User's Manual

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See Wiring Diagrams for more information.
Temperature Offset After Power Cycle
To compensate for internal heat build--up from the electronics in the thermostat, the thermostat
will add an offset to the actual temperature that it measures. If the thermostat power is cycled
quickly, one can witness an immediate increase in the actual temperature displayed due to this
added offset. The thermostat display will return to the actual room temperature after several
minutes of operation.
TROUBLESHOOTING
If the display module doesn’t power up after power is applied, check the Rc/Rh and C terminals
for 24VAC. If 24VAC is present, check the voltage between Vg and V+. This voltage will be
approximately 12--20VDC. If voltage is present, check the polarity to make sure it is wired
correctly. The display will not power up if polarity is reversed.
If dashes appear for SW01 in config and during reboot, the problem could be the red pigtail
being wired to Rc or Rh and the black pigtail being wired to C. If so, remove the two--wire
pigtail and connect to the V+ and Vg terminals.
Error Codes
Comm Error -- If the Côr 7 Series Thermostat and the Two-Wire Relay Module cannot
communicate via two-wire connection, an Comm Error will be displayed.
HW Failure -- If Côr 7 Series Thermostat’s internal memory fails, HW Failure will be
displayed. Replace Thermostat.
Invalid HUM -- If Côr 7 Series Thermostat cannot properly read humidity, Invalid HUM will
be displayed. Replace Côr 7 Series Thermostat. If both Humidify and Dehumidify have been set
to OFF, the humidity value will be shown as “----” when viewed from the humidity menu, but no
Invalid HUM will be shown in the display.
Table 4 can be used as a troubleshooting tool for determining which outputs will be active for a
particular configuration and each operating mode. When replacing a failed component such as an
equipment control module or a display module, the installer should replace both parts as a
matched set. It is very easy to accidentally mix an A/C or HP display with a PRH equipment
control module. When this happens, some functions appear in the setup while others do not. This
can be very confusing to troubleshoot. Verify that both parts have the same model and serial
number when troubleshooting the thermostat.
Table 4 – Equipment Configuration Outputs
IDU
ODU
Equip
ment
Type
Options
Cool
Stage
1
Cool
Stage
2
Heat
Stage
1
Heat
Stage
2
Heat
Stage
3
Heat
Stag
e 4
EM
Heat
Stage
1
EM
Heat
Stage
2
1 Stage
1
Opt
--
Y/Y2
--
W/W1
--
--
--
--
--