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OPERATIONAL AND CONNECTION INFORMATION
Rc/Rh Connections
For installations having a separate 24VAC transformer for heating and cooling, the
R connection can be separated into two connections, one for each transformer. This
allows isolation between the two transformers to be preserved. To separate Rc from
Rh, remove the factory supplied jumper between the Rc and Rh terminals. The Rh
terminal powers the W output. The Rc terminal powers the Y1, Y/Y2, G and O
outputs.
Wiring
For all wiring applications, use 22 AWG or larger wire. Continuous wire lengths
over 100 ft. (30.5 m) should use 20 AWG or larger. Wire lengths are not to exceed
250 ft. (76 m) per run.
O/B Terminal -- On HP Thermostat Only
This terminal is normally connected to the reversing valve of the heat pump. It is
called O when the valve is energized in cooling and B when it is energized in
heating. Option 10 of the Configuration Options makes the O/B selection.
Timers
There are several timers which influence the thermostat’s operation:
If any of the timers listed below is preventing the equipment from turning on, the
display icons which show the equipment is operating will be flashing to indicate a
turn--on delay is present.
Five--Minute Compressor Timeguard
This timer prevents the compressor from starting unless it has been off for 5
minutes. It can be defeated for one cycle by simultaneously pressing the FAN and
UP keys.