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Hi. I have a ST6400S HONEYWELL PROGRAMMER and cant reset it after my boiler service so I can only have my heating on for an hour at a time!! can you help?

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  • fletch65 Apr 18, 2008

    SNAP - same problem ! looking on internet but haven't found anything - if I do I'll let you know.

    Sounds like this model is used by landlords and prevents overdue services and recommeds that honeywell reset it ( at a cost of course ) but we have it in a normal everyday house - surely we don't need honeywell just to reset !


  • patch04 Jul 12, 2008

    The manual refers to special key sequence that is required and refers to a leaflet EN0R8542 which surprisingly does not come with the main manuals. Very dissapointed if i need to get a honeywell representative to come out, as it will be cheaper to replace the unit completely. What a con!

  • Anonymous Feb 19, 2009

    please can anyone help as anyone got the sequences


2 Answers

The only way to get the key sequence is to contact honeywell tech support, they will give you the sequence over the phone as long as you are a contractor (or pretend to be one), but they will not send out any literature on it. If you live in an owner occupier dwelling then it has been fitted by mistake, and the best thing is to replace it.

Posted on Sep 10, 2008

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Hi - I have a sort of solution !!!!!!!!!!!

take if off and smash it and replace it !!

I went to our local electrical supplier and asked about this problem and he said that he'd had lots of people complaining about this issue and many many more. The builders who fitted it didn't know about the problems but electrically wholesaler's did !

We now have a Danfoss which fits nicely over the backing plate so no big holes in the wall and works a treat - there is an option to set it for landlords on this new one but you have to contact them and ask them to come out and set it up - NOT the other way around.

Sorry it's not the answer you wanted - but we took the unit the bits to see if we could get around the prob but couldn't !


Posted on Apr 19, 2008

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