Another possibility is low refrig. and air in system, when compressor cycles does the low side gauge rise and fall or is it stationary ? When compressor is real weak or on its way out is the low side gauge can sometimes not move.
Puzzling reading on AC gages.
- Thread starter Snagglefoot
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Another possibility is low refrig. and air in system, when compressor cycles does the low side gauge rise and fall or is it stationary ? When compressor is real weak or on its way out is the low side gauge can sometimes not move.
some cars also have variable flow compressors, so the compressor might not be running at max if it's not hot enough. and these variable flow compressors have a solenoid that can fail and give weak a/c compressor symptoms. this is on Volkswagen cars though, yours is probably different. also if it's cool outside the a/c will have lower pressure than when it's hot outside.
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I think the joint is sealed by an o-ring, and the torque of the bolt just keeps everything together. Probably need to replace the o-ring to fix the leak.
By the way, I have just over 40 psi on the system in the static mode. I have a call into Duracool in Toronto to find out what the pressure should be knowing that a propane/isobutane mixure would produce its own pressure in a sealed system. Stay tuned and thanks for the tips.
I received some help from Duracool. Generally the static pressure is usually about numerically the same as temperature in degree F. In a properly charged system while the compressor is running, the low pressure side will be about 35 psi and the high pressure side will be about the ambient temperature in F plus 100 F. I’ll add a bit more refrigerant.
If you know that your vehicle has a variable displacement compressor:
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Diagnosing Variable Displacement Compressors | MOTOR
In earlier air conditioning systems, the compressor ran at full capacity whenever its cycling clutch was engaged. If the engine was running and the clutch was engaged, the compressor was pumping. And the faster the engine turned, the more pressure the compressor developed. The only way to...
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I left the charge at a static 43 psi. The daytime afternoon temp coming back from work is 82 F. The temp coming out of the vent is 62 F and the automatic air conditioning is set for 68 F. Its actually quite comfortable. I think I'll leave it for the week and see if I lose any more charge. (Keep in mind its HC, not 134A.)
If it can keep its charge I may bring up the static charge to 70 psia and see how it works. Fun experiment. Meanwhile I'm checking costs on a new compressor. Thanks for reading.
If it can keep its charge I may bring up the static charge to 70 psia and see how it works. Fun experiment. Meanwhile I'm checking costs on a new compressor. Thanks for reading.
Vent temperature chart, seems like your vent temp at 62F is alittle warm!
| Ambient temp | Low side pressure | High side pressure | Center vent temp |
60°F | 28–38 psi | 130–190 psi | 44–46°F |
| 70°F | 30–40 psi | 190–220 psi | 44–48°F |
| 80°F | 30–40 psi | 190–220 psi | 43–48°F |
| 90°F | 35–40 psi | 190–225 psi | 44–50°F |
| 100°F | 40–50 psi | 200–250 psi | 52–60°F |
| 110°F | 50–60 psi | 250–300 psi | 68–74°F |
| 120°F | 55–65 psi | 320–350 psi | 70–75° |
| of refrigerant pressures vs. ambient (outside) temperature |
Today I connected the blue hose ( low pressure side) and took a static pressure. It was 55 psi at an ambient temp of 72 F , giving me some confidence the system is still holding refrigerant. I plan to add in a partial can and get to try get the static pressure to 70 psi. I fully realize the better way is to drain and put the system on vacuum and start again, but I might be replacing the compressor anyway so thought I’d see what the system is capable of with a bit more charge. Now to pick up a can or two of Duracool HC refrigerant.
His vent temperature is warm, but so are those on the chart. Those are minimums your ac system should hit.
Thanks for the interest, but one drop of refrigerant would be 70 psi? That’s typically not what I see. I’ll do an experiment and load one more can and check the static pressure again, then I’ll do a full run test with both gages.
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If you want it to work like factory fix the leak and charge it back up with the proper weight of R134a.
I'm not an ac guy, but I think filling to operating pressures is a better approach than static pressure.
Do you have dye in the system?
You can borrow a dye injector from AutoZone, as well as the UV light.
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I'm chasing a leak on mine as well. You're in the exact same boat as I am.
System holds 34oz. refrigerant, in my case.
System holds 34oz. refrigerant, in my case.
In some compressors, the compressor clutch gap can actually be check and adjusted for better performance.
The increase in gap mimics a weak compressor.
The increase in gap mimics a weak compressor.
+1, and change out the receiver/drier while you're at it.
Thanks, yes I agree with that. I did the quick static check and will load in more refrigerant and do another proper two gage test. There is dye in the system and I have a black light.
