Programmer / 2 gang switch?

[amstel]

Hello all,
I have a Glow Worm 24 hxi boiler, open vented system, 2 honeywell zv's, honeywell room and cyl stats, S-plan wired, with a st699 programmer.
This system works perfect, no problems at all since it was fitted 12 years ago.
However, the HW and CH selection sliders are getting very loose, and just looking ahead at a possible failure of the programmer, and bearing in mind we have never once used the timer facility, is it possible to replace the st699 with a 2 gang light switch for ch and hw?
There are 4 wires at the programmer...L, N, cylstat, roomstat,
If not poss, then its a new programmer at £80 ish.
Thanks and a HNY to all.

 

[Echo the husky]

A programmer is of course the preferred option as it allows all functions. I have fitted a pair of illuminated engraved grid switches before one for HW one for CH, in a 2 gang grid plate, for a 95 year old who also never used the time functions, and could not see well enough to read the little LCD display on the old programmer.

Such a setup would be against Part L of the building regulations though, and I would not recommend it.

 

[stem]

Yes you can do it technically, but it's not good practice. There are programmers that cost less than £80.

Here's a sketch for you.

Earths to be terminated as applicable

Edit. Sorry I just noticed that you said it was an S Plan, so it won't have a hot water 'off' wire.

 

[amstel]

Yes you can do it technically, but it's not good practice. There are programmers that cost less than £80.

Here's a sketch for you.

View attachment 111378

Earths to be terminated as applicable

Edit. Sorry I just noticed that you said it was an S Plan, so it won't have a hot water 'off' wire.[Thanks Stem, that looks easy enough, as long as it works and safe I can't see why it's not good practice, thanks again.

Yes you can do it technically, but it's not good practice. There are programmers that cost less than £80.

Here's a sketch for you.

View attachment 111378

Earths to be terminated as applicable

Edit. Sorry I just noticed that you said it was an S Plan, so it won't have a hot water 'off' wire.

 

[amstel]

Thanks Stem and Echo, easy to follow diagram, I can't see why its not good practice, is it because of no timer arrangement?
Cheers.

 

[Echo the husky]

Yes, meaning it is likely to be left on more than it needs to be, increasing fuel consumption.