Honeywell ST9400C 7-Day Electronic Programmer with 2-Channel

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Honeywell ST9400C 7-Day Electronic Programmer with 2-Channel

Will this programmer be a direct replace my Honeywell CM 907 ?

I have the Honeywell Y plan CH.

Don't want to jump in and buy the wrong replacement

Thanks

John
 
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Honeywell ST9400C 7-Day Electronic Programmer with 2-Channel

Will this programmer be a direct replace my Honeywell CM 907 ?

I suspect not - the ST9400C is a programmer (timer, or rather two timers, to you and me) whereas the CM907 is a programmable thermostat (a combined timer and thermostat) so if you did swap it you'd be losing the thermostat aspect (and gaining a second timer!).

Do you want to elaborate more about the current setup and what you're trying to achieve?
 
I suspect not - the ST9400C is a programmer (timer, or rather two timers, to you and me) whereas the CM907 is a programmable thermostat (a combined timer and thermostat) so if you did swap it you'd be losing the thermostat aspect (and gaining a second timer!).

Do you want to elaborate more about the current setup and what you're trying to achieve?


We need a Thermostat as this CM 907 has been great also used as a timer.

Just upgrade, so replacing.

If the ST94000c does not have a Thermostat then thats the wrong one for us.

Any suggestions as replacement timer and thermostat
 
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We need a Thermostat as this CM 907 has been great also used as a timer.

Just upgrade, so replacing.

If the ST94000c does not have a Thermostat then thats the wrong one for us.

Any suggestions as replacement timer and thermostat

Thanks for that additional info. Still need a bit more though to provide a recommendation! ;)

With this being an 'upgrade', what aspects were you wanting to improve upon and, noting you've been pleased with the CM907, what aspects of its functionality were you pleased with?

Whilst all programmable thermostats essentially fulfil the same role, it is the nuances between them that can make one 'better' than another. But it's horses for courses, for example whilst I might appreciate the TPI implementation on a Honeywell others might really dislike it, I might wish for remote access but others don't and where another might desire integration with electronic TRVs I might see no need etc.
 
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Thanks for that additional info. Still need a bit more though! ;)

With this being an 'upgrade', what aspects were you wanting to improve upon and, noting you've been pleased with the CM907, what aspects of its functionality were you pleased with? (And why upgrade it?)

Whilst all programmable thermostats essentially fulfil the same role, it is the nuances between them that can make one 'better' than another. But it's horses for courses, for example whilst I might appreciate the TPI implementation on a Honeywell others might really dislike it, and where another might desire integration with electronic TRVs I might see no need etc.


The temp setting buttons don't seem as responsive, you have to push hard to select temp, sometimes it reverts back to original setting if that makes seance .

You are up early for a Sat.

thanks, MJN & pcaoulte
 
The T4 is a straight swap for the CM907. It isn't an upgrade in terms of the features offered. By default the T4 it is supplied with 4 programable temperatures per day rather than the 6 per day that the CM907 offers, the T4 can be changed to 6 programmable temperatures per day in the installer settings.
 
The temp setting buttons don't seem as responsive, you have to push hard to select temp, sometimes it reverts back to original setting if that makes seance .

You could ways just replace it with another CM907? Whilst they might have been superseded now they are still available. If you were willing to give it a go you could also take it part and see if the button contacts need cleaning (although I'm not sure about the setting reversion that you mention). As @pcaouolte says though, the T4 would likely be perfectly acceptable and simply give you a newer replacement for what you're used to.

You are up early for a Sat.

Oh don't remind me. That's 4yr old daughters for you... although I suppose it could be worse!
 
You could ways just replace it with another CM907? Whilst they might have been superseded now they are still available. If you were willing to give it a go you could also take it part and see if the button contacts need cleaning (although I'm not sure about the setting reversion that you mention). As @pcaouolte says though, the T4 would likely be perfectly acceptable and simply give you a newer replacement for what you're used to.



Oh don't remind me. That's 4yr old daughters for you... although I suppose it could be worse!

I do like the way the CM 907 pulses to the temp e.g. set to 21 and as temp go's up 19:5 -- 20 to correct temp this seems to save heating , as long as the T4 does the same that would be great.
 
It's called TPI (Time Proportional Integral), it is supposed to save energy. The T4 has it similar to the CM907.


Then thats the one for us.

While the CM 907 is working it's the time of year you don't want breakdowns, and the old girl is getting old.
Thanks
 
Have you fitted new (preferably lithium) batteries?
 

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