Home>Discussions>PLUMBING>Water Heater Outlet Pipe Exterior Corrosion
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Clinstructor
Water Heater Outlet Pipe Exterior Corrosion

My water heater is not leaking water. However, the hot water outlet pipe, where it is connected to the extension pipe, has a green and rust colored flaky corrosion building up on the outside. I suspect that this is related to the hardness of the water within our public water supply. The water heater is guaranteed until 2014 with a double anode rod setup. Should I be concerned about the corrosive flakes? If so, what would you recommend that I do? Many thanks!

dj1
Re: Water Heater Outlet Pipe Exterior Corrosion

What type of pipe is it? brass, copper, galv. etc?
knowing that will make it easier to suggest a remedy.

Clinstructor
Re: Water Heater Outlet Pipe Exterior Corrosion

Although I do not know the composition of the pipe leading directly from the water heater, the extension pipe is definitely copper. Thanks!

HoustonRemodeler
Re: Water Heater Outlet Pipe Exterior Corrosion

Green is an indication of copper pipes. Verdigris is the name of the "rust".

Verdigris is fairly normal but there shouldn't be much if any. It sounds like you've got a pinhole leak and that is making more verdigris.

My advice; Take it apart, clean or replace the copper bits, use Teflon pipe dope to re-assemble, tighten securely without muscling it to death. Or use those stainless steel HWH connector pipes.

Clinstructor
Re: Water Heater Outlet Pipe Exterior Corrosion

Many thanks!

lightningbug
Re: Water Heater Outlet Pipe Exterior Corrosion

I've got pretty much the same thing going on at my house as the original poster, but this seems to have just set on in the past 1 mo and the heater is approx 7 yrs old. Would there also be an anode rod issue (as I have a Bradford-White) with a combo anode/outlet? Gavanized pipe (from wh) to copper.

dj1
Re: Water Heater Outlet Pipe Exterior Corrosion

Quote: " Gavanized pipe (from wh) to copper. "

If your galvanized pipe is in direct contact with copper, you will have future problems.

lightningbug
Re: Water Heater Outlet Pipe Exterior Corrosion

I am probably wrong that it is galvanized - but it is definitely not copper or brass (referring to the hot water outlet).

Mastercarpentry
Re: Water Heater Outlet Pipe Exterior Corrosion

A magnet will not be attracted to anything but steel and more weakly to iron (not used as supply piping), so if a magnet sticks, it's galvanized- guaranteed.

Phil

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