Is this ok?

[dantheram]

I have a power socket which currently supplies a washing machine (2300w). The socket appears to be the end of a radial circuit.

I wish to add underfloor heating (750w) to this socket. I am considering adding a 13a FCU before the socket supplying the washer then running on to the underfloor heating. Total possible draw will be 3050w on 13a socket.

 

[JohnW2]

I have a power socket which currently supplies a washing machine (2300w). The socket appears to be the end of a radial circuit.

At this stage, questions rather than answers! .... How sure are you that it's at the end of a radial circuit, and are there any other sockets on that circuit? What size fuse or MCB is protecting the circuit - and do you know what size cable it uses?

Kind Regards, John

 

[wingcoax]

You really need to make sure that it IS a radial circuit and not a spur off a ring final circuit.

 

[dantheram]

You really need to make sure that it IS a radial circuit and not a spur off a ring final circuit.

Definitely not a ring, has a supply but does not have anything going back round to the mcb.

 

[dantheram]

I have a power socket which currently supplies a washing machine (2300w). The socket appears to be the end of a radial circuit.

At this stage, questions rather than answers! .... How sure are you that it's at the end of a radial circuit, and are there any other sockets on that circuit? What size fuse or MCB is protecting the circuit - and do you know what size cable it uses?

Kind Regards, John

2.5mm. Mcb 30a. I can't see where the cable comes from but it appears to come up out of the floor, it's on the same breaker as all power sockets in the house, except the cooker. How can I tell if it's a radial?

 

[Iggifer]

pop the cover off the closest socket and I'm pretty sure you will find 3 cables - likely indicating your current socket is a spur from a ring and not a branch from a radial

The only real way to know for sure is to test/look inside the consumer unit and see how many cables are coming out of the fuseholder.

As you say 30a I assume you have a fuseboard and not a consumer unit and therefore no RCD, which you will likely need for your UFH

 

[JohnW2]

2.5mm. Mcb 30a. I can't see where the cable comes from but it appears to come up out of the floor, it's on the same breaker as all power sockets in the house, except the cooker. How can I tell if it's a radial?

The fact that the socket in question does not have a second cable does not mean that it has to be a radial - as has been said, it could be a spur off a ring, in which case you could not do as you have proposed. That's one reason why it's important to find out what sort of circuit it is.

If it really is 2.5mm² cable then, unless it's all been done wrong (and unsafely) it cannot be the main part of a radial if it is protected by a 30/32A MCB.

Are you sure that it's a 30A MCB - 32A would be far more common (or is it perhaps a 30A fuse?)? Have you seen inside the CU? If the circuit is a ring, there will be at least two (red or brown) wires going into the MCB. If there is only one wire, then it must be a radial.

Kind Regards, John

 

[securespark]

There are 30A Type 1 and Type 2 MCB's around.

 

[dantheram]

I have a Residule current operated circuit breaker. The power sockets are protected by a 30a fuse. The nearest socket does indeed have 3 cables so I'm thinking this is a spur of that socket.

 

[JohnW2]

There are 30A Type 1 and Type 2 MCB's around.

I know there are - but for every one of those that are 'around', you'd find countless thousands, if not millions, of B32s! That's why I said that, for an MCB, 32A would be "far more common" (not 'inevitable')

Kind Regards, John

 

[dantheram]

There are 30A Type 1 and Type 2 MCB's around.

I know there are - but for every one of those that are 'around', you'd find countless thousands, if not millions, of B32s! That's why I said that, for an MCB, 32A would be "far more common" (not 'inevitable')

Kind Regards, John

Mine says type 2 under all the switches.

 

[JohnW2]

I have a Residule current operated circuit breaker. The power sockets are protected by a 30a fuse. The nearest socket does indeed have 3 cables so I'm thinking this is a spur of that socket.

That's what we feared. In that case, as I said, you cannot do as you proposed. One possibility ... is there another socket nearby which has only two cables, from which you could take another spur for a 13A FCU?

However, another issue is that if, as you've said, this is the only sockets circuit in the house, you should probably consider whether it is really appropriate to run the UFH off it, rather than from a new circuit of its own.

Kind Regards, John

 

[JohnW2]

Mine says type 2 under all the switches.

Now I'm getting confused You just said that it was a 30A fuse. Is it a fuse, or a 30A Type 2 MCB?

Kind Regards, John

 

[dantheram]

On the box itself it's called a residual current operated circuit breaker. The power point switch at the same box is noted at 30a type 2.

 

[JohnW2]

On the box itself it's called a residual current operated circuit breaker. The power point switch at the same box is noted at 30a type 2.

Any chance of a photo of this? ("we like photos"!)

Kind Regards, John