Power mains question: wire gauge

Hey, the less the content, the longer the thread. This is post #120, and it was decided long ago that the OP can use 12 or 14 gage wire.

They don't make them that that go fast enough to deal with the sewage you produce

You lefties are always projecting your inadequacies.

--- Nicely, that's like the bone between the shoulder and the elbow, which reminds me of an old joke:

During the second world war, the Duchess of Windsor visited many hospitals in order to try to cheer up the wounded and, at one, asked a soldier why he was there.

The soldier answered: "Ma'am, I had to have surgery done on my penis."

"Oh, my, she interjected, did they have to remove the bone?"

"My compliments to the Duke", replied the soldier.

-- JF

done

Well I'm not interested in being quarrelsome but would you mind explaining why you would use copper piping for air lines. Copper has gotten more pricy rather than recently pricey so it would seem to be rather a waste to use it for air. Help me out here. What am I missing?

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In North American Practice the electrical codes forbid assembling conduit around wire. The conduit must be built as a complete assembly and then you pull the wire from pull point to pull point.

A reasonable alternative.

I've seen the pipe fitters install hundreds of feet of black iron on jobs with a lot of air in use such as assembly lines. What is wrong with that? Is it too expensive to install to be cost effective? I have been out of the big job work for over a decade now.

Black iron is incredibly expensive and impossible to work with.

I bet people are using Pex to carry air these days. Pex is displacing copper pipe for residential water service as well. The plumber installing Pex for part of my circulating hot water heating system commented that if one bids straight copper, one does not win the job.

Joe Gwinn

I thought about using PEX, though wasn't sure if it could take the pressure. A faulty regulator can easily dump 120-200lbs into the system. At least it wouldn't shatter like PVC, though. It's an idea, though I think I already have about half the copper I need for the job. ..though that probably means I'm short 3/4. ;-)

My other house has PEX for its water supply. I have no idea if the house is "normal" but I don't like the stuff. Only one of the outside faucets has any volume and the inside faucets are all weak. It seems there is a lot more pressure/volume lost in the distribution than there is in either the copper systems I've had in the past or the PVC in the new place. One big advantage of PEX for water is temperature stability (someone flushing a john doesn't scald the person taking a shower). Another is the manifold allows one to turn off individual appliances. It's handy for turning off the silcocks in the Winter, though I added ball valves to the distribution system (copper) in my VT house to accomplish pretty much the same thing.

Here is some PEX data:

At 74 F, the rating is 160 psi. The installation proof test is 1.5 times that, or 240 psi. That ought to work.

As for broken regulators, if it's a real problem, I would add a simple overpressure relief valve to handle regulator blowout, protecting more than just the tubing.

Sounds like the installer cheaped out and used too small a diameter of tubing/pipe. This never happens with copper pipe. Never....

Joe Gwinn

Depending on the result, it might be something to worry about. With copper, not so much. PEX probably not, either, but it's failure mode would be important. PVC, absolutely!

I've never seen anything less than 3/4" and 1/2" in homes. Sure, I've seen problems with temperature regulation when they cheaped out but never a supply problem. Even 1/2" was plenty for a hose bib or a kitchen sink. ISTM, that PEX has a *lot* more resistance than copper.

The Romans used lead to carry their water and as a result some developed lead poisoning. Plastic is the new lead.

Rick

Utter nonsense. I'd expect as much, though.

No, idiot. They used a lead acetate compound to sweeten their wine.

The inside of PEX is just as smooth as the inside of copper pipe, and there are usually fewer ells needed with PEX (or copper tubing for that matter). Something else is the matter.

Joe Gwinn