[bhill86]

I don’t suppose there are any A/C experts out there that can assist me in my recharge efforts.

I tend to be long winded in these so I’ll try to be short without skipping useful info.

77 T/A, factory air car with the original evaporator in place. Everything else from there forward was gone.

First, flushed evaporator core with an entire gallon of A/C flushing agent until it was clean. Only old oil came out. No debris.

Next, purchased a stage 2 kit from Original Air which included all new lines/hoses, compressor, condenser and accumulator.

I installed that over the weekend, evacuated the system, held vacuum to ensure no leaks (though I did end up with a leak at one point under pressure that I fixed), evacuated for 45 minutes then proceeded to charge.

Had both manifold valves closed, hooked up my first 12oz can of R134a, purged the line, car running, A/C on, opened the valve on the low side slowly and it pulled in some refrigerant but not much. Probably only about 3oz or so. I wasn’t measuring because I needed at least 3 cans (36 oz) plus some from a 4th can which I planned to measure.

The ambient temp was around 90° and it seems like the system wouldn’t suck any more refrigerant. The low side reached high enough to engage the low pressure switch (LPS) and compressor and the high side climbed no higher than 150psi. Once it reached that area the low side will have dropped below the LPS threshold and the compressor will shut off and the pressures will begin to equalize until low side engages the LPS again. Lather, rinse and repeat. It doesn’t draw any more in from the can on the low side and high side pressures never reach what I’m reading they should on a hot 90° day (250-270 psi)

This is my first time messing with A/C but I feel like either the compressor is weak, the orifice tube isn’t creating enough of a restriction (if that’s even possible) or I have a leak but that doesn’t seem feasible either. Any thoughts?

[bhill86]

I don’t see the option to edit fir some reason so I’ll add here, the reason I question whether or not it’s a leak is #1, it doesn’t seem to lose refrigerant while at rest though it’s hard to tell 100% due to the pressure changes that occur with ambient air temp changes. #2, I would think it is unlikely for a leak to act as a pressure release valve so to speak. I mean I would think it was unlikely the system (somewhere on the high side) would only leak at pressures around 150psi but not at pressure lower than that.

Lastly, I would think if there was somehow a leak, when the high side pressurizes as the compressor kicks on, it could force refrigerant out, thereby causing the low side to drop far enough to allow more refrigerant in from the can. I would think it would essentially, eventually, drain the can by pulling refrigerant out of the can, into the low side, compressing into the high side where it’s escaping under high pressure. Correct me if I’m wrong of course but I don’t THINK that’s what’s happening.

[Cardo]

I pretty much fill mine the same way as you do, and have had that same problem. sit the can in hot water and that will force it into the system. It's always worked for me without a problem.

[bhill86]

Interesting. So without the hot water you’ve had trouble with the system not pulling refrigerant into the low side?

[bhill86]

Well, I tried it with warm water and was able to get it to take refrigerant. I didn’t have a lot of time to test but at idle I had vent temps around 49° and while driving around it dropped to 43°. It’s around 80-82° degrees today so I don’t think that’s terrible but there may be room for improvement.

Thanks for your suggestion.