Air Conditioning

Well I did really well ..... The damn thing is empty again. Every 'O'ring replaced, evaporator unit checked..... Damn... I assumed it was ok 'cos I found so many issues and the 'vac pump ran silently... Let me guess. Compressor seal that seats under vacuum but not pressure :confused:

seeya,
Shane L.

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Originally Posted by DoubleChevron

Well I did really well ..... The damn thing is empty again. Every 'O'ring replaced, evaporator unit checked..... Damn... I assumed it was ok 'cos I found so many issues and the 'vac pump ran silently... Let me guess. Compressor seal that seats under vacuum but not pressure :confused:

seeya,
Shane L.

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A proper pressure test should have been done before it was filled with refrigerant.

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Originally Posted by scarry

A proper pressure test should have been done before it was filled with refrigerant.

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I do have a bottle of nitrogen here ..... But I use a suicide hose off the bottle from it .... I don't fancy hooking up 160bar (2300psi) to an A/C system :wasntme:

I'll whip the condenser out this weekend hopefully, if it's ok, that only leaves the compressor (I hope not, I don't have the $$$ to replace it at the moment.... It would be worth more than the entire cost!).

seeya
Shane L.

Quote:

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Originally Posted by DoubleChevron

I do have a bottle of nitrogen here ..... But I use a suicide hose off the bottle from it .... I don't fancy hooking up 160bar (2300psi) to an A/C system :wasntme:

I'll whip the condenser out this weekend hopefully, if it's ok, that only leaves the compressor (I hope not, I don't have the $$$ to replace it at the moment.... It would be worth more than the entire cost!).

seeya
Shane L.

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That suicide hose brings back memories:D:(

i would try to pressure test with everything in situ as a joint may be leaking.Just use soapy water.
Maybe borrow a regulater from someone,would be a lot safer.

An Oxy reg used to do the trick until a few years back when they changed the fittings for nitro so it was different from the oxy fitting.

:wallbash: :wallbash: :wallbash: :wallbash: :wallbash:

I reckon this smiley should have my name on it .....

http://www.aulro.com/afvb/attachment...1&d=1455334841

So I fabricated up an attachment so I could hook up my suspension sphere regasser to the A/C system. If the guru's reckon nitrogen is the way to go ........... Well I should give it a crack :)

http://www.aulro.com/afvb/attachment...1&d=1455334841

This is the regassing valve, it's designed to flow small amounts of gas at high pressures ( ~1500psi).

http://www.aulro.com/afvb/attachment...1&d=1455334841

So even though I'm using a suicide line from the (160bar) bottle .... I found I could readily very slowly add nitrogen keeping the pressure below 200psi so I didn't blow the **** out of everything ( :o :blink: )

http://www.aulro.com/afvb/attachment...1&d=1455334841

Anyway, I spent a good 20minutes spraying everything I could think of with soapy water before noticing this ......................... I reckon the reason I can't find any leaks, is 'cos there is none to find. It hasn't even dropped 1psi in the last hour. Which makes the problem obvious....................... And something I ***should*** have noticed without any of this bull**** :(



































http://www.aulro.com/afvb/attachment...1&d=1455334841

Obvious to even a blind man, without even checking. The only thing that has changed is I'm using a service port ........................... So the obvious answer is the service port is the leak. And look at that, no :censored: "O"ring in the cap. :wallbash: :wallbash: :wallbash: :wallbash: :wallbash:

Someday I'm going to learn from my mistakes.

seeya,
Shane L.

Quote:

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Originally Posted by scarry

That suicide hose brings back memories:D:(

i would try to pressure test with everything in situ as a joint may be leaking.Just use soapy water.
Maybe borrow a regulater from someone,would be a lot safer.

An Oxy reg used to do the trick until a few years back when they changed the fittings for nitro so it was different from the oxy fitting.

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Reminds me of when a workmate pressure testing a large rooftop dx chiller grabbed the oxygen cylinder instead of the nitrogen. Pressure tested system to 200psi with oxygen and the crankcase heater on:eek:

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Originally Posted by DoubleChevron

Obvious to even a blind man, without even checking. The only thing that has changed is I'm using a service port ........................... So the obvious answer is the service port is the leak. And look at that, no :censored: "O"ring in the cap. :wallbash: :wallbash: :wallbash: :wallbash: :wallbash:

Someday I'm going to learn from my mistakes.

seeya,
Shane L.

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just to be picky..

you shouldnt need the oring in the screw down cap, while you have the system depressurised remove the schreader completely from within the fitting and inspect that closely. If you have access to gear to do it dont forget to closely inspect the seating surfaces for the schreader, if you're having a sod of a time getting it to seal up theres a good chance that the seat rather than the core seal is damaged.

Quote:

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Originally Posted by Blknight.aus

just to be picky..

you shouldnt need the oring in the screw down cap, while you have the system depressurised remove the schreader completely from within the fitting and inspect that closely. If you have access to gear to do it dont forget to closely inspect the seating surfaces for the schreader, if you're having a sod of a time getting it to seal up theres a good chance that the seat rather than the core seal is damaged.

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Interesting, I only tinker with auto A/C... but I've found the caps almost always "hiss" and release pressure when I unscrew them ......................... Which means the service valves leak .... That is why the service caps have "O"riings in them :)

I just googled it .... sounds like a common issue:

http://hvac-talk.com/vbb/showthread....hat-s-the-seal

seeys,
Shane L.

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Originally Posted by DoubleChevron

Interesting, I only tinker with auto A/C... but I've found the caps almost always "hiss" and release pressure when I unscrew them ......................... Which means the service valves leak .... That is why the service caps have "O"riings in them :)

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This is what I have found also. The O-ring seems to be necessary.

Aaron

Around 95% of the time a new core will fix the problem with a schrader valve.

We find the main issues with schrader cores and orings in the caps are on the discharge side of the system,as the heat seems to destroy them,the rubber or nylon gets hard and brittle.