Fiddled taking battery in and out for an hour (whilst watching TV), no joy - red light flashed for 6 or 7 seconds and RF601 appeared to switch from off to on and vice versa (but no function on override).
After about hour, when I put batteries in (exactly as I had done 30 to 40 times before)...
Vaillant EcoTEC 837 fitted jan 08 on a 3 year warranty offer. we had intermittant days when boiler didn't fire but fired is power cycled. Vaillant services 10m ago and replaced motor.
CH has been off in summer mode - CH won't go.
Drayton Digistat SCR Wireless (RF601) appears to send OK...