Programmer Probs

[eswtr]

having just moved into a new house i have decided to replace my switchmaster programemer (that was falling off the wall).
i ve bought a drayton SM2 programmer, which also has a 24 timer, with on,off,once or twice setting for both HW and CH.
i was going to just change over the wiring for the relevant Live, Neutral, Earth 1,2,3 & 4 sockets, yet within my original unit, the CH off wire wasn\\\'t wired to 2 as label on the unit but strangely to the neutral?, yet the system still worked fine.
yet wiring the new programmer in the same way doesn\\\'t let the CH work off the timer (just on manual demand).
Thinking the original wiring was wrong i changed the CH off from the neutral back to number 2 as indicated on wiring diagram, yet this still doesn\\\'t allow the CH to work off the timer. just demand only!
can any suggest a solution as how to make the new unit work on the timer controls, or is the new programmer not compatable or even broken?

 

[ollski]

what sort of valve and system do you have...mid position, diverter, s-plan? etc, or at least a bit of a description of brands and models of some components. The ch off is not very often wired in, you would really need to trace the wiring through with a multimeter.

 

[eswtr]

i think i have a mid position, pumped system. the pump (danish - gronfos, i think) is with the cylinder (this has a thermostat) in the first floor airing cupboard. while i also have a boiler(best) in the garage. i also have a room thermostat in the hallway (fitted in series with the pump - i think). and as metioned b4 in the kitchen is the programmer. before it was a switchmaster 805 (old and broken) and ive know got a draytom SM2.
as for the wiring, being a new house and mostly hiden its hard to tell the full arangement.
The wiring of the old switchmaster:
Presummed wiring arrangement
----------------------------------------WIRE A - Power
----------------------------------------WIRE B - Pump
----------------------------------------WIRE C - Boiler
----------------------------------------WIRE D - additional spur to other
---------------------------------------------------local appliance??
---------------------CH--------HW
-------------------ON OFF ON OFF
---------L-----N---1---2-----3----4
--------AD---AB--B---------C----C


Wiring arrangement of new drayton SM2:

---------------------OFF--------ON
------------------HW--CH--HW--CH
--------L----N----1---2------3----4
-------AD--AB---C----------C----B
---------------------------------------------ie: as before yet with 1&4 changed
---------------------------------------------for new arrangement.

Even when changed to:

--------------------OFF--------ON
-----------------HW--CH---HW--CH
--------L----N----1----2-----3----4
-------AD--AB---C----B----C----B
---------------------------------------------ie: in line within wiring instructions
---------------------------------------------from new programmer.

The heating only works when selected on demand, not when on the once or twice timer option.

hope this can clarify things. thanxs