Can't remove the immersion

[AdamW]

I am trying to renew my immersion heater at the moment. I am using a box-type spanner, the one with the built in tommy-bar. The cylinder is lagged so the standard type isn't an option.

I tried to get the immersion out, it wouldn't budge, so I squirted loads of WD-40 around it, every 30 minutes or so for a few hours. It STILL won't budge. I have even tried whacking it sharply with a hammer to try and loosen it. When I whacked it I heard what was probably limescale dropping off the element into the tank. Either that or bits of the element falling off!

I am putting so much force into it that the hot cylinder actually MOVED. Should it even be in that tight?!

Any ideas on how I can get the old immersion out, I don't want to replace the whole cylinder funnily enough!

 

[oilman]

You need a cast iron ring spanner, they're specially made for the job. One smart wack and it's off.

 

[AdamW]

Would that help? I have been using something like this:

I tried whacking the tommy bar sharply.

They do screw in the conventional direction, right?

 

[AdamW]

Sometimes to solve a problem, all you need is a bigger hammer...

Big whack with a 4lb sledge hammer and it shifted! No evidence of PTFE on the threads, and no fibre washer. So it may have been overtightened by someone to stop a leak.

I will try to post a picture of the old element sometime, the sheath had gone so the live element was exposed to the water

I think I buckled the cylinder slightly in the process. Will be watching VERY carefully for leaks.

 

[oilman]

Cast iron spanners are not at all springy, and they transmit the shock better.