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Discuss Honeywell wireless not binding!!! in the Central Heating Forum area at UKPlumbersForums.co.uk.

  1. Marty28k

    Marty28k Guest

    Hi, at the best time of the year, I discover that my honeywell st9420c has lost its wireless connection with the room stat and now will not 'bind' with the unit. Following the instructions both units correctly go into the binding mode but it never compleates successfully! Anyone with know or similar experience please advise, Thanks
  2. mountainman

    mountainman Plumber GSR

    I hate wireless controls.

    Have you put new batteries in the sender unit?
  3. Marty28k

    Marty28k Guest

    Yes, new batteries, units are next to each other so its not a distance thing, I'm beginning to dislike too, but its only about 16months old!!!!
  4. mountainman

    mountainman Plumber GSR

    A new unit is required methinks.
  5. Dan Masey

    Dan Masey GSR

    yep i had this mate with mine, i contacted honeywell directly, they sent me an email of a step by step guide which they do not put in the user guide or manuals online.

    here it is.



    Ensure the slider is in RUN

    Press and hold +, - and Heating mode buttons for 8 seconds

    BIND MENU will show briefly, followed by first binding display

    Use + and to select the Radiator symbol, Press OK

    If display shows -- -- - - nothing bound
    If display shows bnd something already bound

    (If you want to cancel existing binding press OK for 8 seconds and the display will say RESET for a few seconds), then

    Press OK to put in binding mode, display will flash BINDING ready to receive, ---- will flash


    Hold DT92E approximately 1 metre from ST9420C
    Press and hold the power button for 2 seconds
    Hold the and for 3 seconds until Inst is displayed
    Press and the display shows Cont
    Pressing the 3 times and the display shows CLr
    (Press the power button until --- if you want to clear existing binding data)
    To put into binding mode press the display will show Cont
    Press power button to send binding message display will show Sync up to
    4 minutes

    If binding has been successful bnd will be shown on the ST9420C and display will show COMPLETE for a few seconds and bnd will stop flashing

    If the binding was unsuccessful the ST9420C will show ---- flashing

    To exit binding mode put slider to RUN on the ST9420C.
  6. mountainman

    mountainman Plumber GSR

    Jeez, I'd run a cable and fit a wired 'stat.
    • Like Like x 2
  7. happyflyer

    happyflyer Guest

    You mean in the time it takes to bind???
  8. Marty28k

    Marty28k Guest

    Thanks Dan, these are the instructions I followed. It just never actually successfully binds. Just continues to flash as if both units are still looking for each other, ending up timing out after 10 mins or so. I have been over it so many times, they must be a fault but in the controller or the room stat, who knows?
  9. lame plumber

    lame plumber Plumber GSR

    change the frequency settings, could be a new computer wireless unit interfering,
  10. happyflyer

    happyflyer Guest


    How many different channel are there on these units.
  11. Marty28k

    Marty28k Guest

    Lame, how do I change the frequency settings?
  12. happyflyer

    happyflyer Guest

    Yes Lame can't see it in the destructions
  13. happyflyer

    happyflyer Guest

    You mean on the computer???
  14. PETE 123

    PETE 123 Active Member

    Had something like this in the end i took prog off plate waited 5secs and replaced back on wall plate and it worked
  15. lame plumber

    lame plumber Plumber GSR

    most rf units have dip switches to allow you to change the freqency used,
  16. Marty28k

    Marty28k Guest

    While I'm here,[TABLE="width: 100%"]
    [TD="colspan: 2"]does anyone have any experience with megaflow units. I was wondering if they could operate without a controller, as they do when you use the electrical element. The internal stat can call for the boiler so is it actually possible to wire so its on constantly?[/TD]

  17. happyflyer

    happyflyer Guest

    Don't understand a word of this Marty, a Megaflow heating coil should be controlled by a two port valve via a spare thermostat inside the unit, go look at the datasheet, the immersion heater has a separate internal thermostat
    I am not certain what you are trying to achieve here with the question, maybe someone else can
  18. mountainman

    mountainman Plumber GSR

    Don't tamper with a Megaflo Marty unless you are qualified to work on them.
    Your post suggests that you are not.
  19. happyflyer

    happyflyer Guest

    Well there you are Marty take his advice leave well alone or Boooooom:6:
    • Like Like x 1
  20. Marty28k

    Marty28k Guest

    Sorry Happyflyer, I should have explained it a litter clearer.
    Thanks for your concern mountainman, Im only asking for information about plannning possibilities, I definitely will not be doing any tampering, however as previous topic, Im having loads of issues with my current setup and was wondering if I could take the megaflow out of the equation by get it running without the use of the controller. i actually didn't think it was that complicated and the controller only turns it on and off at lib when reaching a desired temp. I was under the impression that the megaflow could do this itself anyway, as it can operate itself funder immersion? Is that a littler clearer?
  21. happyflyer

    happyflyer Guest

    If you are only talking about heating the megaflow off the immersion heater there are no problems, I thought you were talking about messing with the controls to the water coil in the Megaflow
    the megaflow does have a temperature and pressure safety valve built in it such that it the control to the coil or the immersion heater failed it would blow off, I still don't know what you mean
    and you are not explaining it very well.

    The immersion heater has a built in thermostat that you can adjust up and down you can connect this to a time switch if you wish
    The water coil heats the MF up via a boiler and a control valve, there is an internal spare thermostat that this valve is wired to

    Good advice would be to stay clear, unless you can before much more specific.
  22. Marty28k

    Marty28k Guest

    Ok, I have the following
    Megaflow (from boiler not immession)
    Pressurised Heating System
    Controlled by a Honeywell wireless sundial pack 3
    Y Plan

    So at the moment to get hot water, the controller is set to constant, its connecting to a wireless honeywell cylinder stat thats sitting in my garage not connected to any cyclinder so its basically telling my megafow to be on all the time. The megaflow (i guessing but the internal stat) calls for the boiler when needed. The boilers comes on and off as water is used and temp drops in the cylinder. I know the controller should be doing this job, but honeywell don't support megaflow cylinders. And it is working, except not the way it meant to. For this to work it is relying on the wireless communications between the devices, and this has been failing recently for some reason. Most of the problems is with the room stat, but I can force the heating so Im not too bothered, but the heating is a bigger issue. I have contacted honeywell who are helping me fix the binding issues between the wireless devices, but if possible I would like the megaflow to operate constantly without the need to be told from a controller.. I would have thought this is possible as its pretty much doing it all by it self now, but maybe not as you guys know best. I hope thats cleared it up?
  23. chris watkins

    chris watkins Plumber

    What is perfectly clear Marty, is whoever installed your system, both the controls & the MEGAFLO CYLINDER did not know what they where doing.
    As the Law requires anyone who works on these un-vented hot water system to hold the un-vented / Part G ticket, we can not provide advice which would encourage you to break the Law & endanger yourself as well as the people around you. As others have said these thing can be very dangerous if you don't know what you are doing.

    So please, get someone in who is qualified, all I can say is you should not have a Y plan system (unless other valves are installed) & the internal Megaflo stats MUST be wired up correctly, Honeywell have already told you the two are not compatible, so take the advice.
    • Like Like x 3
  24. Masood

    Masood Guest

    I understand what you're trying to achieve and it's possible but dangerous. You need to have both time and temperature control on your unvented cylinder.

    It sounds like you'd be better off getting someone who understands controls wiring to come and give your system a once-over, with wired stats rather than RF!
  25. Marty28k

    Marty28k Guest

    Masood, thats the best advice I've heard so far, however as Chris points out, and in my experience, no offence to all involved plumbers and generally not the most experienced at wiring. Is this your field or can you recommend someone, as originally written i was never going to do anything myself but only asking for planning and also to ensure i understand what needs to happen so when i call someone in to do it, i understand that they are actually doing the job correctly as most of the time, its not! Even from forum to forum its amazing the difference in responses you get!!!!
  26. Masood

    Masood Guest

    Marty, if you post your location in the "I'm looking for a plumber" section of the forum one of our members is bound to be local to you. If you're in London, Essex or Herts kind of area please PM me your phone number and I'll be glad to help. I'm pretty good on the wiring side of things and actually enjoy it!
  27. Marty28k

    Marty28k Guest

    Last edited by a moderator: Nov 9, 2013
  28. lame plumber

    lame plumber Plumber GSR

    not sure where your coming from there but the best advice has been given in that you need your system setting up properly. You cant understand it yourself and have to rely on the fact that those coming in do, and its obvious whoever installed your sytem either got it badly wrong as they had never done any training or read the instructions either. Alternatively you may just not understand how a correctly set up system works, and I'm hoping thats the case this time and a decent heating technician could come in and check it over and explain it to you in an hour quite easily. forget the tv shows as there are many more decent people working out there who tar the rest of us unfairly.
  29. vulcanbomber

    vulcanbomber New Member

    Does anybody know where is the heating mode button on the ST9420C so I can check that the remote is bound to it?