Controller replacement

1 Mar 2011
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United Kingdom

Have a Y plan honeywell system, with a ST699 controller.

Am considering replacement with one of these - a combined controller and wireless room stat (dont have a room stat currently).

It says it is compatible with many industry standard backplates.. anyone know if it will plug onto a ST699 backplate please?


EDIT: "a wireless enabled programmer the ST9420C and a wireless thermostat the DT92E"
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The ST699 does not have the industry std back plate and will require a rewire.
There may well be instructions contained with the kit.
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BTW will be fitting this to work with a old ideal mexico 2 boiler which is running fine.. i assume it doesn't matter what the boiler is, but is that a fair assumption?
Doesn't matter which boiler. If you are comfortable doing a bit of wiring it won't be difficult to change over. The will be instructions on how to wire it up and which terminal is which, compared to the ST699. It you are not confident with this then better not to touch it.
Thanks again!!

I read the instructions and there is a equivalent wiring table for the ST699 so it looks fairly straightforward.

Seems like a good controller too so i may go for that i think.

Has anyone fitted one of these controller/wireless stats - my existing controller st699 is a bit suspect (programs come on outside of the timed times) and so i don't mind spending a bit to replace both controller and install a stat at same time, but want to make sure i invest in a good un..


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