Scalding/dangerous hot water from immersion heater

[ivrytwr3]

We moved into our new home yesterday (1999 build) and found there was no hot water. In the end we contacted the previous owners who informed us the heating is ran by the boiler (working fine) and the hot water is ran by the immersion heater which they left swotched constantly on.

We turned on the immersion heater (top part, as there is a top switch and bottom switch). A short time later we had hot water - yey!

However, at 2am, there was loud bubbling noises coming from the tank and the loft. I immediately turned off the immersion heater and found:

1. Pipe coming from top of immersion too hot to touch.

2. In loft the tank was bubbling like a boiling kettle and steam was coming from it.

3. When i turned on the hot water, it was scalding hot - no kidding, i couldn't touch it (you could have made a cup of tea with the water!)

I drained off some of the water through the taps and fortunatley we are all still alive this morning. I cannot find a thermostat anywhere, so can anyone advise what has happened? Do we need to get an engineer out?

(sorry for questions, but previous owner has not left any instruction manuals for system!)

Here are some pics of the system:

 

[Rosebery]

Cylinder is already indirect by the looks of it.

 

[ivrytwr3]

ok, i've took the thermostats out and now have 2 x BT7 thermostats. On the net i have found these:

[DLMURL="http://www.theelectricalcompany.co.uk/search.php?xSearch=bt7"]The Electrical Company > The Electrical Company > Electrical supplies[/DLMURL]

Are these OK to use? Or can anyone recommend a better one?

Also, when i took them out, there were 2 wires going into the thermostats, 1 white, 1 grey. When replacing the thermostats does it matter what goes where? ie is it like a 3 pin plug, live, neutral etc?)

 

[GrahamM]

I would stop right there and get someone qualified to do the job.

 

[ivrytwr3]

lol, why? everyone is telling me how simple a job it is!

 

[TC.]

it may be a simple lookng job but if you screw it up you could end up causing alot of damage to either the building or a person through the spillage of scalding hot water.

you should get a plumber in to do this job.

 

[ivrytwr3]

too late now, i'm half way through the job!

I took the thermostats out to have a look at them, sizes any obvious damge, make sure i order the exact replacements etc. My question is, when i get the new ones, i am unsure as to which sides the 2 x wires (white and grey) go into. Is it like a 3 pin plug and they come with a wiring diagram?

Any help/pictures would be very much appreciated.

 

[GrahamM]

No one here should or would condone you messing about with electrical connections for which you have little knowledge of.
No one knows how this is wired up without looking at it and doing the relevant electrical checks to confirm it has been done correctly.
This is a bit more involved than sticking a plug on a toaster and has the potential to be more dangerous if done incorrectly.

I'll say it again, call a competent person to finish what you started.

 

[ivrytwr3]

Had an Eon engineer at my place today to change the meters over. I asked if if he did 'private work' and we spoke about changing the thermostats - he said if i could change a plug i could change the theromostat.

And on here and diy.com, people have advised it's a simple task.

My only concern now is, on the thermostats i have taken out, there are 2 x holes/screws for connecting them to the element/tank - and i have 2 x wires, one grey and one white, but there are no markings on the thermostat as to which wire goes where.

So my question is, does it matter which way it is wired, if it does, which goes where!?!

But thanks for the warnings.

 

[ivrytwr3]

no one? i'm stuck now then; lol!

 

[ecowarm]

no one? i'm stuck now then; lol!

Where in lincs are you?

 

[ivrytwr3]

LN4 (coningsby/tattershall)

 

[ecowarm]

Im in N e lincs and I dont have any jobs that way at the moment but will send my phone number by PM

Eco

 

[ivrytwr3]

pm returned - thanks