End feed into HW cylinder question

[WatcherOfCaedNua]

Hello everyone, I have a quick techincal question. The cold water feed into my hot water cylinder has a 22mm T with a drain off. As you can see this has been leaking. My plan was to leave the end feed union connected to the tank, sweat off the T joint, cut the 22mm pipe before the elbow and redo with new pipe.

Or, should I replace the union on the tank as well? I'm guessing they are just compression fittings? no extra seals/gaskets I need to buy?
Thanks

 

[Madrab]

The union into the cylinders are usually a threaded tapping but there are so many different approaches that it could be a formed swaged end that is part of the cylinder and would only be soldered. Hard to say from the pic. I'd start by draining & remove the tee and see whether the elbow is still sound as the heat may affect that too, so it may be an idea to replace that too. Then just re-make all the connections with a new drain off.

 

[fixitflav]

Depending where the leak is, can't you just unscrew the drain fitting and remake the joint?