Power For Dishwasher

[Jeff Gaines]

I want to have a dishwasher installed, should be straightforward there is space next to the sink and a spigot in the waste. The plumber said he would drill a hole in the work-top to run the power cable up to an existing socket. Not sure I'm overjoyed with that. Could a socket be spurred off the existing ring or should it actually be on the ring? Ideally I'd like a switched spur unit above the work-top feeding a socket underneath so I can easily turn it off when necessary.

[Owain]

It can be spurred off the ring, provided the existing socket is on the ring and is not itself a spur. Note that 2 cables do not guarantee the socket is on the ring as under previous regulations it was permissible to run two single sockets as a spur.

Owain

[Tabby]

any water getting in there, as it does, will cause the top to swell and break up.

either

hope you've got spare tiles, if the wall above the worktop is tiled.

Is there really nowhere you can run the cable to horizontally on an extension lead? Would avoid any work.

NT

[Bob Eager]

That's exactly how I did it (your 'Ideally').

[John Rumm]

Yup, a bit of a bodge really.

Yup that would be fine if the socket is on a ring. Adding a switch (with neon of you want) to control an unswitched single socket beneath the worktop is the most elegant way.

[ARWadsworth]

A plumber? - tis a DIY group Jeff:-)

I take your point about wanting a proper job doing, however it may cause some damage to the tiles etc. There is no reason why the socket needs to be on the ring, a spur will be fine.

The plumber is probably not part P registered and therefore unable to legaly do what you want. ISTR that you were getting an electrician in to change your fuse box. Why not just run the dishwasher via an extension lead without drilling the worktop until you get your electrician in?

Cheers

[Martin Pentreath]

I know this is the standard "ideal" solution in here, but I don't think extra switches around the kitchen are particularly elegant. I put my dishwasher, microwave and fridge in with no means of isolation other than pulling them out and switching off the socket behind the machine. They've all been in around four years now, and I've never yet had to turn any of them off. Elegance apart, pulling an appliance out once every four or five years is a hell of a lot easier than chasing out the wall and retiling ;-) In the highly unlikely event that they burst into flames I would much rather run out of the kitchen and turn everything off remotely from the fusebox!

[js.b1]

Electrician's guide to BR is appliances built-in should have isolator above, however appliances not built in do not need a separate above worktop isolator.

It is better to have a 32A/45A DP switch for that circuit, eg, one for all sockets (32A ring or radial), one for all appliances (32A ring or radial), one for electric cooker (32A or 45A). Much better in case of a fire, it can be useful to have the cooker hood off the lighting circuit so you can flick the cooker hood on max to get rid of smoke whilst you find a fire blanket or extinguisher (shutting the door on an oil fire is a pretty quick way of being overcome by fumes).

Whilst kitchens should not have a smoke alarm, instead a heat alarm, I am coming around to the view that a separate non-interlinked battery powered smoke alarm with hush button is a good idea. Very easy for a tea towel to get too close to a hob, or toast to burn, toaster to stick (when will kitchens get a fire panel on the underside of the cupboard above??).

[ARWadsworth]

Personally I cannot stand switches above the worktop.

I usually just install the socket in the cupboard next to the appliance (unless the customer wants a switch above the worktop) That allows the appliance to be isolated without moving it.

The vast majority of sockets in peoples houses are hidden in some way (behind TVs, sideboards, bedside cabinets etc) and the only domestic appliance that needs an accessible switch for emergencies is an electric hob.

[John Rumm]

The difference between kitchen white goods and TVs etc, is they are often rather difficult to get past to reach the socket if its behind them. Having seen a tumble drier burst into flames in the past, I would not fancy having to pull it out of a 605mm wide hole in a hurry in order to isolate it. Adjacent cupboard is ok, as long as its not so full of stuff you can't get to the socket.

[ARWadsworth]

That can easily be achieved. The socket can be at the front of the cupboard.

And I will not use a tumble dryer at night for that reason.

[John Rumm]

Yup, did it that way myself at my last place... although technically you are not supposed to mount fixed electrical accessories on "furniture"...

Probably wise...

[js.b1]

Tumble dryers are very crude devices, with crude safety features.

The biggest problem seems to be lint buildup.

Some dryers have small high temperature heating elements. Basically nichrome wire on a heating resisting card former, little different to a toaster, 3kW in a space little more than a large baked bean tin. I was expecting PTC or mineral sheathed elements like an oven or washing machine. Whilst dryers are not on for long, air drawn in will cause significant buildup of microscopic particles of lint - which actually have a surprisingly low ignition temperature.

Do dryers recirculate air over the heater element repeatedly through the internal filters? Whilst most dryers have a large door filter, and a secondary filter, they are poor at retaining microscopic lint particles. When people open a dryer they drag their fingernails over the secondary filter, serving to push the microscopic particles through it. If that air (and particles) are recirculated then it will contribute to lint buildup elsewhere.

Safety devices are "after the fact" in terms of sensing overheating, and "not necessarily in the right place" in terms of lint may be at ignition temperature elsewhere. They could do with an optical smoke alarm building in, plus a "belt has snapped" hall effect sensor, motor is stalled, exhaust is clogged, filter is clogged. Interlink the smoke alarm to the power and sounder.

I do run a dryer overnight, but have two mains interlinked smoke alarms in that room (optical & ionisation side by side) because it is near the kitchen. I think someone does actually make a smoke alarm with relay box for appliances. They are such noisy appliances even through a closed door (which for people without a working smoke alarm could be deadly). They should come with a separate smoke alarm, perhaps an extra loud unit, and ideally one built in. Optical should work fine - forcing people to clean the filter and its lens. A refusal to start if the filter is not cleaned by weighing it (strain gauge).

Hilariously primitive devices with rather large price tags.

Then again, cheap AC extractors often lack thermal fuses or even bimetallic trips, hence have become an increasing source of fires - never mind the old cooker hood duct full of grease. I loved how DC fans can suffer PSU failures, that really takes the biscuit.