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I have a honeywell st6100s, i have just had it serviced, but it still flashes up service due and reads off and the timer can not be set

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Normal 0 This unit can be reset, just a little complicated thats all.
Firstly, move slider to 'set program'. Then, on the left of the unit are two buttons, 'override' & 'extra hour'. Press and hold both together 'till 'inst' shows on the panel ( about 5 seconds ).
Then ( lots of fingers required! ) press and hold the two buttons mentioned above, along with '-' '+' & 'next on/off ( total of five buttons! ) until the user menu flashes up.
Now scroll to AL, which is probably showing a value of '1', this wants to be changed to '0' to turn off the 'service due' warning. To save this value, press and hold the first two buttons once more and then simply move slider back to 'run program'.
Job Done!!!
I hope this helps. It should certainly remove the annoyance of having to phone your housing association and then sit around waiting for them to show!!

Posted on Jan 04, 2009

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