Grasslin timer for Baxi combi boiler - wiring help needed

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26 Sep 2007
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United Kingdom
Hi in need of urgent help as Im completely mystified why my timer wont bring on the boiler weve just had fitted and ive tried everything I can think of but to no avail ......
Weve had a BAXI combination boiler fitted and ive got a Grasslin QM1 analogue timer which is basic or so I thought ......Ive got a 4 core coming from the boiler to the timer which goes into N , L , E then it has numbers 1,2,3,4 and the diagram says 4 is the "on" so ive put the sw line in there which goes to the number 2 terminal in the boiler which is the external input terminal and I removed the link in the boiler which the manual says between 1 and 2 if your having an external timer .............
Basically when I turn the supply on ive got 240 on the backplate so ive put the cover on flicked it to "constant" but nothing the LED doesnt even light up ..........Ive brought the timer back and changed it for one of the same thinking it might be a dud but same problem ....

Any help whatsoever would be greatly appreciated as I cant figure out why it wont switch on as its a very basic system no stats or anything

cheers lads

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Thanks for reply Baz and getting the instructions up for it no I havnt put that link in because it says thats for a gravity fed system which mine isnt however would you think that would work ? I aint got no stat either probably worth a try wouldnt do any damage would it ?
On the timer 2 3 and 4 are volt free switching , what ever goes in on 3 will come out of 4 when on.
As baz says
Therefore you need to link L to 3 so the live comes out of 4 when it is on
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Ahhh I see cheers Rocky nice one I was thinking it was something silly just never played with boilers before ill give that a whirl

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