combi boiler controller

This is the sort of thing you want:

Fitting is simple as the receiver goes near the boiler and only needs a live feed from the boiler terminal strip and the other two connections replace the link on the terminal strip.

I am in the same predicament as you and am looking for a timer, try

Tom

Any timer will do. Favourite round here is the Honeywell CM67 programmable thermostat which allows you lots of control and will save you money if you use its facilities to best effect. The wireless RF model will save you having to run a cable from the boiler to the preferred position, though you might want a check from someone here as to how well the radio signal through brick walls.

Depends of the combi and how competent you are. For the CM67RF, a mains supply and two wires into the combi across the call terminals.

Do you have a rooom thermostat. One should have been fitted. If so replace it with a Honeywell CM67 with the optimisation.

Whilst the CM67 has become something of a classic (deservedly so) it looks like Honeywell now have something to take its place - the CM907 (CM900 series in general).

Mathew

It doesn't mention optimisation. I prefer the Landis & Steafa version of the CM67. They make better equipment too.

It does provide optimisation (in the main spec list).

Mathew

Incidentally, I see that both the CM67 and CM907 have optimisation disabled by default - and can only be enabled within the installer menu which is certainly not intuitive to enter and hence probably left that way in a lot of cases...

Mathew

If it is then it is a *very* recent change. The optimisation is definitely enabled by default on the CM61 and CM67's in both normal and RF versions and has been for some years.

Are you sure? I first noticed it on the CM907 installer sheet and happened to notice the same on the CM67RF:

Page 3 of

I was surprised given it's such a useful/beneficial feature but then I wondered if perhaps it was found to be causing confusion to end users i.e. why's my heating coming on before I asked it to?, or my heating comes on at different times each day - what's wrong?

Mathew

Hmm... According to

But the CM907 definitely also says disabled...

Mathew

I turned it back off on mine after experimenting: several times I found that it had turned the heating on far too early.

In buildings with a low thermal mass, they can be fooled into bringing in the heating far too early. I recall one in a large wooden Scout hut that brought the heating on at 2:00 a.m.

What were you doing in a Scout hut?

Testing an optimiser. Boy you are dumb.

At 2am as well..? ;-)

Dib dib dribble...

Is that what they call it these days?

Baden Powell would turn in his grave if he knew.

I know your sort. You are into rubbing two boy scouts together.