AC condenser, fan and fan controller to the tune of $3000