AC advice needed

[Mark]

My AC is not blowing cold air. The compressor cycles fairly rapidly at idle. The inlet to the evaporator is cold, but the outlet is warm. According to my FP gauge I have 76 psi at the accumulator with the AC off. Is this an orifice problem? Is there any way to avoid evacuating the system? I still have R12 in the system and would like to avoid switching to 134.

Thanks,
Mark

 

[49-blues]

whats the pressure with the ac on?does the compressor short cycle? clutch engages and then disengages?if so your short on refrigerant.

 

[1970gsx]

There is a newer product out called Freeze 12. It is suppose to be a direct drop in replacement for R-12. A buddy of mine added a couple cans to his Volvo and he said it blows ice cold. It cost about 9 bucks a can and he bought at a local parts house. Maybe try adding a can or two to your car.

 

[dgreene]

Yep, if it cycles fast then it's low on coolant. 1970GSX is right about the freeze 12. It's a wonderful product and the only thing I use anymore. It's so cheap, and if there's a problem then you won't cry when you have to open the system up. Get a set of gauges and a can or two of freeze 12 and top it back off. I have noticed that on a warm day Freeze 12 likes to have a higher High side preasure than R-12. Somewhere around 220-230 psi is normal but on some vehicles it likes to be run at 240 or so. It's like R-134A you have to find the sweet spot for your AC system.

Good luck.

 

[MeanBuicks]

Freeze 12 is kicking booty in the all-original, untouched 205,000 mile AC system in my GN. Great stuff!

 

[Mark]

Thanks for the replies. I'd guess the compressor is cycling 20-30 times a minute. I was a little surprised by the low-side pressure, and didn't bother to check it with the compressor running.

Is J.C.Whitney the place to get gauges? Anybody do any better at the local parts stores?

 

[Red Regal T]

No reason not to change over to 134A. Just bought some at K-mart for $2.50 a can on sale. Buy a low side adapter and pump in a can or two..............or spend a bunch of money everytime you have a problem.

 

[Danster]

When using Freeze 12, does the exisiting R-12 need to be vacuumed out of the system or can you add Freeze 12 mixed with R-12? Do you have to change any of the o-rings?

My car will be up and running within a week and I know my system is not cooling enough.


Dannyo

 

[dgreene]

You can add freeze 12 to an existing R-12 system with out doing a thing to it. It mixes well. On the other hand I have had problems just vacuuming an R-12 system and putting in R-134A. The oil in the R-12 system is incompatible with 134A and sometimes it couagulates and clogs up the orifice valve. So if you do change over to R-134a be sure to remove the Dryer and orifice valve and flush out the system. Then install a new dryer and a VOV.(Variable Orifice Valve.) That way the R-134a will sure enough be a champ.