Central Heating programmer

[andrewjo]

Bear with me on this one, sounds more complicated than it is!

With my current central heating programmer, I cannot time the ch and hw to come on independently of each other, although I can switch off the hw and have just the ch on, or vice versa. I want to renew the programmer for one which allows me to switch on and off the hw and ch at different times to each other. The current programmer is a Honeywell ST699 and is square in shape. The programmer is positioned on a tiled wall immediately to the left of acouple of electrical outlets. In other words there is space to the left of the programmer but not to the right of it (as you face it).

Programmers which can control the ch and hw fully independently, appear to be all oblong in shape. This in itself is not a problem, but the fitting for the standard backbox is on the left of these programmers (as you face the front of the programmer). This means I cannot use one of these as they will overlap the existing adjoining electrical outlet. My problem is that I need to find a new programmer which can control the ch and hw independently BUT will not overhang the existing electrical outlets. ie, the backbox is on the opposite side, or the programmer is square. Can anybody help please?

 

[oilman]

You could try moving the mounting plate to the left, or remove one of the sockets.

 

[ChrisR]

Keep you programmer, but put its CH setting "on 24 hrs". Then change your room stat for a programmable one. From Screwfix about £30, or a proper one (Honeywell CM67) more like £80 I think. But it's the bee's *******s.

 

[andrewjo]

Thanks oilman, but due to lack of space and the work involved (electrics/tiling) I was hoping to avoid that option! I was hoping somebody might be able to point me in the direction of a suitable replacement programmer, or at least tell me if programmers are manufactured the "other way round" (left/right handed back box).

Interesting suggestion ChrisR, will consider, thanks!

 

[Engineer Lane]

Andrew,
I have fitted one of these 7 day programmable room stats, and they are brilliant.
My CH is on 24hours at the programmer - and at the stat - different temp settings for different times of the day. eg night from 0001-0415 18 deg, morning 0415-0830 20 deg, weekday "day" 0830-1630 19 deg (weekend "day" 20 deg) evening 1630-0001 20 deg.
As my wife works Thurs and Fri only, and I work shifts, our workdays are set as Thur and Fri, and the other days set as rest days.

The hot water comes on and off per the programmer.

Best £50 odd I have ever spent.
Paul

 

[andrewjo]

Thanks for your comments Paul. It looks like the programmable room stat is the way to go!

I have a simple room stat at the moment, with just a dial on it for the temp. Is it easy to replace it with a programmable one, ie, is all the wiring the same? Or is there more to it than just removing the old one and screwing a new one in its place?

 

[Engineer Lane]

Andrew,
They are a doddle to fit.
I cannot comment if the wiring is the same, as it depends on what you have currently, but mine was pretty much like for like - used 2 wires of the 3 present (one was used on the original original stat - and was a supply for the internal "heater" - this had been removed when the stat was 1st replaced).

Paul

 

[ColinYounger]

Further to this topic, I have a very old Switchmaster SM300 controlling the heating, and just below a simple on-off switch to control the immersion heater. Both are on 3amp fuses.

Hot Water 24-7 sounds fun, but isn't when the Leccy bill comes in.

Is it posible to convert these two 'controls' to a new digital controller so that we can have hot water and heating separate? The information I've read in B&Q oops isn't particularly helpful.

At the very least, how can I add a timer to the immersion?

 

[andrewjo]

Colin I don't know about combining the existing two controls into a new digital controller, but you can buy a timer to replace your immersion heater switch - they sell them everywhere, diy shops etc, even at Argos. You just unscrew the front plate of the switch, "unwire" it and replace it with the timer.

 

[ColinYounger]

you can buy a timer to replace your immersion heater switch

Great - thanks!

Your phrasing is interesting , though; is there a special type of timer that is required, or is it a 'bog standard' timer?

 

[andrewjo]

They are not special, just make sure you get one that can cope with the current required for an immersion heater. Go to www.screwfix.com, search for "timers", and you will see some examples.