Another Whirlpool bath question.

5 Nov 2005
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United Kingdom

Just finished sorting out the wiring in our new flat but one problem left. Our new whirlpool bath.

The consumer unit we have is an old stlye one with the plug in fuses. it has four fuses. A 5amp for lighting, 15amp for ring main, 15amp for immersion heater and 30amp for the cooker.

From what i have read on here i can connect the bath to a spur off the ring main using a rcd protected switched fused connection unit. Does this mean i can run a spur from the ring main, stick a switched fused connection unit on it, and then fit a passive inline rcd plug to the cable that comes off the whirlpool bath? the cable is long enough to go out of the bathroom and into the room that houses the consumer unit.

Is this an ok thing to do or am i going to die?

Is there something better on the market to do this task? is so any uk links? none of the big diy stores around here seem to have much choice when it comes to this sort of thing.

The whirlpool bath is 0.7kw 230v and 2.5amps.

Any help will be greatly appreciated as i am looking forward to my first bubble bath' :D

What size cable should i use for the spur? should 2.5mm2 be ok since the unit doesn't seem to require much power.

thanks in advance.

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Use an RCD protected fused connection unit outside the bathroom. This job is part p.

If you have just fiished the wiring in the flat, then
1. why still have old consumer unit
2. why 15amp ring main?
Where can i get one of those from? i have looked in the likes of B&Q, Wickes, Homebase etc but none of them seem to stock anything like this. Do you have any links to a uk site so I can at least see what i am looking for?

EDIT: Have just looked around a bit and this this suitable for the job . is that a good make and about the right price?

I havn't done a complete re-wire of the flat or anything like that, just extended the ring main so i could have some plug sockets in the bedroom.

All the electrics in the flat seem to work fine so i was basically thinking if it ain't broke then don't fix it. Unless there is a compelling reason to change the CU for a new modern one?

From looking around on this site I realise that local authorities will need to be notified before i can do anything, but at the moment i'm just tring to find out what equipment i need to do the job.

Thanks in advance.



With regards to the 15amp ring main, this is just what is already there. the flat is quite old (victorian times) and I guess back then they didn't use much electricity. The cable is all 2C+E and is 2.5mm2. The CU is color coded (White 5amp, Blue 15amp and red, 30amp).

It is only a one bedroom flat so the chances of overloading the circuit i guess are pretty slim as there is not going to be very much turned on at the same time. just a projector and a couple of pc's and a fish tank.

If this layout ok to use? Could i just put a bigger fuse in since the cabling is the correct size? at the moment I don't want to have to do any major electrical work as we are still in the process of doing the whole place up so we can move in. Later down the line I will require electrics in the garden for a fish pond and lighting but I will get an electrician in to do that sort of stuff. At the moment I just want to get the basics working.


please see forum rules 10a
You should get it all inspected.

You say it's 2.5mm², but are you sure? Is it solid or stranded? What size is the earth conductor? Is it PVC insulated?

And at 15A, it might well not be a ring circuit, BTW.

How much of the wiring did you expose? It's not unknown for some cowboy to replace the bits you see when looking at sockets and fuseboxes etc, and leave most of the old stuff behind.

Your fusebox has the hallmarks of an old installation, with all the possibilities that entails in terms of old and dangerous cables, inadequately sized cables, inadequate main and supplementary bonding, no earth on the lighting circuit etc etc.

You'll not be too happy if in a few months/years time, after you've got furniture, carpets, done a bit of decoration etc, you find that all the wiring has to be ripped out.

I'm not saying that it does, but now is the time to find out, because if it is necessary now is the time to do it.
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It is definately 2.5mm2 cable and it is solid core. Not sure what size the earth conuctor is off the top of my head as I am not at the property at the moment but it is exactly the same size as the new cable I have just been given which I have been told is the correct cable for ring mains.

Don't know what it is insulated with, it feels like PVC as opposed to rubber.

It is definately a ring circuit. I disconnected all of the plugs and the wires from the CU and used a test meter to trace where each wire goes from and too and it is a complete ring with two spurs coming from it.

Nearly all of the actual wiring is exposed in this place. only time it goes out of site is when it goes through a hole in the wall and out the other side. The wires are run around the outside of the walls. It looks as if when the place was originally built it prob didn't have electricity and this was added at a later date. (It used to be the servents quarters and housed the bread oven)

All of the wiring for the ring main is 2.5mm2 cable and looks to be undamaged so this should be ok?

The lighting circuit does have an earth on it and all looks to be intact with no bodge jobs as far as i can see.

I got a couple of people I know who are electricians but I want to try and get everything sorted and where I want it and then get it all checked out in one go when it comes to the big turn on date.

Do you know if the RCD SFCU from the link above will do the job ok for the whirlpool bath?

thanks in advance.

cant get onto the link above, search error or something, but this is what you need:
switch fused connection unit (click)
Ban is right, it should be inspected, it is an old installation, and what looks ok to a DIYer may in fact be quite dangerous.

You mention having garden electrics installed: if this is the case, it would pay to upgrade the consumer unit now, for one with RCD protection. outdoor electrics need RCD protection. Also, you wouldn't need the RCD SFCU above if there is an RCD in the main consumer unit.
Ok guys. thanks for the help and advice.

I'll see about getting someone in and getting the CU replaced. What sort of price do you think I would pay to get the new unit connected up (Will prob buy and fit it in place myself and then get electrician to do the wiring side of things).

Obviously this depends on if he finds anything else but if the job goes straight forward any rough estimates?

Thanks in advance.

shhh not allowed to ask for prices, but set aside £300-400 for him to fit and test it. if you are buying it, discuss this with your chosen electrician before, as some like one particular brand more, and he will be able to tell you which to buy. But it may be best to let him buy it, he can get wholesale discounts, you cant.
Thanks for the help. Guess my robotic vacuum cleaner will have to wait a few more months then :)

Cheers, Matt.

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