What amp fuse do I need for a storage heater ?

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I have a couple of night storage heaters protected by a separate consumer unit with 15amp fuses protecting each heater.

I am having some grief with one heater which keeps blowing a fuse - question as the heaters are on full pelt at this time of the year is a 15 amp fuse too little or should I replace with a 30 amp ?

I am aware that there may be a fault with the heater but just thought I would ask whether a 30 amp may suffice
 
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That entirely depends on the rating of the storage heater (should be a plate on it somewhere giving a rating in kW), and the size / installation method of your cabling. If it's worked in the past on a 15A, and is now failing, it implies that there is a fault - it must be a fairly severe fault to blow a 15A rewireable fuse (I'm assuming that's what you mean when you say fuse, and not an MCB (miniature circuit breaker).

Also, note that changing the protection method for a circuit (which uprating the fuse would be) is notifiable work under Part P in England and Wales...
 
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Not sure of the rating - it's one of the large size storage heaters with 4 elements and 16 bricks. The fuses are currently 15amp cartridge type - I do have some 30 amp cartridges which I thought I would put in and see if that would do the trick
 
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You can't just simply uprate the fuse like that. If the cabling to the heater is not rated for the current, it could overheat, and melt, potentially causing a fire...

Also, if the heater does have a fault, while the 15A is just blowing, with a 30A it might not blow, causing some part of the heater itself to melt / burn, again potentially causing a fire...
 
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What he said, but in huge letters with knobs on.

You must NEVER replace a fuse with one of a higher rating than the intended in order to stop it blowing.
 
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Thanks for that Rebuke - guess swapping a 15 amp for a 30 amp may not be such a good idea then. Suppose I will have to take the heater apart to see if there is anything obvious. I wonder whether it could be a fault in the consumer unit ! - I do have a spare new c/u identical to the existing one - perhaps I could swop that over - suppose it would be safe to do that in the daytime as there wont be any current going to it as it serves the storage heaters only and hence aint live during the day ! As an option perhaps I could wire the heater up direct to a 13 amp plug and run it off a time switch plugged into the ring main - if that works it would point to the cu being at fault
 
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What he said, but in huge letters with knobs on.

You must NEVER replace a fuse with one of a higher rating than the intended in order to stop it blowing.

Agree - but how am I to know whether the 15 amp fuses fitted are correct anyway ?? - perhaps they are too low a rating !
 
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perhaps I could swop that over - suppose it would be safe to do that in the daytime as there wont be any current going to it as it serves the storage heaters only and hence aint live during the day

VERY DANGEROUS ASSUMPTION

ISOLATION is essential. Not just relying on a time switch.

And to be honest as you thought of changing to a larger fuse you appear to not yet have the basic essential knowledge required to do the work you are suggesting you might attempt.
 
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The way to determine the correct rating fuse is to find out what the load is rated at (as I said there should be a plate or similar on the heater itself, alternatively if it has a model number you might be able to find a manual on the web or whatever), and then verify that the cabling is appropriate for that load. To do this properly would require test kit to work out the EFLI value for the circuit etc.

As for replacing CU - it's unlikely to be a fault with the CU, and if replacing the whole thing, you would have to replace it with a new style CU with MCBs in, rather than cartridge fuses. Again, if in England or Wales this is notifiable work under Part P, that would need to be notified to your LABC before doing anything.

I suspect you would be better off getting a qualified electrician in, who can take a look, use appropriate test equipment etc and at least confirm for you what's wrong - the solution is not to swap bits out and see if it makes a difference...
 

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are you sure there is nothing else fed from that circuit? Has someone added a extra heater, for example?
 
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Agree - but how am I to know whether the 15 amp fuses fitted are correct anyway ?? - perhaps they are too low a rating !
1) They are all the same.

2) All the others are OK.

3) Even if someone has at some point put a larger heater in place of the original there's still the fact that the cable won't be (99.999999999999999999999999999999999999999999% certain) OK on a 30A fuse.

4) Just what basis is there for the first 10 characters of your user ID?
 
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For the fuses to keep blowing in the cu am I right in assuming that the likely causes are either a burnt out element or a faulty thermostat in the heater ? or what else ??
 
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..........and are dimplex elements compatable with a sunhouse storage heater ??
 
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electricalkid, FIND OUT WHAT RATING YOUR STORAGE HEATER IS!

Then buy a cheap clamp meter and see what current its circuit is drawing.

Establish for certain that that fuse powers nothing else. (Immersion heater for instance)

If you can do none of the above, CALL AN ELECTRICIAN.
 

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