I'm looking at some hot water pipes in FloriDUH that might have been 1/2 or 3/8 when they were new but that wonderful water has then choked down to maybe 1/4 after 20 years.

Yes, the right thing to do would be to tear open walls and ceilings (the pipes run the ceilings) and run new ones. That ain't gonna happen, too much fuss, too much repainting , too much for the elderly residents.

But I've been wondering about an alternative some folks have raised, of draining the hot water tank, plugging the lines where they would enter it, and then pumping CLR or LimeAway or even muriatic acid back into the hot water lines, all the way from the tank to the showerheads and faucets. And then flush and repeat.

The stuff DOES break down mineral deposits, so it sounds like it might work. Has anyone actually had experience, success, or disaster doing this? Or found another way to rejuvenate old pipes?

In the worst case, we couldn't even snake in new PEX and abandon the old ones, too many holes too much painting and plastering would have to be done.

You're right, the ever-helpful Alibaba.com instantly offered a hundred "most best quality casting house" sources in China who would make up that 40-inch-to-one-half-inch (specify OD or ID and thread or flange) casting adapter for me. Brass, bronze, stainless, whatever you want, you can find on the internet.

I'm more inclined to just disconnect the outlet from the hot water heater and start pouring a gallon of CLR into each shower head until something green runs out the back end, then stick a cork in it and let it soak for a few hours. If the pipe actually FAILS....that's covered under a service agreement.

I'm more inclined to just disconnect the outlet from the hot water heater and start pouring a gallon of CLR into each shower head until something green runs out the back end, then stick a cork in it and let it soak for a few hours.

That sounds good to me. I might do it in the other direction.  But for a different problem.

I chlorinated my system a year ago, according to the well drillers instructions. Poured two bottles of bleach down the well and let the garden hose run back into the well for an hour. That ensured mixing and the entire house system was chlorinated. The water tasted of chlorine for a week, but it supposedly killed all the iron-loving bacteria that had been making the water stink. But now, the hot water stinks again. I have been trying to figure a way to disinfect just the hot water part of the system. I guess I could disconnect or shut off the tank from the system. Attach a garden hose to the tank drain and start it draining. Pour bleach into a shower head upstairs. Or into the cold water quick-connect to the tank. 

What do you think?

Cal, from West Michigan

All generalizations are false, including this one..

I'd heard of anaerobic bacteria living on a sulfur cycle making water stink, never heard of iron-loving critters doing it. And would assume they'd come up form the ground with the well water, so killing them wouldn't accomplish much unless you back-pressurized the earth beneath your property.

That is possible. But I am hoping that they are in the pipes. The cold water does not stink.

FWIW we had a new 90 ft well put in a couple of years ago because the old well pipe was leaking and rusty. Hopefully that was the only source of iron. I assumed the stink then was from infiltrating surface or shallow water.

Now I add iron remover to the water softener and I hope that will keep any new bacteria from growing. Chlorinating the hot water tank will be a temporary experiment. I will keep your UV idea in mind.

Cal, from West Michigan

All generalizations are false, including this one..