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Replacing Honeywell ST699 Programmer with ST9100C Model

Discussion in 'Plumbing and Central Heating' started by williamscadwern, 4 Mar 2012.

  1. williamscadwern

    Joined:
    4 Mar 2012
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    Location:
    Gwynedd
    Country:
    United Kingdom
    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
     
  2. 45yearsagasman

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    14 Mar 2010
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    Location:
    Norfolk
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    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)Please login (registration is free!) to view this link.
    http://www.google.co.uk/url?sa=t&rct=j&q=honeywell+wiring+diagrams&source=web&cd=8&ved=0CF0QFjAH&url=http%3A%2F%2Fwww.honeywelluk.com%2Fdocuments%2Fall%2Fpdf%2Fwiring%2520guide%2520issue%252016.pdf&ei=PypTT7b5H4bp8QOv6NDxBQ&usg=AFQjCNFoF8kBJG_Ukn4EQ9iJiESbkpX1kg

    You can down load from this.
     

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