Whirlpool W2GH3, Installation Instructions Manual

Page: 7 / 12

7
Outdoor Unit Typical Wiring Diagram
Complete Installation
1. Operate the heat pump for a period of at least 15 minutes to
allow for pressures and temperatures to stabilize.
2. If heat pump does not appear to be functioning correctly,
have heat pump checked by a person certified by the EPA to
handle refrigerant.
Sequence of Operation
Cooling
Upon cooling demand, the thermostat closes circuit R to O and Y.
Closing R to O and Y energizes the reversing valve for cooling
operation and closes the heat pump contactor, starting the
compressor and outdoor fan. The thermostat automatically
closes R to G circuit, which also brings on the indoor fan at the
same time. Upon satisfying cooling demand, the thermostat will
open the above circuits and open the main contactor, stopping
the compressor and outdoor fan. If the indoor unit is equipped
with a delay timer, the blower will continue to operate for 60 –
90 seconds, which improves system efficiency.
Heating
Upon heating demand, the thermostat closes circuit R to Y, which
closes the heat pump contactor, starting the compressor and
outdoor fan. The reversing valve is not energized in the heating
mode. The thermostat again automatically brings on the indoor
fan at the same time. Upon satisfying heating demand, the
thermostat opens above circuits and stops heat pump operation.
Defrost Cycle
If the outdoor ambient conditions are such that frost forms on the
outdoor coil, the defrost control monitors the need for and
initiates and terminates defrost cycles as necessary to maintain
system performance.
The defrost control is time/temperature initiated and temperature
terminated with a maximum defrost time (time-out) of 10 minutes.
The time between defrost cycles is preset at 60-minute intervals
at the factory, but can be field adjusted between 30, 60, or
90 minutes. To adjust the time period between defrost cycles,
see “Adjust Time Between Defrost Cycles.”
The defrost control will initiate a defrost cycle when the selected
time period has elapsed and the defrost sensor sees a
temperature below freezing. At the start of a defrost cycle, the
defrost control will energize the reversing valve solenoid, shifting
the reversing valve and de-energizing the outdoor fan. The
defrost relay will also close, energizing temporary heat for
increased comfort during defrost (if the indoor unit is so
equipped). The heat pump will remain in defrost until the defrost
sensor has determined that the frost has been removed from the
coil or a 10-minute period has elapsed, whichever comes first.
BK
BK
R
Dual
Capacitor
Defrost Control
Thermostat
Line voltage - Field
Low voltage - Field
Line voltage - Factory
Low voltage - Factory
Ground
Thermostat
S87
Low
Pressure Switch
(if used)
BK
BK
BK
BK
PR
R
Y
Fan
OR
R
Reversing
Valve
Defrost
Thermostat
Ground
Lug
Equipment
Ground
PR
BK
BK
OR
R
Y
Compressor
Crankcase Heater
(if used)
Compressor
Contactor
Outdoor
Fan
BK
Low
Pressure Switch
(if used)
FAN
Fan
High
Pressure Switch
(if used)
High
Pressure
Switch
(if used)
Defrost Control
Reversing
Valve
D
efrost
Ther
m
ostat
Compressor
Contactor
Coil
Compressor
Crankcase
Thermostat
(if used)
Crankcase
Heater
(if used)
Compressor
Contactor
Defrost
Control
Dual
Capacitor
Outdoor
Fan
COMMON