UK Spur off a 4mm twin and earth, 32amp radial

[JLH520]

I have a dedicated radial from the consumer unit to my conservatory. This was installed using 4mm twin and earth as it gives the option to use multiple electric heaters on a 32amp breaker if needed. The circuit consists 4 double sockets plus one single socket on the end, in a weatherproofed box on the wall outside. As it happens, I rarely need to use electric heaters in there, as there are plumbed radiators too, so the radial is easily over specced and currently has only a 16amp breaker.

Now I need to add two extra double sockets outside to power two 2500 watt infra red heaters under a gazebo (each has a 13 amp 3 pin UK plug fitted, they won’t be hardwired). I am hoping to be able to add these sockets by running a spur from the conservatory radial circuit as it could comfortably cope with the draw from the heaters. My intention was to continue a 4mm twin and earth spur to these additional two sockets outside so that the whole radial is safely capable of handling 32 amps.

The problem is that a fused connection unit which handles a fuse above 13 amp doesn’t seem to exist, so I’m wondering how best to safely connect this spur to my radial circuit and isolate the outside circuits if need be?

Any helpful suggestions on how to implement this would be greatly appreciated

 

[JLH520]

How is the new cable going to be installed.

…was planning to run 4mm SWA to the new sockets. Had planned to use a short run (approx 1 metre) of 4mm twin and earth in a conduit between the two sockets rather than use SWA between the two sockets. Is 4mm T&E permissible in conduit over this short distance?

 

[westward10]

…was planning to run 4mm SWA to the new sockets. Had planned to use a short run (approx 1 metre) of 4mm twin and earth in a conduit between the two sockets rather than use SWA between the two sockets. Is 4mm T&E permissible in conduit over this short distance?

Contained in conduit it would not be rated at 32A unless it is singles.

 

[JLH520]

Contained in conduit it would not be rated at 32A unless it is singles.

Ok understood, thanks.

 

[brianmoooore]

If the bit in the conduit only feeds one socket, then it doesn't need overload protection - just short circuit protection.

 

[JLH520]

If the bit in the conduit only feeds one socket, then it doesn't need overload protection - just short circuit protection.

Ok, thanks Brian, that helps.

 

[MDJ]

never agreed with thatpete. it may have been relevant when a house had only 1 RFC (ncluding kitchen) but these days it's rare to see a non-kitchen RFC loaded to >5A or 6A. we had a 2.2kW hot tub , 2.2kW sauna, 3 freezers, washer, fumble dryer, all on a 16A radial (garage). cable used to get slightly warm. made ito a RFC (when sauna was added) to a 32A RFC just to be safe.

Firstly why is a guy who is 80 still working? secondly Tel nice to see you are still alive ?

 

[Dave OCD]

I'm not being funny here but why would anyone in their right mind want to use a considerable amount of electricity to warm outside ? The world is in a bad enough state already ?? No offence intended.

 

[DPG]

I'm not being funny here but why would anyone in their right mind want to use a considerable amount of electricity to warm outside ? The world is in a bad enough state already ?? No offence intended.

Indeed. 5 kilowatts of electricity to heat the outdoors!

 

[brianmoooore]

My tumble drier is 5kW, and it doesn't half make the red light on the meter flash! All that heat goes outdoors as well.

 

[Dave OCD]

What are you drying Brian, a marquee ? ?

 

[nicebutdim]

My tumble drier is 5kW, and it doesn't half make the red light on the meter flash! All that heat goes outdoors as well.

At least you get dry clothes through the process of filtering air to heat outdoors.

 

[brianmoooore]

Laundry from holiday cottages. American sized washing machine and tumble drier.

 

[telectrix]

Laundry from holiday cottages. American sized washing machine and tumble drier.

even though, eack kWH will dry to a set level. 5kW will just be quicker then a 3 kW unit. energy in = energy out, and all that.

 

[telectrix]

Firstly why is a guy who is 80 still working? secondly Tel nice to see you are still alive ?

am only taking on small, non-mauling jobs now. legs are knackered and lungs are dicey. be 75 in a week. another few years before son needs to find somewhere for my tools. he's already scrounged the 1553 i bought off you 7 years ago. crikey, time flies when you're a coffin dodger.

 

[littlespark]

75?

You’ll be looking forward to a life of diddy little diy jobs, watching YouTube videos of tractors, engines and other machinery just moving…. Not actually doing anything and drinking copious amounts of coffee…

That’s what my 75 year old dad does