Hi gazdaz36, thank you for the reply. So the link between 3 & 4 on the boiler will result in d.8 reading 1 (active/demand) all the time? The RF connection is usually 8-10 when I check it - the 350f is close to the boiler anyway. There's no chance of the boiler being activated by another 350f...
My first post, sorry it's so long but I'm assuming more information is better?
My system:
EcoTEC Plus 428 (circa 2010)
Megaflo 300L storage tank
2 x 2 port zone valves
VR10 HW tank sensor
VR66 wiring centre set to mode 1
VRT350F Roomstat/timer
Earlier this year, with the assistance of an...