Problem Installing Dielectric Unions on My New Water Heater

[skeezix]

I bought a couple of 3/4-inch dielectric unions to use with my new water heater. The ends are 3/4-inch male pipe thread. And the 3/4-inch nipples that came installed in my new water heater also terminate with 3/4-inch male pipe thread. I would like to remove the nipples and screw the unions directly to the heater. I tried to remove the nipples from the heater by using a 13-inch pipe wrench but the they just will not budge! (And I can't keep the tank from turning either.) So I thought I would buy a couple of female-to-female adapters but before I do I would like to ask here if somebody knows any tips to removing those nipples.

The tops of the nipples have a blue plastic thingy inside and the one on the intake side has what looks like a restrictor inside. If I have to leave the nipples attached can I take the restrictors out or do I leave them in?

 

[Jeff Handy]

Leave the dielectric nipples in there.
They will not choke up inside from corrosion, which will reduce flow rate.

And trying to remove them can damage the glass lining on the tank.

Buy different unions, dielectric or not.

PS I thought you already sweated on these unions, referenced in a different thread.

I would remove the heat trap inserts on the top of the nipples, but that is a personal preference.

 

[SHEPLMBR]

They make FIP (female) dielectric unions. Take the males back and get those.

 

[skeezix]

This is what comes out of the new tank:



I don't think the blue part comes out. At least I don't know how to remove it. It does have a restrictor inside of it.

And this is what I bought at Lowes:



I don't think that Lowes has unions with female threads.

 

[SHEPLMBR]

Ask them or go to a plumbing supply or another hardware store. Adding a brass coupling would be useless and redundant. Those nipples in to[p of the water heater are dielectric. If you want unions just get brass ones and put on top of the nipples.

 

[voletl]

Okay first things first all water heaters come with dielectric nipples installed from the factory there is no need and no reason to install dielectric union on any water heater

Second of all removing that nipple in the water heater will void the manufacturer's warranty
Third most water heater nipples have heat traps inside of them removing what causes heat migration into the cold line.

My advice is to forget the union and pipe directly to the nipple

 

[skeezix]

I want to thank everyone who replied.

I installed the heater without additional problems except...

for a tiny leak (like one small droplet every minute). But that's for another thread.

 

[Jeff Handy]

That tiny leak will very likely stop by itself, in a few hours or a day.
They usually do, no big deal at all.