Number of appliances on one radial line

Presumably on a 20A MCB?


It does seem slightly mean, but I suspect it's unlikely to give problems in reality. Normally there a fair bit of diversity between kitchen appliances. I presume the boiling water tap is the 13A variety and will only be heating either when the tap is on or occasionally at other times to top up the heat in a stored tank. A dishwasher and washing machine will usually only take full power during the relatively short water heating part of the cycle. A conventional tumble dryer might well take a decent load (10A perhaps) for an extended time - hopefully a modern condensing mode dryer (usually what's in combined washer/dryers these day I think) should take rather less. I suspect the coffee machine would be drawing current for only a matter of a few minutes in an hour on average (and probably a lot less than 13A even then).


A 20A circuit doesn't have an absolute limit of 20A - 20A is what it can supply indefinitely - both the cable and MCB/fuse will be quite happy to supply more for short durations (say 30A for perhaps 10 or 20 minutes - that sort of thing) - so there's little risk if several appliances do occasionally happen to switch on at the same time.


A more conventional arrangement might be a 32A ring circuit (wired with two 20A cables) - but is (as is often the case) it's not well balanced, you can still have a a large proportion of the kitchen appliances' current going through a single 20A cable - and likewise actual problems are rare to non-existent.


If you had an entire kitchen/utility on there - perhaps including an electric oven or two - as well as many more sockets and perhaps separate washer and dryer, I might be more inclined to ask for an upgrade to a 32A circuit. But as stands it's less clear cut. If it were my house I would have put in a 32A radial as a minimum - but then my other half does keep throwing the phase 'never knowingly under-engineered' at me. Ultimately if the builder is working for you, they should be doing things to your satisfaction.


   - Andy.

Presumably on a 20A MCB?


It does seem slightly mean, but I suspect it's unlikely to give problems in reality. Normally there a fair bit of diversity between kitchen appliances. I presume the boiling water tap is the 13A variety and will only be heating either when the tap is on or occasionally at other times to top up the heat in a stored tank. A dishwasher and washing machine will usually only take full power during the relatively short water heating part of the cycle. A conventional tumble dryer might well take a decent load (10A perhaps) for an extended time - hopefully a modern condensing mode dryer (usually what's in combined washer/dryers these day I think) should take rather less. I suspect the coffee machine would be drawing current for only a matter of a few minutes in an hour on average (and probably a lot less than 13A even then).


A 20A circuit doesn't have an absolute limit of 20A - 20A is what it can supply indefinitely - both the cable and MCB/fuse will be quite happy to supply more for short durations (say 30A for perhaps 10 or 20 minutes - that sort of thing) - so there's little risk if several appliances do occasionally happen to switch on at the same time.


A more conventional arrangement might be a 32A ring circuit (wired with two 20A cables) - but is (as is often the case) it's not well balanced, you can still have a a large proportion of the kitchen appliances' current going through a single 20A cable - and likewise actual problems are rare to non-existent.


If you had an entire kitchen/utility on there - perhaps including an electric oven or two - as well as many more sockets and perhaps separate washer and dryer, I might be more inclined to ask for an upgrade to a 32A circuit. But as stands it's less clear cut. If it were my house I would have put in a 32A radial as a minimum - but then my other half does keep throwing the phase 'never knowingly under-engineered' at me. Ultimately if the builder is working for you, they should be doing things to your satisfaction.


   - Andy.