506257-01
Issue 1330
Page 21 of 29
Every time the module powers up, the last ALERT LED
flash code that occurred prior to shutdown is displayed for
60 seconds. The module will continue to display the
previous flash code until the condition returns to normal or
21VAC is removed from the module. TRIP and ALERT LEDs
flashing at the same time means control circuit voltage is
too low for operation.
24VAC Power Wiring
The diagnostic module requires a constant nominal 24VAC
power supply. The wiring to the module’s R and C terminals
must be directly from the indoor unit or thermostat. The
module cannot be powered by R and C terminals on the
defrost board without experiencing nuisance alerts.
Flash Codes (cont.)
Table 11
