Dielectric Union

Dlarrivee

Dlarrivee

New Member
Messages
1,150
Reaction score
0
Points
0
Location
Canada
Is it a good idea to use dielectric unions on hot water tanks?

Rather than 1/2" copper FIP adapters?
 
Where do you get plastic inserts???

I use copper FIP adapters instead if dialetric couplings...
 
What happened to just using good quality brass nipples?

All this dielectric rubbish.

Brass is best!

dielectric-union-4-years-old.jpg
 
dielectric

Di-electric unions are strictly "cosmetic". They look good and make inspectors happy, but do NOTHING to prevent the electrolytic action, since that occurs through the water, just like the anode rod does to prevent corrosion. Most rusty hot water problems are caused by corroded di-electric unions OR dielectric nipples which can have the same problems.
 
Well I could care less if it was dielectric or not, I'd just prefer any type of union, over having a soldered on one side and threaded on the other fitting.

What is the point of a threaded fitting that can't be threaded off?
 
I believe local code vary widely on how to make the transition for water heater to supply lines, so you need to check with you local code enforcement. In my area, the common way to make this connection is a brass nipple out of the tank (both hot and cold) Then a short length of flexible copper tubing into a male adapter on the water supply. I know some places require a solid connection, so do check you local regulations.
 
heater

IN any case, a direct connection between the copper and steel of the heater is NOT advisable. That combined with water, (water being the key component), IS the formula for elecltrolysis to occur. A 6" brass nipple is the most effective separator.
 
hj said:
NOt if they are installed properly so they DO NOT leak.
Click to expand...

It's still goofy. There is no need for this. If people do it planning on having to remove the tank I'd ask why they plan on removing the tank. And if they think doing that will make the tank easier to change out in 12 years when it fails they're hoping the new tank is the EXACT same dimensions as the 12 year old model.

Dialectric unions are much more expensive then a 3/4 cu x 3/4 FIP barstock fitting. If if you have to cut the tank out a few times the extra couplings you might want to account for are still cheaper then 2 dialectric unions.

Not only that but if you have them on a gas tank they're going to be obstructing the draft hood a little bit.

It's just my opinion but to me have two unions right on the top of a domestic HWT looks mickey mouse.
 
I have worked in a one inspector town that he wanted me to use flex copper and a brass nipple between flex and solid cooper. He didn’t care how I connected the flex copper to the steal tank.
 
Hj is %100 right....unions suck

hj said:
IN any case, a direct connection between the copper and steel of the heater is NOT advisable. That combined with water, (water being the key component), IS the formula for elecltrolysis to occur. A 6" brass nipple is the most effective separator.
Click to expand...


http://www.brasscraft.com/Products.aspx?Id=227

Dialectric unionis are a total joke...they dont do nothing...


Try out These black brass craft connectors some time

they are the absolute best way to go
and I feel that they are have all around better dialectric
properties and you can certainly knock the job out fast

I have a bunch out in the field since 98 and
still chugging along very well ......
Wont know for another
good 5 years on how much they actually increase
the life of the heater... but Iknow they wont clog up on top

some like the plumbing to look straight and uniform
and that is the only downside to them....

Prod_WaterHeaterConn.jpg
 
Last edited:
master plumber mark said:
Dialectric unionis are a total joke...they dont do nothing... Try out These black brass craft connectors some time they are the absolute best way to go and I feel that they are have all around better dialectric properties and you can certainly knock the job out fast
Click to expand...
I use Bradford water heaters with the nipples already in the top of the tank. Mark, have you seen these?
[/QUOTE]

shark.jpg
 
flex

My experience with stainless steel flex hoses is that they will kink before you can make a tight turn with them. The corrugated copper is MUCH better.
 
I only use solid copper pipe to my WH because I enjoy the craftmanship of doing everything that way. And it looks straight and uniform.

Even the gas, I like that hard piped.

I only trust flexible connections on my faucets.
 
plumbernj said:
I use Bradford water heaters with the nipples already in the top of the tank.
Mark, have you seen these?
Click to expand...


the blackones from Brass Craft are much better then those SS ones..

I think those you have posted with the shark bites cost about 18 bucks each ...

my black ones are about 8
 
You must log in or register to reply here.

Similar threads

S
Dielectric union or brass union with brass nipple?
Replies
0
Views
368
steven712
S
rebarman
What is the correct way to transition from galvanized steel pipe from the meter to copper water pipe in a house?
Replies
2
Views
1K
rebarman
rebarman
D
Sweat by Sweat Union with O-ring/Gasket [?]
Replies
0
Views
486
dpoma
D
wmn
Expansion tank due replacement
Replies
8
Views
3K
wmn
wmn
M
Persistent leaky water heater inlet
Replies
2
Views
1K
Reach4
Reach4
Back
Top