We may have found other answers which could help you.
Click here for Heating Will Not ComeDrayton Digistat +RF Model RF-601?
Drayton sm2 timeswitch?
how to replace batteries in my Drayton Digistat RF1?
is it possible to repair a non digital Drayton SM2 timer?
drayton digistatrf1 wireless system?
Drayton Digistat+2 RF?