20
T500 Series Programmable Thermostats Product/Technical Bulletin
S
etting Electronic Outdoor High and
Low Temperature Balance Points
(T500HPP-1 only)
The optional outdoor temperature sensor (order
separately) can be installed to allow the selection of
outdoor balance points that will lock out auxiliary heat
or cooling, depending on the outdoor temperature.
The factory-set HibP (auxiliary heat) and LobP
(compressors) setpoints are 48
°
C (118.4
°
F), and
-48
°
C (-54.4
°
F) respectively. The HibP and/or LobP will
be shown on lower LCD.
The HibP is the temperature above which the auxiliary
heat is locked out. The LobP is the temperature below
which the compressors are locked out.
To set the balance points:
1. Press and hold the
Outdoor
button while pressing
the
Mode
button.
HibP
will appear on the display.
2. Raise or lower the HibP (high balance point) by
pressing the
∨∨∨∨
or
∧∧∧∧
buttons.
3. Set the LobP (low balance point) by pressing and
holding the
Outdoor button. LobP
will appear on
the display.
4. Raise or lower the LobP by pressing the
∨∨∨∨
or
∧∧∧∧
buttons to set the auxiliary heat setpoint.
5. Press
Resume
to return to the normal display.
O
ptions
Remote Sensor
The indoor remote sensor allows the T500 to be
mounted away from the controlled space, and allows
use of multiple sensors for temperature averaging.
Order separately. See
Table 10: Optional Accessories.
Outdoor Sensor
Order separately. See
Table 10: Optional Accessories.
P
ower Failures
If power fails, AC will be displayed for 2 hours. After
2 hours, the display will go blank.
If power is restored in the first 2 hours, the internal
clock will be current and the thermostat will resume
normal operation. If power is restored after 2 hours,
12:00 AM will flash and the thermostat will control to
the night event setpoint until the clock is reset.
Note:
If the power fails when the thermostat is in the
continuous HOLD mode, the thermostat will
continue controlling to the HOLD temperature
when power is restored. When the user
presses the
Resume
button, the clock will
flash 12:00 AM and will remain in the night
event setpoint until the clock is reset.
V
erification
To verify proper functioning of the thermostat:
1. Press
the
Mode
button to select the heat or cool
mode. (See Figure 24.)
2. Press
the
∨∨∨∨
or
∧∧∧∧
buttons to raise the setpoint
above or below the current ambient temperature.
The thermostat should call for either heating or
cooling.
If the equipment does not come on, proceed to the
Troubleshooting
section.
Mode
Clock
Set Temp
Outdoor
Fan
Program
Resume
Hold
66
5:00
Mo
AM
Press to
select mode
(heat or cool).
Figure 24: Verifying Proper Operation
Sensor Calibration (Fan/10 Seconds)
The internal and remote sensors can be calibrated to
eliminate wire resistance errors or to match another
reference.
1. Press and hold the
Fan
button for 10 seconds.
2. Adjust the temperature with the
∨∨∨∨
or
∧∧∧∧
buttons.
The temperature is shown on the lower display to
the hundredths place. For example, 72
°
F on the
large display is shown as 72 13.
