Mechanical Timer on a Baxi Combi 105E

[martinwalsh]

When my plumber fitted my new Baxi boiler he didnt fit a timer. I phoned him and he said i could fit one myself easy enough. Ive bought the 24 hour mechanical timer and fitted per instructions and yes it was easy enough, HOWEVER now my central heating wont come on at all even if set to constant. The timer is running and the time is shown correctly, its wired correctly but no heating. Is there some rewiring or movement of jumpers on the PCB that i need to do? (cant see anyhting in manual) or do i have a duff timer.

Just found a comment on the cover to the PCB that stated if im fitting external controsl i have to do rewiring, but this isnt an external control is it?

 

[compheat]

It could be a faulty clock I've just had the same problem and it was third time lucky before i got one that worked.

 

[ricarbo]

In my opinion, an external mechanical timer is an external control.........
After all, it's external and controls the boiler!!!!!!!!!!
So is a wall stat
Don't know your specific application , but some boilers require both a permanent live supply and a timed supply. The permanent supply is required to allow the boiler to control the pump and may be neede vy the boiler electronics for correct operation.
If this an installation under current regs, a timer is required by law. was the installer competent???

 

[Gasman1015]

No, it is'nt an external control and if you are sure you have wired it correctly
then it must be duff.

 

[martinwalsh]

swapped for a digital timer this morning and all is well, a duff. thansk for your help