Troubleshooting - Bryant T6?PRH?A Installation Instructions Manual

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 Option 01 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
"−−" − If Thermidistat Control cannot properly read room temperature, display
will indicate "−−" and all outputs (except fan, if on) will turn off. In the case
where the installer has selected to average the local sensor and the remote room
sensor, the Thermidistat Control display will alternate between "−−" for the
failed sensor and the temperature sensed by the working sensor every 10
seconds. The control will operate from the temperature sensed by the working
sensor.
E1 − If the Display Module and the Equipment Control Module cannot
communicate via two−wire connection, an E1 will be displayed.
E2 − There is no E2 error message.
E3 − If Thermidistat Control cannot properly read outdoor temperature, and it is
needed for proper operation, display will indicate "−−" in the outdoor
temperature location. If Option 06, 08, 09, 22, 23 or 44 is not set to OFF, display
will indicate "−−" in the outdoor temperature location.
E4 − If Thermidistat Control's internal memory fails, E4 will be displayed.
Replace Thermidistat Control.
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