Parent's Water Heater Valve Leak Causing Rust

[lordmoosh]

Hello all,

My parent's have an old water shut off valve above the water heater which has been leaking for a while and causing the top of the water heater to rust. I can see the droplets come out from where the shutoff valve is inserted into a brass T. Not sure if these two pieces are actually all one piece or two seperate pieces. I am going to replace this valve with a ball valve. The water heater is about 7 years old and is made by GE. It looks good everywhere else except the top. I flushed it last year and did not notice any build up come out of it. I have attached pictures. I have a few questions:

1) Right now the shutoff valve is above the cold water inlet. Should I add a shut off valve over the hot water outlet?

2) The copper is connected directly to what appears to be galvanized steel (or some other type of rusted) nipples in the water heater. Shouldn't there be brass fittings between these two dissimilar metals? Should I do anything about that at this point?

3) What should I do about all the rust, sand it off?

Thanks all.

[Gary Swart]

Rust only comes for iron or steel. That nipple is the culprit. No need to put a valve on the hot water side, when the cold (intake) valve is turned off, no water goes out so a valve is not needed.

[lordmoosh]

Rust only comes for iron or steel. That nipple is the culprit. No need to put a valve on the hot water side, when the cold (intake) valve is turned off, no water goes out so a valve is not needed.

Does there need to be a dielectric union between the nipple and the copper? What should I do about the rusted nipple and rust on top of the tank at this point?

[Gary Swart]

Here's what I'd do, but it may not be code in your state. I'd make the connection of both the cold and hot lines with flex copper. This is a much simpler way to connect than the hard plumbing that you have. But, some states allow this and some don't. I'd replace that rusted nipple with a dielectric one, no need for a union if you go with flex pipe. If you have to stay hard plumbed, I'd use the dielectric nipple, adapter to copper, and a regular copper union. A wire brush would help clean off the rust from the tank. Note: If you use a flex pipe, these must be replace anytime you disconnect them. They have a gasket in the connection that is not supposed to be replaced or reused. If you don't disconnect them, then they will last indefinitely.

[hj]

Those nipples WERE dielectric ones, but the cold water nipple has to be replaced with a new one or a brass nipple.

[lordmoosh]

Those nipples WERE dielectric ones, but the cold water nipple has to be replaced with a new one or a brass nipple.

Why do water heaters get installed with non brass nipples to begin with? Would this be a good replacement choice?

http://www.homedepot.com/p/t/1001334...0#.UT9R6hzCaSo

Can I connect copper directly to this? Should I use nylon tape on both threads of the nipple or do you guys use pipe dope?

[joemcl]

Exact replacement. You have to solder the female adaptor on copper first. Do not solder adaptor on nipple. I use tape and dope.

[Gary Swart]

Tape vs dope or both together is a discussion that comes up here every now and again. There's really no right or wrong answer, just whatever seems to work best for the individual. I happen to prefer dope alone, but I'm just a bit old school on somethings, so I'm not on a soap box about it.