Replacing switch for boiler

[ray.birch]

Good afternoon all,

(The Introduction bit - not necessarily important!!)
I have a Vaillant ecoTec Pro 24 boiler that had been recently installed when we bought our current home almost 2 years ago. The wiring had also been done fairly recently, but as we have found out, the quality of some of the components used has been pretty low in places.

As an example, the sockets used in the kitchen are a British General flush screwless model, for which most of the faceplates have lost their clips, and fall off the wall when the appliances are unplugged.

As we are redecorating, I am going through and swapping all of these out with Stainless Steel flush (but visible screw) sockets. These ones in fact: http://www.screwfix.com/p/lap-13a-2...ocket-brushed-stainless-steel-pack-of-5/68831


The main question!
As part of renewing these sockets, I have come across one which looks like a 45A cooker switch (are there others which have the red switch that I could be getting confused with?). Interestingly, this is not isolating power to the cooker, but to the boiler. Having looked at the Vaillant ecoTec Pro 24 installation manual, it recommends a 3A fused electrical connection. As far as I am aware, this existing setup is not adhering to this?
Manuals that I have found are here: https://www.vaillant.co.uk/downloads/ecotec-pro-instn-maint-261423.pdf
and here: https://www.vaillant.co.uk/download...manuals-1/ecotec-pro-0020209589-00-525250.pdf



My following question is whether I can legitimately replace the offending switch with this: http://www.screwfix.com/p/lap-13a-switched-fused-connection-unit-brushed-stainless-steel/31552 and then replace the fuse with a 3A variant? Is this work notifiable (or would it come under maintenance (given I am replacing all switches and not chasing/removing any circuits).

One last thing to note is that the boiler switch is not on the RCD protected circuits. From what I have read, I don't believe this in itself is a problem, but it would be great to confirm from someone more in the know! Having had very little time at home this week, I've yet to check which MCB the boiler is actually on, but I expect that the 3A manufacturer recommendation is being exceeded nonetheless!!

Many thanks in advance all!!

 

[JohnW2]

My following question is whether I can legitimately replace the offending switch with this: http://www.screwfix.com/p/lap-13a-switched-fused-connection-unit-brushed-stainless-steel/31552 and then replace the fuse with a 3A variant?

From what you say, it sounds as if the simple answer is 'yes'. It sounds if either an unused cooker circuit has been used to supply the boiler or that the 45A cooker switch was all that the installer had available!

Is this work notifiable

No.

One last thing to note is that the boiler switch is not on the RCD protected circuits. From what I have read, I don't believe this in itself is a problem, but it would be great to confirm from someone more in the know!

There is no regulatory requirement for a hard-wired connection to a boiler to be RCD protected. Nor is there a regulator requirement for any existing buried cables to be RCD-protected, even if there would be such a requirement if they were new cables.

Having had very little time at home this week, I've yet to check which MCB the boiler is actually on, but I expect that the 3A manufacturer recommendation is being exceeded nonetheless!!

IT is obviously crucial that you determine what MCB is supplying the boiler, in order that you can switch it off. From what you've said, it would not surprise me if it is labelled at teh CU as a 'cooker' circuit, quite probably with a 32A MCB. That, in itself, will not be a problem if, as you propose, you install an FCU with a 3A fuse.

Kind Regards, John

 

[EFLImpudence]

As far as I am aware, this existing setup is not adhering to this?

It would seem that is the case but there could be a fuse somewhere else.

My following question is whether I can legitimately replace the offending switch with this: http://www.screwfix.com/p/lap-13a-switched-fused-connection-unit-brushed-stainless-steel/31552 and then replace the fuse with a 3A variant?

Yes.

Is this work notifiable

No.

or would it come under maintenance

To be pedantic, it doesn't come under anything apart from not notifiable.

One last thing to note is that the boiler switch is not on the RCD protected circuits.

Doesn't matter. The RCD requirements relate to cables not accessories nor appliances.

I've yet to check which MCB the boiler is actually on, but I expect that the 3A manufacturer recommendation is being exceeded nonetheless!!

Yes, it could be the cooker circuit, I suppose, which doesn't matter but you may want the switch for a cooker.
If so, you could put a fuse for the boiler somewhere else.

 

[ray.birch]

John, EFL, these responses have been incredibly helpful (and QUICK!).

Many many thanks to the both of you.

 

[winston1]

The boiler will have its own internal fusing. Any downstream fusing is only for protection of the cable which will be rated at more than 3amp. Probably 16 amp as Valliant is a German boiler plugged into Schuko sockets in its home country. So you can ignore their instructions. However a 45 amp cooker circuit is too much.

 

[JohnW2]

So you can ignore their instructions. However a 45 amp cooker circuit is too much.

No-one has suggested that it is a 45A circuit. If it is an old cooker circuit (we're no sure_, most likely it's a 32A one, but there would still be a need for fusing down to protect the 'bolier cable'. However, once one has decided that one needs a fuse, it might as well be 3A.

Kind Regards, John