Hot water tank - thermostat issue?

[andyroberts1234]

Hello,

We had hot water coming through our cold taps yesterday - I checked and the cold water tank was also steaming. I assume it is a broken thermostat?

I have turned the immersion off and drained/replaced the water in the cold water tank so no chance of melting.

On checking the boiler, there looks like there is a lot of corrosion (see pics). What concerns me most is the water showing just below the CE mark of the thermostat. Are there any issues with this - can I just replace the thermostat and not worry about any of the aesthetics?

If the whole heating element needs to be replaced, is this an easy DIY job...or one for a pro?

Cheers, Andy

Untitled

• andyroberts1234
• 10 Mar 2015
• 1

Untitled

• andyroberts1234
• 10 Mar 2015
• 1

 

[Burnerman]

You've had a wee leak for a while, it seems......personally I'd replace the entire immersion heater ( with its new gasket) and start again.
Do buy a quality one!
John

 

[Tibbot]

You should replace everything, cylinder, immersion, cable the lot. It's in a sorry state. That may not be desirable or affordable but to me your idea is a bit like trying to recover the ship's biscuit off the Cutty Sark.

 

[Agile]

Its not clear to me from your photos if its the immersion element or something else on the cylinder which is leaking.

You might be lucky and it could be possible to unscrew the element.

I charge about £100 plus the cost of a new element about £30 to replace IF they can be drained easily and IF they can be removed within an hour.

They are not most plumber's preferred jobs on old cylinders and there is always a risk the cylinder will buckle and need replacement.

I only replace elements at the customer's own risk of the cylinder needing replacing.

To replace the whole cylinder is about £460 !

Tony

 

[andyroberts1234]

Thanks for the quick replies!

If it's possible to replace the element for now and be safe then that would be preferred rather than a new cylinder. I will try and get a better look at where the leak is coming from.

Is it possible for me to check whether it is possible to unscrew the element without having to drain the tank (i.e. can I just unscrew it a bit to see if it moves)?

Also, are there any major risks of turning the immersion on for short periods so that some water can be heated, while taking care to not allow it to overheat? Just while we sort out the repairs/replacements?

 

[Agile]

You should first see if it can be turned a few degrees and with the cylinder full to help hold it down and press it out.

You could turn on for shorter times.

But better to buy a new element and borrow the stat and fit that as then you can leave it set to 60 C with a reasonable degree of safety.

But first see where it is leaking !

Tony

 

[Burnerman]

If you try to unscrew the immersion, you run the risk of creating a leak that will be worse than before.
Similarly, if you run the immersion for a while without the thermostat, you need to be sure to turn it off.....not recommended in either case!
Your big issue .....the immersion may unscrew without any bother......on the other hand, it may crease the tank under the pressure of the spanner. It really depends if your luck is in!
John