Combi boiler

[george81]

Hi all,I have a question about wiring for combi boiler in my kitchen. At present there is a flex coming from boiler to a connection point. From there runs another flex with plug which plugs into socket and another cable running to timer. Could I just make the connection point a switched FCU to save having to plug it into socket and also connect the cable running to timer? Also would I make this a 3A FCU?Thanks for your help in advance

 

[1shortcircuit]

Hi George, any chance you could post up a picture please? :thumbsup

 

[Geoffsd]

Yes a switched 3A FCU is ideal.

Not sure what you meant about the cabling.
Normally boilers are wired by having all the cables - from supply, boiler, timer, stats, valves, - running to a central wiring box.

 

[george81]

Thanks for your replies guys. Sorry I haven't got a photo at moment as it's my sister in laws. She had it installed a month or two ago and I was surprised when I saw she had it plugged into her double socket in her kitchen. Seemed a waste of a socket. Just to confirm then that I could run the flex from the boiler into the switched FCU and also run from same FCU to timer. Would it be double pole switch?

 

[Geoffsd]

Just to confirm then that I could run the flex from the boiler into the switched FCU

Yes, you can use the SFCU to supply the boiler,

and also run from same FCU to timer.

Not really, because the timer would have to interrupt the supply to part of the boiler system but the boiler needs a permanent supply available at the same time.
You would have to connect the boiler to the FCU and connect the timer to the appropriate terminals in the boiler or have a central wiring box.

Would it be double pole switch?

Yes.

Do you have any thermostats and/or motorised valves in the pipework?

 

[1shortcircuit]

Mine has one flex coming from the FCU flex outlet that goes to the programmer. Two flex come out of this and then go into the boiler:thumbsup

 

[Geoffsd]

I'm a bit confused.

Is the boiler working already? If so then just swap the plug for an FCU.

If not what are you trying to do?

 

[1shortcircuit]

I'm a bit confused.

Is the boiler working already? If so then just swap the plug for an FCU.

If not what are you trying to do?

This is why I suggested a photo

 

[Geoffsd]

This is why I suggested a photo

Yes, funny how very simple questions end up mystifying.:confused5:

 

[george81]

Sorry for my vague description. Am describing it from memory. Yes system is working fine it just seemed weird to have it plugged in. Is this common? Was just hoping to simplify it a bit

 

[1shortcircuit]

Sorry for my vague description. Am describing it from memory. Yes system is working fine it just seemed weird to have it plugged in. Is this common? Was just hoping to simplify it a bit

I believe this is a common method of providing means of Isolation. As daft as it may seem, it does exactly what it's supposed to



:thumbsup

 

[Geordie Spark]

Some combi boiler manufacturers supply their boilers with a cable & plug top attached.

I usually use a bit of 5 or 6 core from boiler to 3 Amp DP FCU where I connect 3 of the cores for L, N & E and the remaining 2 (or 3) cores are connected to the control lines which I bring from the controller (room stat, timer etc.) into the patress / back box for the FCU using crimps or Wagos.

This way, only one cable is showing hanging out of the boiler.