Removing a tight immersion element.

[Stevex]

Got all my stuff together to finally fit the recirculation pump to my hot water tank, but I can't budge the immersion element.
I need this out because a) I'm fitting solar which will be used to heat the hot water and although the fitted element has not been used so far, it's been in maybe 20 years. b) I need to look into the tank to see how low I can fit the recirc pumps return essex flange relative to the indirect heating coil. I also need to drain the tank from this access because the cold feed is hidden behind the tank and doesn't have a drain point!!
With the tank full atm I'm not sure applying heat to the immersion head will work either and although I've read that drilling and cutting to the heads threads can help, it's a path I don't really want to go down.
The hot feed from the top of the tank goes up 45 degrees for a foot before teeing at the vent/hot water tap supply pipe and is soldered. On the 45 degree pipe is another tee feeding the shower, again soldered, which together mean I'm unlikely to be able to pull the pipe out of the top of the tank after loosening the compression joint.
Any suggestions please?

 

[Ben-gee]

Isolate thd feed feed to the cylinder, or drain the cws if necessary.
Immersion box spanner with a long bar through it, tap the bar with short sharp hammer taps - may need to be quite hard…
Do this with the cylinder full, you are only going to crack the immersion loose at this stage and an old towel will be enough.
When it’s moved enough that you’ll be able to undo it it’s time to drain the cylinder.
Undo the hot out from the top of the cylinder and move it aside (I know you think it won’t move , but it will be possible . it always is). At this point you’ll lose some water, towels or a wet vac .
Then poke a garden hose into the cylinder outlet and run it to a bath or wc or to the outside. Give it a little suck to start the syphoning and then leave it to do its stuff. Control the level of the hose within the cylinder to make sure it drains fully.
Then wind out the immersion.

 

[Deleted member 120897]

Agree, but being careful not to split the cylinder

 

[Stevex]

Thanks Ben
Chris...that's my one worry.

 

[Deleted member 120897]

Thanks Ben
Chris...that's my one worry.

Obviously won’t know unless you try

 

[Ben-gee]

Experience is key in this area, you get the feeling for how far you can go before the tank will rip or the boss rips out.

The thing is would you be able to cope if the worst happens? Hint have the hose in place for draining, towels/plastic sheet (depending on layout of surroundings) and a wet vac plugged in and within reach….

Mostly this job goes fine but it’s often a nervy one - and occasionally to be frank a disaster!

Good luck

 

[Knappers]

Tap with hammer on box spanner is the way to go. It's sustained high torque that's going to cause problems so don't 'swing on it'.
You could cut outlet if needed and refit after.

 

[SimonG]

The tap it genuinely works, only had to drill and cut 1 out previously.

 

[Stevex]

Well, tried again with an immersion ring spanner with another large spanner as an extension. As well as bending the arm of the ring spanner I could see the tank element neck distorting so called it a day before I ripped the thing open. Even with the tank virtually full of water I could feel it starting to move, which shows how much force I was giving it.
I also tried hitting the element outer ring with a hammer and chisel, but no luck.
I think I may have to admit defeat and go for a replacement tank...pain in the @rse.

 

[Ben-gee]

Ring spanner is no good, get a box spanner - I think mine is Rothenberger, comes with a sturdy bar which I have extended on occasion.
If you’ve resigned yourself to a new cylinder, may as well go for it - either it undoes and you’ve saved a few hundred quid- or it rips open and you’ve lost nothing.

 

[Chuck]

If possible have a second person around to give you a hand if something goes wrong. I always remember getting a leak that I could stop if I held the towel on it firmly but I'd left the bucket, etc. downstairs and no one was around to go fetch it for me.

TBH, I'm usually pretty cautious but I really screwed the pooch on that occasion. Still get nightmares about it...

 

[Stevex]

Bought a box spanner and eventually got the element moving.
Element out and had a look inside to see where the lower essex flange needs to go. Will do the drilling later
and in the mean time I've refitted the element with ptfe, so it will remove easily next time.