506257-01
Issue 1330
Page 22 of 29
Thermostat Demand Wiring
The diagnostic module requires a thermostat demand signal
to operate properly. The thermostat demand signal input,
labeled Y on the module, should always be connected
to the compressor contactor coil so that when the coil is
energized, the demand signal input is 24VAC. When the
coil is not energized, the demand signal input should be
less than 0.5VAC.
Miswired Module Codes
Depending on the system configuration, some ALERT flash
codes may not be active. The presence of safety switches
affects how the system alerts are displayed by the module.
Miswiring the diagnostic nodule will cause false LED codes.
Table 12 Describes LED operation when the module is
miswired and what troubleshooting action is required to
correct the problem.
Miswired Module Troubleshooting
Table 12
