Cap Tube Testing?

[coldcanadian]

Hey all,
It's been almost 4 months since I've been on the forum. I went back to school, but didn't learn much, lol. Anyway, I'm back at the summer job for a few weeks over the Xmas break and I have a new question for anyone who's listening.

Since the summer, the manufacturer I work for has finally brought in pre-cut cap tube, an accurate fill station and some other minor things. Now they would like to set up a station to check the cap tube and evaporator for leaks and flow restrictions. Anyone ever seen what other manufacturers do to check this? I'm sure I could us a super accurate flow meter, but they are pretty expensive. Apparently we had some big wigs in and they said they used pressure? Any ideas?

I've been experimenting with building a known pressure, say 100 PSIG, and then venting it thru the cap tube to get a pressure difference, approximately a 1.10 PSIG drop. It seems to be repeatable, but differing the length of the tube does not affect the outcome as much as I thought it would. Also, I might have a wacky regulator because everytime I adjust it, it sets my new repeatable measurements to a new level. EX. If I set it to 100 PSIG again, the new drop will be 1.05 and be repeatable. Even if I set the regulator back to the exact same pressure, the pressure drop changes but is still repeatable at the new pressure drop.

Anyway, thought I'd at least let you guys know I'm still alive. Next semester I finally get to take an HVAC and refrigeration course so I'll probably have many questions, lmao.

Hopefully someone out there has seen a cap tube tester in action and can let me know how it was set up.

Thanks in advance,

Ken

[coolclassics]

Fellow Canadian eh.

Philco corp made several different types of metering device testers throughout the 50's and right up until mid 80's.

these suitcase looking tools were amazingly accurate and built to last.

I have seen them listed on ebay for $20 - $50.


have a great new year

[R12rules]

contact Supco. Sealed Units Parts Co. If they dont have advice for you, start calling numbers in the News Directory.
If you dont have that directory, order it overnight cause you need it.
It may even be available online now.


Helium is best for leak testing. But for flow rate measurements .... I dont know.


Oh ..... try Omega Engineering. They would know something.

These guys are so friendly and helpful .... you'd swear they were Canadians or something!!!