HONEYWELL CHRONOTHERM CM61

[Jaybee 45]

Hi folks,

Can someone tell me if I can replace an older style central heating timer, (which only allows water and /or heating to come on and off just twice a day) with a Honeywell Chronotherm CM61.
The heating system is a Baxi I think, with a gas fire in front and a storage water tank upstairs. I am not going to try changing it myself (dont like electrics) but I have seen one at a good price and wondered if it is compatible.
I have the Honeywell in my own home and find it brilliant but that's with a combi boiler. The replacement is for a rental house.

Any advice much appreciated.........Blod

 

[45yearsagasman]

It probably is compatible,but the boiler is not the governing factor.You need to describe the type of system controls you have.

 

[Jaybee 45]

Hi 45yearsagasman (what a mouthful!!) Thanks for the reply. Without actually going to the house I will try to describeit. The box is brown with time dial. This has to be programmed by slotting orange clip for start and grey clear clip for stop time. This can only be done twice in 24 hours as there are only two sets of plastic slotting clips on the 24 hour dial. It is run off a mains point and you can have water and heating together or just water. You cant have just heating. It is about 20 years old.

New info!!!! The old timer is a Switchmaster 400

Hope this helps
Regards Blod

 

[D_Hailsham]

Can someone tell me if I can replace an older style central heating timer, (which only allows water and /or heating to come on and off just twice a day) with a Honeywell Chronotherm CM61.

1. The CM61 is an obsolete model, which is why it is cheap.

2. The CM61, and its replacement the CM927, only controls the heating times/temperatures; it does not control the hot water times/ temperature.

The heating system is a Baxi I think, with a gas fire in front and a storage water tank upstairs.

That's a back boiler - boiler is hidden behind the gas fire in the fireplace.

Can you turn the hot water on, by itself, in the winter? Or does the heating always come on at the same time? If so, you have what is called a gravity hot water, pumped heating system.

I am not going to try changing it myself (dont like electrics) but I have seen one at a good price and wondered if it is compatible. ...The replacement is for a rental house.

In which case I would advise you to get in a heating engineer who does electrics and ask for his advice - the solution may not be straightforward..

 

[Jaybee 45]

Just found your reply. Yes I can get hot water only but not heating only. Yes it is a baxi bermuda back boiler.
The reason I asked about aCM61 is because I have this in my house and find it excellent.

 

[D_Hailsham]

Just found your reply. Yes I can get hot water only but not heating only.

In that case, a CM61, on its own will not be sufficient.

You need to get someone in to advise on the best solution.

 

[Jaybee 45]

Thanks for your advice. Much appreciated.

 

[snb]

yes you can use the cm61 wired to an older system controls which are set up as you state.

the cm61 is then used to replace the current room stat.

Very simple to do for someone who actually does this type of work daily rather than some who just read literature.

the cm61 was replaced with the cm921
cm67 was replaced with cm927.

would always recommend the 927 over the 921 as it gives you 7 day control