Have old galvanized 1/2" domestic hot water pipes/fittings w/ low flow. Rinse with vinegar??

sbachman7117

Any suggestions on how/whether to try dissolving the calcium inside my galvanized hot water supply pipes? I know it would be best to replace them with PEX, but that would be really disruptive in this old 4-unit apartment building.
I'm considering siphoning vinegar into the pipes, letting it soak and then flushing it out. My fear is that the calcium might be actually sealing the threaded fitting joints at this point, and that I might end up with leaks inside the walls after the vinegar dissolves the calcium.
Anyone have experience with this?
Thanks!

Jamie Hall

If it's galvanized, the flow restriction may be rust carbuncles, not carbonate. See the thread on piping. If so, vinegar won't help a bit -- and may make it much worse, as well as opening leaks you never knew you had...

ChrisJ

sbachman7117 said:

Any suggestions on how/whether to try dissolving the calcium inside my galvanized hot water supply pipes? I know it would be best to replace them with PEX, but that would be really disruptive in this old 4-unit apartment building.
I'm considering siphoning vinegar into the pipes, letting it soak and then flushing it out. My fear is that the calcium might be actually sealing the threaded fitting joints at this point, and that I might end up with leaks inside the walls after the vinegar dissolves the calcium.
Anyone have experience with this?
Thanks!

Well.
I had a very very old galvanized water service line and the solution I came up with was a shovel, pick axe and a sawzall.

Mad Dog_2

Let sleeping dogs 🐕 lie.   Until u can afford to repipe, don't even LOOK at it cross-eyed.  Mad Dog 

sbachman7117

Thanks guys! I guess I'll just keep ignoring it. I'm pretty good at that.

Larry Weingarten

Hi @sbachman7117 , A question... What is the complaint? Is it slow flow, low apparent water pressure, or ??? If it's low pressure, low flow aerators and/or showerheads could help.

Yours, Larry

Jamie Hall

@Larry Weingarten has an excellent point -- if there are aerators on the faucets, or a flow restrictor in a shower, I'll bet they are clogged with rust particles. Try that first. It's easy!

sbachman7117

Unfortunately, it's not the aerator or even a deteriorated shutoff valve washer clogging the flex line to the faucet. I disconnected the flex line and the flow is low at the shutoff valve. Probably a galvanized elbow full of rust.
Thanks again for the suggestions and wisdom!

Larry Weingarten

Hi @sbachman7117 , I've dealt with that problem. The brass shutoff causes the steel nipple to rust and block flow. The best fix I've found is to remove the valve and replace the nipple with a plastic lined steel nipple... then replace the valve. Here's a source: https://www.matco-norca.com/product.cfm/Nipples/Dielectric-Nipples/product_id/38 And here's another: https://www.ebay.com/itm/152217222136?hash=item2370da7bf8:g:wsYAAOSw6n5Xvbsb&amdata=enc:AQAIAAAA0I0cvLmeo0ChBgQJaF1lW9UHUA4pbNArjyPu8lf6uu5NmivPGR3MsrnbQihbwJYuZcW7jIRoOUXV/UN1bzeWIV5mdvK91TAjWLO+MXgTKeKq8l76J04dwlVpVXl1g99Lv6fV5d/AwKIxNA4djT+g+22nxHYMjbCXPeGstiaGq83AWnNvpgPfUL2iq9nQAgDjiu4hjAgxG0VDgzxgbP1C5n+5OOBERsOfkFLlld9WVrLvnvaf7malI8FTQYCsZufrKtQ4ouwe4GK21MBNEjDTVoI=|tkp:Bk9SR5SL0Mz0YQ
Second best is to clean out the rust, but you know at some point the junction will leak.

Yours, Larry