On Tue, 09 Jun 2009 23:09:52 -0500, Richard J Kinch
wrote:

Corroded brazed joint to an R-22 heat pump:

http://67.207.131.7/poolheater.jpg

Doesn't look to me like this has enough sound material left to be spliced
back together with a new braze.

Is there any good way to put a new fitting into the side of these
hermetically sealed compressor cans?

I just had another thought that requires a seperate post - Looks like
you lost some oil when it rusted through. You don't want to waste
several hours getting that system all fixed up, only to have the
compressor sieze on you.

Cut loose both the suction and discharge, and one of the blanked off
process tubes on the side of the can will let you dump the oil out of
the compressor crankcase when you pop it open.

Find a Cut Sheet for the compressor online, they will tell you how
much oil it takes and show an internal diagram and what each tube is
used for. Sometimes they are just alternate suction inlets depending
on system layout - and you might be able to switch over to it...

Some low temperature refrigeration compressors have a loop of tubing
in the crankcase for an oil cooler, and all you'll get is to the other
end of the tube.

Drain the old oil - measure for reference. And if the amount that
comes out is way short, you just saved yourself...

Braze an access valve on that process tube for future use, and braze
the compressor back into the system.

Then get a refrigeration oil hand pump (looks like a miniature
bicycle pump with 1/4" Flare fittings) and a bottle of the right type
(Mineral, PAG, POE depending on the refrigerant) and weight
refrigeration oil, and put in a fresh oil charge.

You can find the oil in quarts so you don't have to get a gallon AKA
Lifetime Supply. The pumps are usually calibrated at so many ounces
per stroke - RTFM. (Yellow Jacket 77930 is 3.8 oz., 77940 is 2.6 oz.)

There might be some old oil still running around in the lines and
coils, but that's okay. A little too much oil in the system is a
whole lot better than not enough.

A lot too much is bad, but you would really have to work at
overfilling it that much.

-- Bruce --