Galvanized pipe?

swyman · Post by **swyman** » Sat. Dec. 16, 2017 6:42 pm

Help me out but didn't I read somewhere that you are not supposed to use galvanized pipe on these boiler systems? I used all black pipe but needed a 1 1/2" x 1/2" bushing to install a couple temp gauges. The store only had 1 black and 1 galvanized....I bought both but want to make sure I'm not making a mistake with the galvanized?

Post by **Rob R.** » Sat. Dec. 16, 2017 6:53 pm

It will be fine.

windyhill4.2 · Post by **windyhill4.2** » Sat. Dec. 16, 2017 6:55 pm

Why is it that i have always heard that 1 should never use galvanized for hot water pipes ???

Post by **Rob R.** » Sat. Dec. 16, 2017 7:07 pm

If used for hot domestic water, galvanized ends up plugging with mineral deposits and rust. Considering that there is no (or hardly any) oxygen in a pressurized hot water heating system, you don't need to worry about the pipes plugging. One thing I have heard is that glycol and galvanized don't play nice together - if there is any plan to put glycol in the system it might be best to stick to black iron or copper. I don't think one reducing bushing would matter anyway, but better safe than sorry.

The original monoflow heating system in my house from the 1950's has galvanized piping for the mains.

windyhill4.2 · Post by **windyhill4.2** » Sat. Dec. 16, 2017 7:11 pm

Rob, thanks for that info,i have often cringed when looking at some pics of installs with galvanized pipe. I had been told when i plumbed my OWB in 2006 that i should not use galvanized.... but that unit was an open to the air tea kettle.
Now hopefully i can remember the difference from here on.

Post by **coaledsweat** » Sat. Dec. 16, 2017 7:20 pm

Dont use it unless you can't avoid it. Fine for an emergency fix but it is problematic. And it looks funny.

hotblast1357 · Post by **hotblast1357** » Sat. Dec. 16, 2017 7:29 pm

Paint it black no one will ever know..

What did you decide to do with the pex install?

swyman · Post by **swyman** » Sun. Dec. 17, 2017 7:53 am

Thank you for the replies... I just wanted to make sure before I installed it. Easier now then to have to change it after I get the system filled. In it goes!

freetown fred · Post by **freetown fred** » Sun. Dec. 17, 2017 7:59 am

Don't forget some progress pix S.

Hambden Bob · Post by **Hambden Bob** » Sun. Dec. 17, 2017 10:18 am

coaledsweat wrote: ↑
Sat. Dec. 16, 2017 7:20 pm
Dont use it unless you can't avoid it. Fine for an emergency fix but it is problematic. And it looks funny.

Hell,I look funny,and I'm not Galvanized,but I am Expendable,here,in The Coal Zone ! On a serious note,for the long haul,go as High Quality as you can afford,and keep the Oxygen out.....

lincolnmania · Post by **lincolnmania** » Tue. Sep. 29, 2020 11:05 pm

found some galvanized 1.25" unions for 4 bucks a piece. black ones are 10 dollars each.
yay or nay?

lzaharis · Post by **lzaharis** » Wed. Sep. 30, 2020 9:10 am

NO!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! USE BLACK IRON.

Post by **Rob R.** » Wed. Sep. 30, 2020 12:11 pm

lincolnmania wrote: ↑
Tue. Sep. 29, 2020 11:05 pm
found some galvanized 1.25" unions for 4 bucks a piece. black ones are 10 dollars each.
yay or nay?

Although I don't think the galvanized would hurt anything, I suggest you by some Ward unions (USA made) and save yourself the headache of dealing with a leaker.

Holdencoal · Post by **Holdencoal** » Wed. Sep. 30, 2020 1:16 pm

galvanized steel is not recommended for use with glycol heat transfer fluids. The galvanized steel coating was applied to protect against atmospheric corrosion. If used with heating, as the fuild temperature goes above 120 deg F the steel will rust away first, protecting the galvanized coating / lining.