Room Heaters

[ryanj]

I have recently bought two large electric room heaters, there total current works out at 18.2amps, should I:-

a) power them from the ring circuit via a FCU
b) create a 20amp radial circuit for them
c) or, give each of them a seperate 10amp radial circuit

If I choose option b or c, should I protect them via a RCBO or will a MCB suffice?

Thanks, in advance!

 

[plugwash]

either B or C is fine A is probablly not a very good idea

if you use the 20A radial then you must connect the heaters using fcus

there no need for RCD or RCBO protection on such a cuircuit

 

[ryanj]

Thank you for your quick reply...

Now I need to decide between B+C, is there really any benifet from having them on different circuits?

 

[ZenStalinist]

The problem with A is that they could overload the ring. If you add another ring in for them it should be fine (let's call it option D).

I wouldn't see any advantage in C, I'd personally go for B. It seems the best option anyways.

They don't have to be on the RCD side or protected by an RCBO, an MCB will suffice, but you may still prefer to use RCBO/RCD.

I don't know if they should be FCU protected on option B... I've never done a heating circuit before. But then wouldn't that be restricted to a floor area of 20 sq metres?

You could always go for option D, put a separate ring circuit (32 amps) in for them, with FCUs. Then you have ability to expand the system further.

 

[ryanj]

20 sq metres? Wouldn't it be 50sq metres?

 

[securespark]

But not much further, with each heater approx 10A.

 

[plugwash]

i thought the 50 square meters was just a guideline for domestic socket cuircuits

this is not a socket cuircuit its a full rated cuircuit for two fixed appliances

 

[David E]

Following on from the original post can I please ask a couple more questions?

1. Does each storage heater need it's own radial circuit with individual FCU's or is the dedicated 2.5mm ring option better with a NEW installation

2. If the mutiple radial circuit option is chosen are there any MCB's with timers incorperated that only take up one MCB slot in the CU and if so are they suitable for switching storage heaters on/off? (if the ring option is chosen I will have 3 spaces to use / if radial each of the 3 heaters will need their own slot and MCB/timer)

 

[breezer]

storage heaters are usually on their own consumers unit, which is only live at night, so as to use "cheaper" night time electricity

 

[David E]

Basically the supply to the house is from the our farm supply(decent 20mm^2 SWA cable laid properly) so Economy 7 is not really feasable. Space for another CU is a bit of an issue to supply just the storage heaters thus the idea of the combind MCB/timer. Any other ideas? Maybe timers in the storage heaters?

David

 

[plugwash]

immersion heater timers should be suitable
click me
they should be fitted next to the heaters after all fuses/breakers

 

[David E]

Thanks plugwash for the suggestion, the only problem would be children fiddling with the timers so a "hidden" one would be better. Any more ideas anyone?

thanks

David

 

[breezer]

its not ideal, but put the timers next to the consumers unit, then a cable from each to the heater

 

[plugwash]

yeah if you go that way you must use have them breakered or fused at 10A (well 13A or less but since your heaters are under 10A before the timers)

 

[ban-all-sheds]

Don't suppose there's room in your CU for something like this, is there?

Alternatively, 2-birds-with-one-stone approach - do you think the kids would mess with something like this?