Dielectrics on new HWT

[John7]

I just bought a new electric hot water tank. It came with pre-installed dielectric (DE) steel nipple on the hot outlet. This unit has the cold inlet at the bottom and uses a brass combination tee and drain valve. There is no dielectric provision here. Also the brass temperature relief valve is screwed directly to the steel tank.

Q1. Don’t these also need dielectrics? I am replacing the combination tee and drain valve with a proper steel dielectric nipple, brass tee, ball valve etc.

Q2 I am reinstalling the relief valve on a steel dielectric nipple. Should this and the cold inlet have an actual dielectric union? (FWIW elsewhere, the boiler manufacturer said they would void the warrantee without proper DE unions. The ones with a plastic separator and BRASS, not steel, on the copper side.)

Q3. In general do normal installations of copper/brass directly to these steel DE nipples not corrode? (It seems the DE nipples only protect the tank, not the copper/brass to steel interface).

Thanks

John

 

[Terry]

Brass installed on a water heater is fine.

In some locals, they prefer brass between rather than what is called a delectric union. Which by the way, I won't install. The unions are useless.
In the Seattle area, because of earthquakes, they like to see flex connectors. I use copper, but some use stainless steel.

 

[Sponsor]

 

[Dj2]

1. Dielectric or brass - your choice.

2. A union (choose brass) on the P&T valve is OK but not essential.

3. In most cases, but not in 100% of the cases, copper to dielectric will not rust.

 

[hj]

Unless the T&P valve has a female inlet you CANNOT connect it to the heater with a dielectric nipple because its probe MUST be inside the tank, nOT inside a dielectric nipple.