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wiring diagram for Honewell thermostats model THE841R102?

replacing Lennox thermostat with Honeywell thermostat model T8411R. Need help with wiring
4 wires
G-green
O-orange
RH & RC, red spliced
W-white
Y-yellow, not from wall but from mercury adjusment


the Honeywell site has all diagrams.

but in short, excluding earth wire should only be 3. live, switch line, and poss neutral for temp accelerator

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