Replacing Honeywell ST699 Programmer with ST9100C Model

[williamscadwern]

I have a twelve month old CH/HW system that comprises a Gloworm 30 Sxi Boiler which serves a heating system on wireless thermostatic control and hot water from a cylinder via an actuated valve system and cylinder stat. The wiring to the ST699 controller appears to be in the Sundial C plan arrangement although the elements are mix and match not a Sundial pack.

The first part of my question is can I replace the ST699 programmer with a ST9100C (which I already have).

Secondly how complicated a re-wire is needed and where can I get a guide to re-wiring.

Thank you

 

[45yearsagasman]

It won't be a C plan with that boiler. See what motorised valves you have and go to the Honeywell web site for all the diagrams.
2 x 2 ports = S plan
1x 3 Port= Y plan (most likely)http://www.google.co.uk/url?sa=t&rc...6NDxBQ&usg=AFQjCNFoF8kBJG_Ukn4EQ9iJiESbkpX1kg
You can down load from this.