Terminal Designations - Honeywell Wi-Fi Thermostat 9000 Installation Manual

Wiring
Terminal
release
Remove
jumper loop
ONLY if you
have both R
and RC wires.

Terminal Designations

Common wire from secondary side of cooling transformer (in case of two transformers)
C
Optional wire save module.
K
Cooling power. Connect to secondary side of cooling system transformer.
Rc
Heating power. Connect to secondary side of heating system transformer.
R
1st stage heat relay. Or changeover valve for heat pumps.
W-O/B
1st stage compressor contactor.
Y
Fan relay.
G
2nd stage heat relay. Or heat pump auxiliary/Emergency heat relay.
W2-Aux/E
2nd stage compressor contactor.
Y2
Heat pump system monitor.
L
Jumper Loop - a plug with a wire loop used to connect the R to the RC terminals, Leave jumper loop
in place in single transformer systems. Remove (unplug) jumper loop in the two transformer systems.
3
Terminal
holes accept
one wire
33-00235