Is an RCD required?

[ADringer]

I'm planning on getting some underfloor heating, specifically WarmUp ( http://www.warmup.co.uk/uk/loose-wire-underfloor-heating-system.phtml)

This will be spured off an existing socket. The installation document says 'The electrician must install a dedicated RCD or use an existing RCD'. My consumer unit is RCD protected, will it be enough to use this RCD and use a fused spur or will I need a seperate RCD?

Thanks for your help.

 

[Taylortwocities]

You do not need another RCD if the RCD in your consumer unit protects the circuit that the underfloor heating will be powered from.

Trip the RCD by pressing the test button and see if power is interrupted to that socket.

 

[ADringer]

Great, that's what I was hoping! We're just doing up a house and my wife has gone for all black nickel switches and sockets, but the only RCDs I've seen are quite ugly. Wasn't sure how that would go down if I had to put one in!

 

[PrenticeBoyofDerry]

The manufacturers instructions must be folled.
If your installation already has RCD protection at the board, firstly make sure that the circuit powering the UFH, is from one that is being protected at the board. Don't accept it as gimme! Also have tested to ensure that it is working.

 

[ADringer]

The manufacturers instructions must be folled.
If your installation already has RCD protection at the board, firstly make sure that the circuit powering the UFH, is from one that is being protected at the board. Don't accept it as gimme! Also have tested to ensure that it is working.

I assume that is a case of pressing the 'test' button and check that power is cut to the socket I'm spurring from?

 

[Taylortwocities]

The test button is a very basic mechanical test. Your electrician must test the RCD's operating times with an RCD tester to make sure they meet the standards that will save your life if there is a fault.
The operating times will go on the Minor Works Certiificate that he will give you. He will also know that this is notifiable work.

You know the hazards:- coils of energised electrical wire only a few millimetres from your wet feet and body...........

 

[ban-all-sheds]

I'm planning on getting some underfloor heating, specifically WarmUp ( http://www.warmup.co.uk/uk/loose-wire-underfloor-heating-system.phtml)

OOI, why?

What do you think it will do for you?

 

[ADringer]

I'm planning on getting some underfloor heating, specifically WarmUp ( http://www.warmup.co.uk/uk/loose-wire-underfloor-heating-system.phtml)

OOI, why?

What do you think it will do for you?

Do you mean underfloor heating generally, or WarmUp specifically?

I'm using in conjunction with a radiator, not as a primary source of heat. It's just to take the edge of the tiles when it's cold.

 

[ban-all-sheds]

So given the issues of climate change and the approaching shortfall in our generating capacity, do you believe that that's a socially responsible thing to do, rather than wear something on your feet?

 

[ADringer]

So given the issues of climate change and the approaching shortfall in our generating capacity, do you believe that that's a socially responsible thing to do, rather than wear something on your feet?

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[DaftPunk]

I'm certain he will be, but just ignore him like everyone else does.

 

[ericmark]

I am very surprised not already mentioned but there are many flavours of RCD and what you will need is a 30mA version it states:-

415.1.1 The use of RCDs with a rated residual operating current (I∆n) not exceeding 30 mA and an operating time not exceeding 40 ms at a residual current of 5 I∆n is recognised in a.c. systems as additional protection in the event of failure of the provision for basic protection and/or the provision for fault protection or carelessness by users.

Before 2008 it was common with TT earth systems to use 100 mA S type RCD's on domestic supplies these will clearly help but are not fast enough or sensitive enough to protect people. So you must look for 30 mA written on the RCD.

Would be interesting to hear a report on how you find the underfloor heating. I was very disappointed when fitted in mothers wet room the warm up time was far too slow and once cooled with water the re-heat time was too slow. As for keeping the room warm any hotter you could not walk on the floor yet without the towel rail the room is cold.

My son has fitted under floor heating in bedrooms but as yet not used. His is water with pipes under floor this clearly does not have the hot spot problems associated with electric type. With a wet room nothing is left around on the floor so no problem with hot spots but something as simple as placing shopping on the floor with other rooms can clearly be a problem.

It states "double-insulated" and also states "Dual core earth screened cable" which seems to point to not being double insulated! There are two types of electric underfloor heating. The is a chemical type where as the cable warms up the resistance increases also used with trace heating on pipes and this means it can be cut to length and also is less likely to over heat if covered with something. The other is a basic resistance wire often whole length must be laid some times it is a load of parallel heating elements which can be cut but these can over heat very easy if covered.

The type you link to has clear instructions must be laid under quarry or ceramic tiles these will tend to conduct the heat away from hot spots all the instructions seem to show it being used in a bathroom which is unlikely to have any furniture in covering the floor. I would not use this type in any other type of room.

 

[winston1]

Although they suggest you don't need to raise the floor etc, I can tell you from experience that if you just lay it and tile over as suggested you will lose a substantial portion of the heat downwards and it will take forever to heat up.
You need a layer of insulation under the heating wire.

 

[PrenticeBoyofDerry]

I assume that is a case of pressing the 'test' button and check that power is cut to the socket I'm spurring from?

No, all that does is prove the mechanism is working and not seized or stuck.
The tripping times at 30mA will be required, there are number of these test at 1/2, full and x5 of that rating, using both positive and negative cycles.

 

[plugwash]

So given the issues of climate change and the approaching shortfall in our generating capacity, do you believe that that's a socially responsible thing to do, rather than wear something on your feet?

I don't see how it's any more socially irresponsible than jetting off arround the world on holiday or having a big house or flying light aircraft for fun or many of the other things people choose to spend their resources on. Ultimately virtually every luxury we indulge in demands the use of energy.