Leak between nipple and union

[Howbadisit]

I installed this Bradford White water heater about 6 months ago and just noticed this corrosion on the galvanized nipples below the dielectric unions. I tried tightening the bottom of the union on the nipple and it started to let a few drops of water through, so I need to take it apart and re-tape/dope the nipples.

My question is whether or not I need to replace these nipples (dip tubes and anode rod I guess is attached to them)? Is the galvanized coating compromised and going to cause a bigger problem if I simply take them apart and put them back together?

 

[Terry]

It's a dielectric union. If you loosen and remove, it should be tossed and a new one installed.

This is what they look like over time.

What they look like when new.

I'm on the earthquake coast, so we use flex lines to the water heater that come with their own unions. Those can stay on a water heater for 20 years and not be a problem. Dielectric unions on the other hand are garbage. If I need to go between galvanized and copper, I use a 6" brass nipple.

These soft copper and also in Stainless Steel lines have their own unions that work better.

 

[Sponsor]

 

[Howbadisit]

I appreciate the response, but do you have any insight about whether the nipple is compromised or if it can be reused?

I'm referring to the nipple on the top of the water heater, it is not a component of the dielectric coupler. I believe on these water heaters the nipple is attached to a dip tube on one port and an anode rod on the other. So I can't just pick up a couple nipples at the big box store.

 

[John Gayewski]

Are you sure that nipple isn't welded to the tank?

 

[Breplum]

Don't worry about the nipple. Right now it is just a thin layer of rust.
Almost all WH have a liner of plastic inside and the new rubber seal from a new stainless steel WH flex will do the trick.
Do not bother with crappy dielectric unions.
For d.i.y. use sharkbite x f.i.p flex.

 

[Howbadisit]

Thanks for all the replies. I got rid of the unions (they were already showing signs of gunk after less than 6 months), and replaced them with copper flex pipes.

 

[PDupuis]

It's a dielectric union. If you loosen and remove, it should be tossed and a new one installed.

This is what they look like over time.

What they look like when new.

I'm on the earthquake coast, so we use flex lines to the water heater that come with their own unions. Those can stay on a water heater for 20 years and not be a problem. Dielectric unions on the other hand are garbage. If I need to go between galvanized and copper, I use a 6" brass nipple.

These soft copper and also in Stainless Steel lines have their own unions that work better.

Hi Terry, do you install the 6" brass nipple directly into to the water heater?