A fuse in my fuse box tripped a couple of times over the space of a few months, this is the fuse labelled as immersion heater, it eventually stopped working so on advice I tried replacing it with a new fuse but this didn't help and the fuse is unusable at the moment. I can still get heating so I don't think it's labelled correctly on the box, nothing seems to have stopped working apart from the fuse. I'm wondering what the problem could be? Please excuse my ignorance but this is my first time living alone and I am totally clueless. I'd like a bit more knowledge of what it could be before getting an electrician out as I don't want to be ripped off.
Help with fuse box problem
- Thread starter Peroxide
- Start date
Hi, slightly confused by your description -
fuses don't trip, mcbs and rcds trip.
What do you mean by 'the fuse is unusable now'?
If the problem in question does relate to the immersion heater, it may be that the heater itself has some sort of problem.
Does the immersion heater have any sort of switch near by it to? (hoping it does and also have an indicator lamp included)
Do you have the ability to upload a photo or two of the fusebox/wiring close to the heater?
fuses don't trip, mcbs and rcds trip.
What do you mean by 'the fuse is unusable now'?
If the problem in question does relate to the immersion heater, it may be that the heater itself has some sort of problem.
Does the immersion heater have any sort of switch near by it to? (hoping it does and also have an indicator lamp included)
Do you have the ability to upload a photo or two of the fusebox/wiring close to the heater?
You say you are still getting heat are we talking central heating or hot water?
What amp rating is the protective device and is it MCB, Fuse or RCBO?
There does seem to be a fault on a circuit somewhere, it could well be a disused circuit, where the fuse was never removed, but it could be circuit that you have not realised yet, that it is not functioning. Such as an outside light, external socket, a small radial for socket within the house, under cabinet lights etc...
Have you tried every socket for power.
What amp rating is the protective device and is it MCB, Fuse or RCBO?
There does seem to be a fault on a circuit somewhere, it could well be a disused circuit, where the fuse was never removed, but it could be circuit that you have not realised yet, that it is not functioning. Such as an outside light, external socket, a small radial for socket within the house, under cabinet lights etc...
Have you tried every socket for power.
Oh, BTW. Just calling an electrician round does not mean you are going to be ripped off.
Contrary to some peoples belief, not all tradespeople are out to empty the purses of Joe/Joanne Public.
Why don't you ring 2 or 3 local sparkies, give them a brief idea of what you think the problem is and ask them for some indication of what charges may be involved. (This will probably involve a bit of guesswork on their part as nobody yet knows what the actual problem is)
Contrary to some peoples belief, not all tradespeople are out to empty the purses of Joe/Joanne Public.
Why don't you ring 2 or 3 local sparkies, give them a brief idea of what you think the problem is and ask them for some indication of what charges may be involved. (This will probably involve a bit of guesswork on their part as nobody yet knows what the actual problem is)
It's an MCB 16amp, I'm still getting heat to the radiators and the water, though I do think there could be a problem with the switch in the airing cupboard which deals with switching on water/heating as the button that switches on the heating doesn't work properly when I press the button, though the heating is programmed to come on at set times and works.
I will try ringing an electrician, I was just worried about a big call out fee as I also have to pay for a new fence to be put up next week as it blew down in the wind, great start to the year!
Thanks for trying to help, I know I've been vague, it's something I've usually relied on other people in the house to deal with, so I've picked up no knowledge on the subject.
I will try ringing an electrician, I was just worried about a big call out fee as I also have to pay for a new fence to be put up next week as it blew down in the wind, great start to the year!
Thanks for trying to help, I know I've been vague, it's something I've usually relied on other people in the house to deal with, so I've picked up no knowledge on the subject.
My major concern is that you, in your own words, who is totally clueless, have opened the Consumer Unit disconnected the old MCB, fitted and then connected the new one and now it doesn't work. 
If you think that the MCB you replaced belonged to the immersion heater but the radiators and the tank are still getting hot then, have you got a standard gas central heating/water boiler? If you haven't and the tank is getting hot then the MCB for the immersion heater is not broken its working fine.
If you think that the MCB you replaced belonged to the immersion heater but the radiators and the tank are still getting hot then, have you got a standard gas central heating/water boiler? If you haven't and the tank is getting hot then the MCB for the immersion heater is not broken its working fine.
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Please remember this is a guess and could be wrong. I will guess your hot water is being heated by the central heating and the immersion heater is a stand-by should you not be using the central heating. In which case knowing if the immersion heater has failed is not that easy to work out.
I will guess the immersion heater has failed and likely needs replacing and there was nothing wrong with the MCB you replaced.
Renewing an immersion heater is not easy. Many a tank has been ripped trying to change the immersion heater and also there are two types one where it's the only form of heating has a thermostat which should it fail can't be re-set the other for when is a secondary form of heating with a re-settable thermostat but the latter can only be used when the header tank is on a type which will not fail with boiling water.
The question is who to call. Plumber or Electrician? As an Electrician I would disconnect the immersion heater but would not change it as my insurance would not cover me should anything go wrong. So all I can advise is say you suspect a faulty immersion heater and select some one willing to do all the work not just part of it.
I will guess the immersion heater has failed and likely needs replacing and there was nothing wrong with the MCB you replaced.
Renewing an immersion heater is not easy. Many a tank has been ripped trying to change the immersion heater and also there are two types one where it's the only form of heating has a thermostat which should it fail can't be re-set the other for when is a secondary form of heating with a re-settable thermostat but the latter can only be used when the header tank is on a type which will not fail with boiling water.
The question is who to call. Plumber or Electrician? As an Electrician I would disconnect the immersion heater but would not change it as my insurance would not cover me should anything go wrong. So all I can advise is say you suspect a faulty immersion heater and select some one willing to do all the work not just part of it.
My major concern is that you, in your own words, who is totally clueless, have opened the Consumer Unit disconnected the old MCB, fitted and then connected the new one and now it doesn't work.
If you think that the MCB you replaced belonged to the immersion heater but the radiators and the tank are still getting hot then, have you got a standard gas central heating/water boiler? If you haven't and the tank is getting hot then the MCB for the immersion heater is not broken its working fine.
I actually asked my boyfriend to fit the new MCB, thinking maybe it had blown but we had the same problem with the new one.
The MCB is marked up as immersion heater, so I assumed it would be correct, maybe it's not. My heating/boiler is standard but not a combi.
If it's heating the water in the hot water cylinder it would be a standard boiler, not a combi.
As said - the likeliest situation is:
You have an immersion heater as a standby, and this has failed. You still have hot water because the boiler is working. There was nothing wrong with the old MCB, nor with the new one.
You need a new immersion heater.
As said - the likeliest situation is:
You have an immersion heater as a standby, and this has failed. You still have hot water because the boiler is working. There was nothing wrong with the old MCB, nor with the new one.
You need a new immersion heater.
And if/when you call the electrician don't say it's an emergency or urgent (if, I presume, it isn't) otherwise you may incur a callout charge. Just ask for it to be looked at as a normal job. If they try and charge you for an emergency callout tell them to go away.
Likely - but not necessarily.
Some plumbers/people advocate retaining the HW cylinder as smaller combi-boilers are a bit weak for filling baths.
Seems a waste (of space and energy) to me.
Another thought.... do you have somewhere a box with buttons on it for 1 hour, 2 hour etc?
It may be that this circuit is used as a booster for the immersion tank.
It could be that the normal power to the immersion is fine, and heats using off-peak power, and this circuit is the booster, for if you run out of hot water. It connects to the above mentioned box.
That would explain it being marked as immersion, but you still get hot water when it trips. So maybe this circuit is faulty.
The box sometimes has a label on it saying BX2000, or 'immersion controller'
It may be that this circuit is used as a booster for the immersion tank.
It could be that the normal power to the immersion is fine, and heats using off-peak power, and this circuit is the booster, for if you run out of hot water. It connects to the above mentioned box.
That would explain it being marked as immersion, but you still get hot water when it trips. So maybe this circuit is faulty.
The box sometimes has a label on it saying BX2000, or 'immersion controller'
I'll have a look when I go home but I don't think I do.
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