Robertshaw RS8110 Installation Manual page 11

Alternate Wiring (Conventional Systems)
If labels do not match letters on the thermostat, check the chart below and connect to terminal as shown
here (See notes, below).
Remove metal jumber if wires will be connected to both RH/R and RC terminals.
1
If a 24 volt common wire is present (typically labeled C or X) connect it to the C terminal. The C terminal is
2
not used if a 24 volt common wire is not present.
The O and B terminals are for a reversing valve (single stage heat pump application ONLY). These
3
terminals are not used on a system that is not a heat pump.
Place a jumper wire between the Y and W terminals if you have a single stage heat pump system ONLY.
4
WIRING
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