Cooker fuse size
- Thread starter gemshan1
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13 amp in what? The fuse/mcb should be a 32 amp.
The 13 amp is overloaded, an rcd doesn't detect an overload.
Do you mean you have a fused spur with a 13A fuse in it protecting a 2g socket ?
Yes I think you are right, both cooker and hob are wire to a 13amp spur switch!!! Having just checked out cooker switches on screwfix I’m now assuming the Muppet that wired this up used the wrong switch? Please correct me if I’m wrong?
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What circuit in your consumer unit is the fused connection unit a part of ? Can you show us some pics ( full consumer unit showing all circuit breakers)
Who is “the muppet” ?
You're never going to be able run both an oven and a hob from a 13A spur - as you have discovered, if you switch both on at once (well over 13A total) the 13A fuse will blow. I presume that what you describe has always been the case whilst the appliances have been wired in this fashion?
You need a (probably 32A) 'cooker circuit' to supply the oven + hob.
Kind Regards, John
Ok here’s a picture of consumer unit, oven written on breaker switch, the hob and oven are wired to a 13amp spur switch which is then wired to the consumer unit, this is all becoming clear to me now that maybe someone has used a 13amp spur instead of a cooker switch? so can I assume that it’s safe to replace this 13amp spur with both hob and oven wired to a suitable cooker switch?
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Is the fused connection unit connected to that circuit marked " oven" ?
If you flip that breaker to off ,what no longer works in the premises ?
If you flip that breaker to off ,what no longer works in the premises ?
Yes it is, flip it off and the oven and hob are off.
If, per terryplumb's question you can confirm that breaker labelled 'oven' is supplying the oven+hob, (via that 13A FCU ('fused switch') then yes.
You would probably need a cooker control unit ('cooker switch') and also a 'dual output plate' (one output for oven and the other for the hob).
Kind Regards, John
If you work out the total load then we can help you decide what tge circuit should be from start (the fuse or MCB in the consumer unit) to finish (how you have the loads connected via switches).
As you starter for ten lets give an example just by way of illustrating a bog standard traditional cooker type circuit.
A free standing cooker with 4 rings for pans and an oven and a high level grill would usually be in the region of 13kw total power.
We do a little bog standard calculation and work out that its perfectly acceptable to use a 30A rewireable fuse at the consumer unit and 6.0 T&E cable for the circuit.
It does not matter if the rings are as a hob and say a double oven is a seperate unit the effect is still the same in a normal domestic household.
Indeed the circuit might be fed from a 30 or 32amp MCB instead of the rewireable fuse in which case you could use 4.0 T&E cable but many would still use 6.0 as old habit die hard.
In the old days people did not have enough sockets so the cooker control unit often contained a 13amp socket which was just intended for occasional use of a kettle and not really for a longer/heavier load such as washer or dryer or a dishwasher etc.
If you actually do the calculation and work out the total load possible then you might worry that 13 or say 15Kw will in fact draw more than 32 amps at our rated voltages but we are allowed on this type of circuit because in real life the rings and ovens all pop on and off because thermostats regulate heat on/off/on/off all of the time after the initial warm up and if a kettle is connected it might be 10amps max for a few minutes only so we reckon okay we will allow 5 amps for that then.
It looks like you have got some kind of set up like the one i mentioned perhaps but with a 13 amp fuse running the whole lot, that is way too small for the loads you are intending to run but get a pro to check out the circuit to see if it is feasible to alter it or if it needs completely rewiring to make it safe.
It is not a job to be done without sufficient skill and knowledge.
As you starter for ten lets give an example just by way of illustrating a bog standard traditional cooker type circuit.
A free standing cooker with 4 rings for pans and an oven and a high level grill would usually be in the region of 13kw total power.
We do a little bog standard calculation and work out that its perfectly acceptable to use a 30A rewireable fuse at the consumer unit and 6.0 T&E cable for the circuit.
It does not matter if the rings are as a hob and say a double oven is a seperate unit the effect is still the same in a normal domestic household.
Indeed the circuit might be fed from a 30 or 32amp MCB instead of the rewireable fuse in which case you could use 4.0 T&E cable but many would still use 6.0 as old habit die hard.
In the old days people did not have enough sockets so the cooker control unit often contained a 13amp socket which was just intended for occasional use of a kettle and not really for a longer/heavier load such as washer or dryer or a dishwasher etc.
If you actually do the calculation and work out the total load possible then you might worry that 13 or say 15Kw will in fact draw more than 32 amps at our rated voltages but we are allowed on this type of circuit because in real life the rings and ovens all pop on and off because thermostats regulate heat on/off/on/off all of the time after the initial warm up and if a kettle is connected it might be 10amps max for a few minutes only so we reckon okay we will allow 5 amps for that then.
It looks like you have got some kind of set up like the one i mentioned perhaps but with a 13 amp fuse running the whole lot, that is way too small for the loads you are intending to run but get a pro to check out the circuit to see if it is feasible to alter it or if it needs completely rewiring to make it safe.
It is not a job to be done without sufficient skill and knowledge.
Ps there are other things i have not mentioned RCDs and bonding for a start
If, as seems to be the case, the 13A FCU is fed by that B40 (labelled 'oven') then it appears to be RCD-protected ... but who knows what cable has been used for the circuit?
As for 'bonding', are you referring to main bonding for the installation as a whole, or what?
Needless to say, I agree with everything you say in your previous post.
Kind Regards, John
My advice to you is find a local spark to come and sort out the oven circuit properly for you. Randomly changing components to what you think is corrrect isn’t a great strategy.
And get them to look at the consumer unit / labelling as that doesn’t bode well for the rest of the installation either
And get them to look at the consumer unit / labelling as that doesn’t bode well for the rest of the installation either
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