Galvanic Corrosion issue??

Users who are viewing this thread

Merr203

Member
Messages
34
Reaction score
4
Points
8
Location
WA
I did search around but didn't find anything that made me feel better, only made me more concerned. I need to extend a pair of supply hoses using a galvanized steel nipple. I'm pretty sure the hose nuts are nickel coated brass. This will be hot & cold supply for a washer. Is this combo OK or do I need to find some brass nipples?

uiegmZH.jpg
 

hj

Master Plumber
Messages
33,602
Reaction score
1,041
Points
113
Location
Cave Creek, Arizona
Website
www.terrylove.com
galvanized in water WILL rust and it has nothing to do with electrolytic action. I am not sure how you are extending the hoses, but in most cases you would want a brass MHTxMHT coupling between two washing machine hoses.
 

Merr203

Member
Messages
34
Reaction score
4
Points
8
Location
WA
In the pic above I'd be extending by connecting two hoses to the nipple. Sounds like I may want to just get the brass. The nipple was sold in a plumbing supply store (not a big box) for this purpose, I just wanted to double check.
 

Terry

The Plumbing Wizard
Staff member
Messages
29,942
Reaction score
3,459
Points
113
Location
Bothell, Washington
Website
terrylove.com
Most washer hoses use hose threading, not NPT.
The connector you show is FIP or standard 1/2" pipe thread. I use brass nipples for that.
 

Merr203

Member
Messages
34
Reaction score
4
Points
8
Location
WA
This is going before the washer supply. Between the Spigot and CPVC piping. I'm replacing these ancient supply hoses. 30" is too short and I can't find 36" FIP to FIP. I don't see another way to do this as the space is too tight for pex.

VUxgRGX.jpg
 

CountryBumkin

Active Member
Messages
915
Reaction score
70
Points
28
Location
Orlando, FL
I can't tell from your picture, but do the flexible lines in the wall go to "shut off valves"?
I would cut out the flexible lines in the wall and run CPVC up to a shutoff valve group, then use the flexible hose from the shutoff to the washer. Then close up the opening. Something like this: https://www.ebarnett.com/Sku/531200

531200_usn.jpg
 

Terry

The Plumbing Wizard
Staff member
Messages
29,942
Reaction score
3,459
Points
113
Location
Bothell, Washington
Website
terrylove.com
I don't care for the vinyl braided hoses there. I would use PEX to the washer box.
It looks like SharkBites on 1/2" CPVC there.
That would work for PEX too.

While you are at it, maybe change out the p-trap to 2".
What you have is undersized 1.5"
 
Last edited:

Merr203

Member
Messages
34
Reaction score
4
Points
8
Location
WA
Just curious; why are you replacing them?

These things are known to fail & they may be upwards of 20 years old. Since I'm installing a laundry sink and I have the access panel open, I figured I should do this as well. Because of the tight space I'm just going to use splitters on the laundry box to supply sink and washer.
 

Merr203

Member
Messages
34
Reaction score
4
Points
8
Location
WA
I don't care for the vinyl braided hoses there. I would use PEX to the washer box.
It looks like SharkBites on 1/2" copper there.
That would work for PEX too.

Yes there is a washer box up there (and it leaks). I have a new one with MPT connections as part of this project.

It's hard to see but the trap is almost directly over the CPVC. I don't think more CPVC or pex will work due to excessive bending. I thought about going behind the trap but even that may cause too much stress. Note also the hot and cold are skewed towards each other. So if I extend them it will cause stress at the point where they come through the floor. I could try and widen that space in the floor but am afraid of damaging the pipe -- then I will end up in the crawlspace pulling out insulation.

If I could find a 1/2" x 36" steel braided flex line, it would be great. But instead I ended up with 12" + 24". As mentioned at the top of the thread, the galvanized may not corrode but will eventually rust. So I went ahead and ordered a pair of brass MPT nipples. This isn't ideal I know but it seems like the best way short of tearing up the wall and re-plumbing everything.

I'm mainly trying to get this project done so my wife will have a sink to use while I go about updating the kitchen sink/faucet/disposal & countertops. So I'm trying to avoid scope creep as much as possible... ;)
 

Kreemoweet

In the Trades
Messages
754
Reaction score
66
Points
28
Location
Seattle. WA
Flexible water supplies are only allowed to be used in exposed locations. Moreover, they can not be used as part
of the permanent water supply piping, exposed or not, as OP seems to be doing.
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks