Supply to heating system

[Jever]

Hi all,

I'm doing a refurb on a bungalow and have taken out the old electric powered heating system with the intention of installing an oil or LPG fuelled system.

This means I will need to provide a source of electricity to the new boiler. From what I've seen, this usually means taking a cable from the consumer unit (separate fuse for the supply) to a fused connector unit (so that it can be isolated) and then from the fcu to the boiler (be it oil or LPG) itself.

Is this correct? If so, what cable would it be best to use? I can't imagine anything more than 1.5mm t&e being needed but I thought it best to as the experts.

TIA

Jever

 

[EFLImpudence]

This means I will need to provide a source of electricity to the new boiler. From what I've seen, this usually means taking a cable from the consumer unit (separate fuse for the supply) to a fused connector unit (so that it can be isolated) and then from the fcu to the boiler (be it oil or LPG) itself.

Is this correct?

No. That is most unusual but might be beneficial.
The supply can be taken from any circuit - sockets, lights, immersion.

The only proviso is that all of the heating system must be from the same FCU.

If so, what cable would it be best to use? I can't imagine anything more than 1.5mm t&e being needed but I thought it best to as the experts.

The fuse in the FCU will be 3A so virtually any cable would do.
Use 1mm² t&e, it will be more than adequate. 1.5mm² obviously is also fine.

 

[Jever]

Great, thanks.

 

[AndyPRK]

Yes if you have a spare slot in the CU and it is close by, a direct feed is good with 6A MCB (incase the other circuit develops a fault in the middle of winter).

However normally it is just spured off the socket circuit.

 

[Jever]

Hi,

That's helpful, thanks.

Now I think about it, the system that I got the idea from was supplying the (back up) immersion heater as well as the boiler, which makes sense to me.

I won't have an immersion at the bungalow I'm working on but it still seems a good idea to keep the heating system separate. That way, if an appliance on the socket ring main causes the fuse to cut the circuit, the heating system continues uninterupted.

Regards

Jever

 

[Harry Bloomfield]

Now I think about it, the system that I got the idea from was supplying the (back up) immersion heater as well as the boiler, which makes sense to me.

Not an especially good idea. If the boiler/heating system develops a fault, it may need to be isolated. Loosing both the boiler's ability to heat water and your backup immersion heater, will makes things somewhat awkward.