Immersion Heating Cold Water Tank

pauld

I assume the reason this is happening is that the themostat is bust! correct me if I am wrong.

Question for the experts here is do I call a plumber or an electrician? please tell me I don't need both!

Many thanks

Zynks

Either should be able to do the job IMO. Just in case, have you checked the fuse? Are you able to check if there is power reaching the tank? It should be one of these:

- Fuse at local switch gone - easy DIY job
- The element is gone - harder DIY job, but "outsourceable" to an expert
- No power (maybe the switch at the fuse box has flipped to off)

pauld

thanks for the info- not very up with all that electrical stuff so will give the electrician a call.

to clarify the immersion heats the water in the boiler but it gets way too hot, and for some reason whne this happens the cold water storage tank in the attic reaches boiling point!!! the plastic storage tank made some very scary noises with the boiling water in it - had to turn on all the taps in house to flush out the hot water.

the gas central heating system is heating the water correctly in the boiler and it is not affecting the cold water storage tank in the attic.

thanks again for the quick response

Zynks

My impression in your first post was that the water was not heating. This is a very different scenario, and yes, you original guess about the thermostat is very likely to be correct. An electrician should be able to replace it is a few minutes.

pauld

Zynks apologies for not being clear in my first post - thanks for responding, I will an electrician a call.

thanks again.

davidoco

If this happens when you are not using the immersion then the thermostat strapped to the tank may be busted or just turned up too high. THIS IS ONLY IF IT IS THE CASE that you are not using the immersion to heat the water.

What the thermostat will do is shut off the valve sending the water from the heating system through the hot water cylinder which heats the water you get from the hot tap. You might also have a faulty valve (electricial t junction on pipes) which is stuck open.

A thermostat on the tank can be replaced quite easily.

Try this only if you have a three port valve

Turn stat on hot water tank down to 0
Turn on central heating.
If after 15 minutes you have hot water VALVE is the problem.
turn off central heating
then locate three port valve and pop it off by pressing button on back. It will lift off. holding it in your hand turn the heating system back on or get somebody to do it and watch to see if the actuator in your hand turns or makes a buzzing noise
if not turn off power and disconnect it, go to any plumber supplier, buy the same one and refit. cost 60 euro

rooferPete

Hi pauld,

FWIW, I saw a house flooded because of a similar problem, the difference was the expansion pipe was not letting all the boiling water into the tank.

My recommendation is replace the immersion heater if that is where you think the problem is coming from, in the meantime you can switch off the immersion when not needed.

Even cylinder thermostats can be by-passed by the immersion stat to prevent the water over heating, from what you describe it is possible for a person to be scalded by the water from the hot tap.

Also you should have a lot of steam entering the attic which could damage your insulation as there is more than likely a fair bit of condensation forming on the underfelt.

Replacing the immersion is usually carried out by a plumber.

.