Wiring a bathroom heater.

[craigban]

Hi, i have just purchased a bathroom wall heater which needs to be hard wired with the mains electricity via a 13A spur.

I already have a live switch on the wall outside the bathroom which is wired directly from the 30A fuse in the fuse box which was originally used to supply a shower when i first moved into the property, i no longer have the shower or anything else wired to it so basically it is just a heavy gauge cable running from the 30A fuse in the fuse box to a switch on the wall with nothing between.

Firstly, would this circuit be ok to run my 1.8kw heater from?

Secondly, if so can i just remove the switch which is already there (after i have made sure the electricity is turned off and the circuit is isolated) and replace it with a 13A fused switch from which i can then run another cable to the heater?

Any advise would be greatly appreciated,

Thanks.

 

[Chri5]

What you intend to do is fine, a fused spur to replace the shower switch and extend on to the heater.

Devices in bathrooms are subject to zones and IP rating (see Wiki at top of page / uk electrics / bathroom zones).

If the circuit isn't rcd protected at the CU then opt for a fused spur with in built RCD.

1800w is about 7.5 amp so the fused spur needs a 10 amp fuse.

 

[craigban]

What you intend to do is fine, a fused spur to replace the shower switch and extend on to the heater.

Devices in bathrooms are subject to zones and IP rating (see Wiki at top of page / uk electrics / bathroom zones).

If the circuit isn't rcd protected at the CU then opt for a fused spur with in built RCD.

1800w is about 7.5 amp so the fused spur needs a 10 amp fuse.

Hi chri5, thanks for your quick reply.

Sorry i forgot to mention the circuit is RCD protected and that the heater is to be fitted above head height on the opposite wall to the bath which is about 8 feet away.

Could you please tell me if the positioning of the heater seems ok and what size cable i will need from the fused switch to the heater - i was going to use either 1.0 mm2 or 1.25 mm2

Thanks again.

 

[Chri5]

Sounds fine.

You should check against the zone diagrams in the wiki. You are the only one who will be able to confirm the position is acceptable.

Also note my sig- Part P applies to bathroom electrics............

 

[Taylortwocities]

Could you please tell me if the positioning of the heater seems ok and what size cable i will need from the fused switch to the heater - i was going to use either 1.0 mm2 or 1.25 mm2

Thanks again.

Surely the appliance must come with a suitable flex already attached.?

 

[craigban]

Sounds fine.

You should check against the zone diagrams in the wiki. You are the only one who will be able to confirm the position is acceptable.

Also note my sig- Part P applies to bathroom electrics............

Hi again chri5,

I have just checked the zone diagrams as you suggested and would say that the positioning of the heater would fall into the 'outside of zones' category as it is at least 6 feet away from any water supply.

Thanks again for all your help,

Craig.

 

[craigban]

Could you please tell me if the positioning of the heater seems ok and what size cable i will need from the fused switch to the heater - i was going to use either 1.0 mm2 or 1.25 mm2

Thanks again.

Surely the appliance must come with a suitable flex already attached.?

Hi Taylortwocities,

No there is no cable attached to the heater, you have to remove a cover on the front of the unit and connect one to a chocbloc.

I think they probably leave the cable off so that people dont just stick a plug on and use it from a socket.

I want to run the cable through the roof space and chase it down the bathroom wall so would probably have had to buy new anyway.

 

[Adam_151]

Standard practice would be to fit a flex outlet place near the heater, run from there to the fused spur in 2.5mm twin and earth (you *could* get away with smaller, but its just not the 'done thing'), and then flex the heater up with 1.5mm heat resistant flex, 13A fuse in spur

Make sure this circuit is included in the sup bonding and note that the work you intend to dois notifiable

 

[craigban]

Standard practice would be to fit a flex outlet place near the heater, run from there to the fused spur in 2.5mm twin and earth (you *could* get away with smaller, but its just not the 'done thing'), and then flex the heater up with 1.5mm heat resistant flex, 13A fuse in spur

Make sure this circuit is included in the sup bonding and note that the work you intend to dois notifiable

Hi Adam_151,

By a flex outlet am i right in thinking you mean a junction box?

 

[Adam_151]

No, a flex outlet plate: http://www.screwfix.com/prods/70006...lded/MK-Range/MK-20A-1-Gang-Flex-Outlet-White

Fits on a standard single gang box and provides terminals to join the flex to the fixed wiring and a cord grip

 

[craigban]

No, a flex outlet plate: http://www.screwfix.com/prods/70006...lded/MK-Range/MK-20A-1-Gang-Flex-Outlet-White

Fits on a standard single gang box and provides terminals to join the flex to the fixed wiring and a cord grip

Ah right got that,

Thanks a lot.

 

[kai]

It is advised that the 30amp fuse in the consumer unit is replaced by a B15/B16amp breaker, or even a B10 breaker is possible, to match the power requirement of the new heater.

 

[Steve]

Sorry i forgot to mention the circuit is RCD protected and that the heater is to be fitted above head height on the opposite wall to the bath which is about 8 feet away.

Just for my own curiosity, can you explain how? I only ask because "30A fuse" indicates an aged installation with no RCD protection. Is ther a seperate RCD?

 

[craigban]

Sorry i forgot to mention the circuit is RCD protected and that the heater is to be fitted above head height on the opposite wall to the bath which is about 8 feet away.

Just for my own curiosity, can you explain how? I only ask because "30A fuse" indicates an aged installation with no RCD protection. Is ther a seperate RCD?

Hi Steve,

No it is built into the fusebox, it definitely trips on every circuit as i have just had a new heating system fitted and the lad that fitted it tested the RCD as well as fitting an earth rod outside.

 

[Steve]

Can you post a picture of the fuse box and the surrounding area? This is sounding odder by the minute.

Why did he fit an earth rod? Did you not have a main earth before?