Immersion heater removal tips

[trevorqpr]

Hi people

I'm going to replace my immersion heater.

Are there any good ways to get them out without damaging the hot water tank. I have heard they can be rather stiff, and would appreciate any tips on how to get it out fuss-free

If anyone can help, please do so

 

[sooey]

I generally just heat them up a bit with my blowtorch, though you have to watch you don't set fire to the insulation. Then a few sharp taps with a hammer on the immersion heater spanner usually gets it.

 

[trevorqpr]

Thanks for such a quick reply.
I have heard the cylinder can split, is this the best way to avoid this?
I have an immersion heater spanner. Well 2, a cranked one and a box type one.

 

[sooey]

An old cylinder that's not in very good condition can split. So could a new one if some big ape just comes along and starts applying brute force to a really tight connection. It's only thin walled copper after all. That's why I like to apply some heat first and then try to shock it loose. Like I said, it works for me, though I use a flat immersion heater spanner.

 

[trevorqpr]

ok I'll try your way! I have a flat one too, in the shed somewhere!

How much heat would you apply, I mean how long for?

Is it good to try and free/get it freed whilst still full, then drain down and remove it?

 

[sooey]

Just give it a couple of minutes with the torch, you only want to get it hot so the expansion and contraction will hopefully help break the "tight".
Leave the cylinder full while you do it and catch any spills in a couple of old towels. It will only be whats in the top of the cylinder that comes out as long as you bung the tank.

 

[trevorqpr]

I'll get it loosened, then drain down a bit to lower than the cylinder level, then undo it and remove it.

Thanks for your help

On the new heater is it ok to just use the washer with it, or is a bit of PTFE tape around the threads advised as well?

 

[sooey]

I wouldn't bother with ptfe, just put a bead of LSX on the washer.

 

[Charnwood]

Oh, not Boss Purple With Red Stripes? (generic term.)

 

[Nige F]

Or - you could leave the system full of water and losen the immersion - the water will keep the cylinder from buckling - then drain down a bit and remove it - save the planet by not lighting your gas blowlamp