Outdoor Thermostat (If Supplied); Defrost Cycle Timer; Defrost Test Procedure; Module Wiring Troubleshooting - Nordyne R-410A Installation Instructions Manual

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
for any unusual noises. If present, locate and
determine the source of the noise and correct
as necessary.

OUTDOOR THERMOSTAT (if supplied)

The outdoor thermostat prevents the electrical
auxiliary heat (if used) from operating above a
desired set point. Selection of the set point is
determined from the building design heat load.
The thermostat is adjustable from 45°F to 0°F.
The factory temperature setting is at 40°F.
Defrost Cycle Timer — The defrost cycle timer
controls the time interval of the hot gas defrost
after the defrost sensor closes. It is located
in the lower left corner of the defrost control
board. Three interval settings are available: 30
minutes, 60 minutes, and 90 minutes. Time setting
selection is dependent on the climate where the
unit is being installed.
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 2. Module Wiring Troubleshooting
To set the cycle timer, place the timing pin on
the defrost control board to the desired time
interval post.
Note: All units are shipped from the factory with
the default time setting of 30 minutes. Maximum
heating performance can be achieved by setting
the time to 90 minutes.

Defrost Test Procedure

1.
Example 1. Dry climate of Southern
Arizona. A 90 minute setting is
recommended.
Example 2. Moist climate of Seattle,
Washington. A 30 minute setting is
recommended.
Terminals "R"-"C" must have 18-30v present
between them in order for time delay and
defrost sequences to be initiated.
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