13
Table 2. Module Wiring Troubleshooting
3. Defrost board speed-up. With compressor
running in heat mode, next jump the “Test”
pin to “C” on terminal strip. This will initiate
a defrost test in 5, 10 or 15 seconds (This
is determined by the 30, 60 or 90 minute
defrost pin settings. The factory setting will
be 30 minutes). Note that this will bypass the
compressor off delay when the unit goes into
defrost test and if left in defrost test, the delay
will be bypassed when the test is terminated
by the processor. If the jumper is removed
before the test is over the processor will
perform the remainder of a normal defrost.
See step 2 above.
4. Remove the jumpers.
Note: The delay/no-delay pin concerns compressor
operation during defrosts. The default setting is
delay. Reciprocating compressors should only
use this setting in conjunction with an approved
hard start kit. Scroll compressors that have noise
issues while going into or coming out of defrost
should use this 30 second delay to reduce the
defrost noise. To switch from no-delay to delay
remove the pin from the “no-delay” pin location
and shift it to the “delay” pin location.
Speed up changes:
Manually initiating a defrost will cause the
compressor to run continually when entering
defrost.
Normal defrost operation:
To test normal defrost operation when the
temperature is above 35°F, jumper “R” to
“DFT” on the 624656 board and allow the unit
to run for 30 minutes. Defrost will continue
until the “R” to “DFT” jumper is removed or
for 10 minutes. Remove the jumper.
The 5 minute time delay feature can be shortened
1 time to 1 second by jumping the “Test” to “C”
terminal. Remove the jumper and repeat as
desired.
Note: If jumper is left on the “Test” to “common”
pins permanently, the defrost cycle will become
inoperable.
Miswired Module Indication
Recommended Troubleshooting Action
Green LED is not on, module does not power up
• Determine if both
R & C module terminals are connected.
• Verify voltage is present at module’s
R & C terminals.
Green LED intermittent, module powers up only when
compressor runs
• Determine if
R & Y terminals are wired in reverse.
• Verify modules R & C terminals have a constant source.
Trip LED is on, but system and compressor check OK
• Verify
Y terminal is connected to 24VAC at contactor coil.
• Verify voltage at contactor coil falls below 0.5VAC when off.
• Verify 24VAC is present across
Y & C when thermostat demand
signal is preset. If not, R & C are reversed wired.
TRIP LED & ALERT LED flashing together
• Verify
R & C terminals are supplied with 19 - 28VAC.
ALERT Flash CODE 3 displayed incorrectly
(Compressor short cycling)
• Verify
Y terminal is connected to 24VAC at contactor coil.
• Verify voltage at contactor coil falls below 0.5VAC when off.
ALERT Flash Code 5, 6, or 7 displayed incorrectly
(Open Circuit, Open Start Circuit or Open Run
Circuit)
• Verify the compressor run and start wires are routed through the
module’s current sensing holes.
• Verify the
Y terminal is connected to 24VAC at contactor coil.
• Verify voltage at contactor coil falls below 0.5VAC when off.
ALERT Flash Code 6 (Open Start Circuit) displayed
for Code 7 (Open Run Circuit) or vice-versa
• Verify the compressor run and start wires are routed through the
correct module sensing holes.
ALERT Flash Code 8 displayed incorrectly (Welded
Contactor)
• Determine if module’s
Y terminal is connected.
• Verify
Y terminal is connected to 24VAC at contactor coil.
• Verify 24VAC is present across
Y & C when thermostat demand
signal is present. If not, R & C are reversed wired.
• Verify voltage at contactor coil falls below 0.5VAC when off.
• Review Thermostat Demand Wiring (page 10) for
Y & C wiring.
