Nordyne Two Stage R-410A Split System User's Information/Installation Instructions page 12

Miswired Module Indication
Green LED is not on,
module does not power up
Green LED intermittent,
module powers up only
when compressor runs
TRIP LED is on but system
and compressor check OK
TRIP LED and ALERT LED
flashing together
ALERT Flash Code 3
(Compressor Short Cycling)
displayed incorrectly
ALERT Flash Code 5, 6 or 7
(Open Circuit, Open Start Circuit
or Open Run Circuit) displayed
incorrectly
ALERT Flash Code 6 (Open
Start Circuit) displayed for Code 7 through the correct module sensing holes.
(Open Run Circuit) or vice versa
ALERT Flash Code 8
(Welded Contactor)
displayed incorrectly
Note: All units are shipped from the factory
with the default 70°F termination temperature
setting.
Defrost Test Procedure
1. Terminals "R"-"C" must have 18-30v present
between them in order for defrost sequences
to be initiated.
2 With heat mode thermostat demand ("Y" con-
nected to "R"), short (and hold) the "TEST"
pins together. This will energize reversing
valve to initiate a forced defrost. This will
bypass the ASCD and allow the high stage
compressor to come on immediately (if the
"REMOVE FOR NO DELAY" jumper at P6 is
removed). If the "REMOVE FOR NO DELAY"
jumper at P6 is installed, the compressor will
energize immediately following a 30-second
delay.
12
Recommended Troubleshooting Action
Determine if both R and C module terminals are
connected. Verify voltage is present at module's R and
C terminals. Review 24VAC Power W iring (page 4) for
R and C wiring.
Determine if R and Y terminals are wired in reverse.
Verify module's R and C terminals have a constant
source. Review 24VAC Power W iring (page 4) for R
and C wiring.
Verify Y terminal is connected to 24VAC at contactor
coil. Verify voltage at contactor coil falls below 0.5VAC
when off. Verify 24 VAC is present across Y and C when
thermostat demand signal is present. If not, R and C are
reverse wired.
Verify R and C terminals are supplied with 19-28VAC.
Verify Y terminal is connected to 24VAC at contactor coil.
Verify voltage at contactor coil falls below 0.5VAC when
off.
Check that compressor run and start wires are through
module's current sensing holes. Verify Y terminal is
connected to 24VAC at contactor coil. Verify voltage at
contactor coil falls below 0.5VAC when off.
Check that compressor run and start wires are routed
Determine if module's Y terminal is connected. Verify Y
terminal is connected to 24VAC at contactor coil. Verify
24VAC is present across Y and C when thermostat demand
signal is present. If not, R and C are reverse wired. V erify
voltage at contactor coil falls below 0.5VAC when off.
Review Thermostat Demand Wiring (page 4) for Y and C
wiring.
Table 3. Module Wiring Troubleshooting
3. next remove the short on the "TEST" pins. If
the Coil temperature is above the Terminate
Temperature selection setting, the defrost
cycle will be terminated (reversing valve
will de-energized). If the coil temperature is
below the Terminate Temperature election
setting, the defrost cycle will continue for 14
minutes (or until the coil temperature rises
above the Terminate Temperature selection
setting). Short the "TEST" pins for 1 second
or more to force the control out of defrost
and back to heating mode (reversing valve
de-energized). Compressor will come on im-
mediately (if the "REMOVE FOR NO DELAY"
jumper is removed). If the "REMOVE FOR NO
DELAY" jumper is installed, the compressor
will energize immediately following a 30-
second delay.