A/C could use a tune-up, I think

[BritCarFan]

Hello all,

With the 90 degree weather approaching, I think it's time to do a tune-up on the A/C system. It seems to blow cool but not cold. Anybody got any thoughts on this

 

[healeynut]

sounds like it's time for a recharge on the AC coolant. Just take it to your mechanic, should be a quick fix.

 

[Exotexs]

are you referring to the Jaguar? Start by checking the gas.
R-134a I suppose? It is not exceptionally cold, that is everybody's complaint. I love R12.

 

[maynard]

Sounds like the car needs some refrigerant added. As a 93, it could be either R12 or R134. You can tell by the fittings. If they look like tire valves, R12, if they are bigger, without threads on the outside, they are R134. If it is R134, you can try adding a can yourself. If the car has a sight glass, just add R134 until the bubbles disappear. If it is R12, you need a shop to top it off, since R12 can only be sold to a licensed tech.

Exotexs-I have to disagree. If a R134 system is properly designed and operating properly, it is as cold as R12. In my 94 XJS, on a 95 degree day, I get 0 degree F air our of my vents. Last week, on a 91 degree day, my glasses iced (not steamed) up when I left the car.

The problem occurs when a system is converted from R12, Depending on the car, you may need a different expansion valve, orifice tube or H valve. Most shops don't do a complete conversion because of the difficulty (the aluminum fittings often corrode and strip out) or because they can get adequate (not optimum) results without doing it.

 

[Exotexs]

Maynard, you said it: "If a R134 system is properly designed and operating properly, it is as cold as R12"

but they never operate properly do they?, especially if it's a conversion. Personally, I don't like R134a, (I won't use it in my cars), in any case I would use an alternative refrigerant like "Freeze12" or others. But R12 is still available, and as long as it is, there's no better, it is the automotive refrigerant to which all others are compared, as you just said: "as cold as R12".

Ex

 

[BritCarFan]

The Jaguar uses the R134 coolant, but it does not have the sight glass. I guess there must be a certain pressure needed in the system.

 

[DrEntropy]

Manifold gauges and refrigerant. You MAY get away with squirting more in the system with one of those "kits", but it'd be best to have someone with a set of gauges check the pressures in case you've a problem within the system.