The underfloor heating in my conservatory runs of my main heating system and the thermostat merely switches the separate pump on. It only has 2 wires to connect. I am replacing a Danfoss TP 5000 with a Danfoss 5000RF with an RX1 receiver (so that it is wireless) they have different back plates. The original one was wired with the brown wire going to C N/O and the black wire going to B COM. The new backplate has a choice of N - L - 1 - 2(COM) - 3 ON - 4 OFF. I cant seem to get any life out of it whatever combination I try although I haven't tried too many for fear of damaging something. Hopefully there is a simple solution, Any help appreciated.