Purge and Deep Vacuum?

beenthere

What kind of a leak test? What do you want them to show you.

Just did a 2 ton system that took 2.5 hours to pull below 500 microns.

Klawman

I jusst thought they did a seperate leak test. They ran a vacuum for two hours and told me that it pulled 500 microns. Anyway, they finished and it works pretty well, wxcept it seems to only work on a single blower speed and is a 2 speed. Given that they aren't even billing me until some tiles are replaced I think it will get fixed without delay.

Master of Cold

Relax dude...if it leaks, someone will come back and fix it. The two speed blower, hi for cooling, low for heat. If the tech is going to spend the money on digital gauges, I wouldn't worry too much about it. You have to care about your work to spend that much money on a manifold set.

Doc Holliday

I don't.

Doc Holliday

And we don't weld, we braze.

Doc Holliday

It shouldn't leak to begin with. If it does, I'd be a concerned home ower.

JJboy

heheheheh yes braze

__________________

**Always kill the power ** Hot air rises, but heat will always move from higher to lower temperatures. ** Real man shoot in manual. ** If it ain't grounded, it ain't dead.

Klawman

That is what I was thinking. I don't think it is leaking and they probably did a good job, but to be safe I may not use their referral to do a HERS.

I don't understand the point, but the guy left his gauges hooked up after he pulled a vacuum and they read between 245 and 258 PSI for about an hour. The reading fluctuated with the temperature.

I almost thought it humerous when the sales guy showed up at the very tail end of the job to show me a permit application that he couldn't get a permit issued on, because the city wouldn't take a credit card.

Doc Holliday

JJboy, reason for not FLOWING ntirogen while brazing is once the lineset is brazed, remove the shraeder cores from the service ports. Actually, remove them before you braze to not burn the rubber seals. Hook up nitrogen via gauges and put 2 to 3 psig and let sit for a few minutes. Do not dumb via gauges, dump via disconnecting hoses from service port. Then re-attach hoses to ports and fill up with nitrogen to 200 psig for pressure/leak test and let sit for ten minutes. Once it is confirmed that no leak is present, disconnect hoses at ports and any applicable trash be it oxidation flakes or existing will blow out through the shraeder ports.

Done deal. The lineset has been pressure tested and cleaned as a two fer with one stone.

Re-install shraeder cores and then vacuum.

Believe you me, it works.

JJboy

I already do the first part ..... I will try the second part next time. I'm using this.

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__________________

**Always kill the power ** Hot air rises, but heat will always move from higher to lower temperatures. ** Real man shoot in manual. ** If it ain't grounded, it ain't dead.

beenthere

If your flowing nitrogen while brazing, there will be NO oxidation.

jerryk1234

*** Wow, that's cool. I WANT one. They're a bit pricey though. Bet I could make one up on the lathe. Only interested in 3/4 and 3/8. But how much is my time worth? Wouldn't take much to add up to $40....

- JerryK

Doc Holliday

There will always be oxidation as the last braze one can not flow nitrogen through as the opening is now gone as that last connection was where nitrogen was flowing from. Am I right or am I right?


Gotta go, I have a Goodman 4 ton condenser to install this morning that I will not be flowing nitrogen while brazing but I will be taking pics of the procedure I previously explained.

Marty S.

Pull both schrader cores Doc then have a trickle of nitro flowing. I'll give a good blast to fill the lines then pull the hose off and dial the regulator down until it can barely be heard coming out of the hose. Hook back up and braze, no oxidation that way.

Doc Holliday

Yeah, as soon as I posted I realized it could be flowed that way. Oops.

If we get an authorization on this dang condenser I'm waiting on I might give it a try today.

Thanks.