Any advice with this immersion?

[KATHLEEN OBYRNE]

I had hot water coming out of cold taps, and the hot taps water was boiling hot. Presumed this was a faulty immersion thermostat. I opened the top cap to take a look at thermostat to see which one I needed, and noticed the wiring for the brown part seemed loose and not connected at all anymore. It just looks like a plastic part has broken. Is it OK for it to be like this and do a straightforward thermostat replacement, or will I now need to change the whole element because that brown part is no longer attached? FYI one brown wire from that loose part goes into the thermostat and the other brown wire is connected to the mains, it is just the housing that is loose.

20220214_102959

• KATHLEEN OBYRNE
• 14 Feb 2022

Should this be attached?

20220214_103009

• KATHLEEN OBYRNE
• 14 Feb 2022

 

[JohnD]

I don't find the pic clear, but it looks like the thermostat has broken off and has water damage from a leaking element. This can be very dangerous. You should get a plumber to fit a new immersion element, which will include a modern thermostat and an overheat cutout. Measure the height of your cylinder as this affects the length of element needed.

Removing an old element takes some experience and skill so a wrinkly old plumber is more likely to be successful than a DIY or handyman.

Please turn off the circuit at your consumer unit until this is done.

The loose brown wire appears to be the incoming supply and would be dangerous if it was touched, or if it touched the cylinder.

 

[bernardgreen]

That is an essential safety device. It turns of the immersion heater if the water comes too hot.

Because it has been broken way from the operating pin it failed to prevent the water in the cylinder from over heating.

The element needs replacing BEFORE you use the immersion heater again.

 

[KATHLEEN OBYRNE]

Ok thanks, not the simple job I had hoped. Is it OK for heating to be turned on as long as I leave the isolator switch turned off for immersion? Not sure when I will be able to get hold of a plumber and don't want to freeze

 

[Deleted member 267285]

As above regards safety.

Do you use the immersion for heating the water? Yes you can use the central heating, that immersion has its own circuit.

 

[JohnD]

Do you mean a gas boiler? Yes you can use that, but turn off the immersion circuit.

Stand back and take a full pic of the cylinder and its surrounding pipes and cables.

 

[KATHLEEN OBYRNE]

Not a gas boiler, I live in the countryside so have oil fired central heating.

 

[JohnD]

Oil boiler is also OK

It looks like the boiler can heat your cylinder, in which case you will still have hot water.

 

[KATHLEEN OBYRNE]

Yes if I turn on my heating it heats up the water. Or if I don't want my heating on, I can turn on water separately. Are you saying I can still have heating on (and the hot water with it), but until I get the element changed, I just can't heat water independently?

 

[JohnD]

Your boiler might be able to heat the cylinder independently of the radiators.

Turn down your room thermostat and see.

 

[Justin Passing]

I just can't heat water independently?

Not quite -
The electric immersion heater is normally just a backup if the oil boiler fails.

You can still use your oil "heating" system on Hot Water Only.

 

[Dereekoo]

The bit thats broke off, was it connected to a rod that went down a hole in the immersion top, if so can you pull this rod out, this will be the actual thermostat that controls the heating? Something like this Tesla Dual Safety Thermostat 11" | Immersion Heaters | Screwfix.com

 

[Dereekoo]

.

 

[Deleted member 267285]

Sounds like a common oil setup, like a c plan, only have hot water when heating is on.

 

[KATHLEEN OBYRNE]

The bit thats broke off, was it connected to a rod that went down a hole in the immersion top, if so can you pull this rod out, this will be the actual thermostat that controls the heating? Something like this

No, the thermostat itself was intact. Just the brown wire feeding into it on one side comes from a brown unit that is no longer attached to the immersion. I am holding the bit that is loose. It is supposed to connect to the circular bit beside the thermostat with the white rod in the middle.