static a/c pressure question
 

Im chasing down a small leak that developed while changing out my evap core. It wont hold vacuum for more than a few hours.

I have put a small charge of freon, and pressurized the rest with nitrogen. I am aware that static pressure is about 80 psi, but was wondering if I could pressure test at 150? 200? Whats the max?

You can pressure check with as much pres you can get from your nitrogen bottle. Do you have a sniffer?

The nitrogen bottle is over 1,000 psi. I went with 100 so that I could get a read on both gauges. I'll report back in a few hours to see if it holds or not.

The sniffer I bought from fleabay. It does not really work as well as I hoped. Any good leads on a decent sniffer? Maybe one with a fan?

Article here discusses using nitrogen @ 200 psi with an small R-22 charge.

Trouble finding A/C leaks? (especially with 134a)

I've seen R-22 mentioned on the forum here also, as an aid to locating leaks, not as a refrigerant.

Is the 1,000 PSI the maximum scale on the gauge?

I was under the impression that at room temperature, nitrogen was at about 250PSI. Whatever it is, you can pressurize the a/c system with 200PSI after putting in 2oz. of R22 and your sniffer will detect leaks really well, even on the low side.

Hope this helps.

If you do find any leakage around O ring joints or at the sensor terminals likely a worn compressor seal .
Now the best way to check for seal leakage?

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What seal are you asking about, the shaft seal?