Current situation no timer but hardwired room thermostat. Previously had a hard wired timer/thermo but elec fitted current thermo only when the old one failed just to see me through the Summer. First image shows the boiler wiring and diagram. Second image the wiring diagram for wireless thermostat.
My understanding: I take a live feed from the upper block terminals 2 & 3 that connects to live/neutral on the receiver. (This wire comes from a fused spur on the other side of the wall) I then connect N/O & COM to the boiler upper block terminals 4 & 5. I remove the red wire link in 4 & 5.
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