Boiler not firing

Discussion in 'Valves & Taps' started by Swale, Nov 29, 2016.

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  1. Swale

    Swale New Member

    Hi all
    i would really like some advice please
    2 zone heating 1 upstairs 1 downstairs on an ideal combi boiler
    2 Honeywell cm707 programmable stats one for each valve
    wired to Honeywell junction box(wiring centre) as follows
    perm live from fused spur to term 1
    perm live from term 1 to boiler
    perm live to both stats in term 1
    perm live (grey) to both valves in term 1
    All neutrals in term 2
    all earths in term 3
    the stats have the perm live going in term A with the
    return term B out of stat (black) going to wiring centre in with brown upto valves
    orange from valve back to wiring centre with a grey going to boiler s/l
    each black from stat go into a separate terminal 4 and 6 with a brown from the valve

    when the stat is pumped up for heat the valves open but boiler does not fire is the wiring correct
    the valves are Drayton any help much appreciated thanks
  2. rpm

    rpm Trusted Plumber Top Contributor!!

    Mr Swale of Swale Heating, currently taking a bashing on another forum?
  3. Rickster123

    Rickster123 Guest

    You're such a forum tart!!!

    I nearly joined swale about 18 years ago..
    • Like Like x 2
  4. SimonG

    SimonG Plumber

    Use a tester to check power at necessary points. Simple s plan.
    • Like Like x 2
  5. rpm

    rpm Trusted Plumber Top Contributor!!

    • Like Like x 1
  6. Swale

    Swale New Member

    Hi Iam not mr swale Iam a new build installed trying to get my head round this 2 zone heating that contractors want in, never done it before, swale is the river next to me
    • Like Like x 1
  7. Swale

    Swale New Member

    Thanks for reply, 240v at both terminals 4-6
    240v at terminal 10 orange x 2 and s/l grey upto boiler
    240v at boiler perm live and switched live when stats are on
  8. Masood

    Masood Guest

    Sorry, I'm finding it hard to visualise what you're describing. A photo or diagram would be really helpful.

    Alternatively, take a look at the Honeywell website for a standard S-plan system which is what you're trying to configure. Follow the diagram and you won't go wrong. Terminal numbers and wire colours aren't that important, just follow the switching sequence..
    Last edited by a moderator: Dec 3, 2016
  9. joni os

    joni os Plumber

    Use multimeter not volt stick. If perm live and s/l going to boiler are both 240v. then, other than checking fuse on PCB, you will need GS engineer.