Advance Combi Boiler

Forry1759 · Jun 12, 2023

The new Advance Combi Boiler has a feed from consumer unit using 6mm cable on a 32amp breaker to a 45amp double pole switch. What size cable to the boiler should it be from this switch. It has a fused 3amp supply to the electronics section.

DefyG · Jun 13, 2023

4 or 6 6sq mm flexible, heat resisting.

bennie · Jun 13, 2023

Are you putting a SFCU with a three amp fuse for the boiler controls and a 20 amp switch for the immersion??

Forry1759 · Jun 13, 2023

bennie said:
Are you putting a SFCU with a three amp fuse for the boiler controls and a 20 amp switch for the immersion??

Yes, Bennie but a 32amp circuit breaker on 6mm

bennie · Jun 13, 2023

Forry1759 said:
Yes, Bennie but a 32amp circuit breaker on 6mm

Ok, that's fine

davesparks · Jun 13, 2023

The flex should ideally be the same size as the supply cable, so 6mm.

Plus make sure you use ferrules where required, just a few broken strands on a load like this can be enough to cause a failure.

bennie · Jun 13, 2023

Change the size of the breaker as you don't need 32 amps and use a smaller cable.

davesparks · Jun 13, 2023

bennie said:
Change the size of the breaker as you don't need 32 amps and use a smaller cable.

What size MCB would you fit as 32A is the nearest size MCB available to what is required?

bennie · Jun 13, 2023

Whoops, just red the attachments again

Forry1759 · Jun 13, 2023

davesparks said:
The flex should ideally be the same size as the supply cable, so 6mm.

Plus make sure you use ferrules where required, just a few broken strands on a load like this can be enough to cause a failure.

Thank you Davesparks, very useful information