PS4000/PS5000 Touchscreen Programmable Thermostat
BALANCE
POINT
OUT
D
OO
R
TEMP
E
R
ATUR
E
COMPRESSOR ONLY
FOSSIL FUEL ONLY
Figure 32. Dual Fuel Heat Pump Operation
in Heat mode with Balance Point Set.
87
1. Choose correct heat pump application
in Installer Set-up Number 0170.
2. Choose
Fossil Fuel Option
as the
back-up heat source in Installer Set-up
Number 0200.
3. Choose
No External Fossil Fuel Kit
Option
to control the back-up heat in
Installer Set-up Number 0210.
4. Choose
Outdoor Temperature Sensor
for Heat Pump Temperature Lockouts
Option
in Installer Set-up Number 0340.
5. Choose appropriate
Balance Point
Temperature
in Installer Set-up Number
0350.
OPERATION IN HEAT MODE ABOVE BALANCE
POINT (OUTDOOR TEMPERATURE)
When the outdoor temperature is above
PS5000 ONLY:
the selected Balance Point Temperature
(ISU 0350), only the compressor operates
and the fan (G terminal) energizes when
the thermostat calls for heat. See Figure 32.
OPERATION IN HEAT MODE BELOW
BALANCE POINT (OUTDOOR TEMPERATURE)
When the outdoor temperature is below
PS5000 ONLY:
the selected Balance Point Temperature
(ISU 0350), only the Fossil Fuel (auxiliary
heat) operates and the fan (G terminal)
does not energize when the thermostat
calls for heat.
