Installation guide

Status Codes
Table 6 shows the status codes flashed by the amber status light.
Most system problems can be diagnosed by reading the status code
as flashed by the amber status light on the control board.
The codes are flashed by a series of short and long flashes of the
status light. The short flashes indicate the first digit in the status
code, followed by long flashes indicating the second digit of the
error code.
The short flash is 0.25 seconds ON and the long flash is 1.0 second
ON. Time between flashes is 0.25 seconds, Time between short
flash and first long flash is 1.0 second, Time between code
repeating is 2.5 seconds with LED OFF.
EXAMPLE:
3 short flashes followed by 2 long flashes indicates a 32 code.
Table 6 shows this to be low pressure switch open.
Table 6 - TROUBLESHOOTING
OPERATION
Standby - no call for unit operation
Low Stage Cool/Heat Operation
High Stage Cool/Heat Operation
Sequence: Compressor contactor is
FAULT
None
None
None
System Commu-
nications Failure
Invalid Model Plug
High Pressure
Switch Open
Low Pressure
Switch Open
Control Fault
Brown Out (230 v)
No 230v at Unit
Outdoor Air Temp
Sensor Fault
Outdoor Coil
Sensor Fault
Thermistors out of
range
Low Stage
Thermal Cutout
High Stage
Thermal Cutout
Contactor Shorted
No 230V at
Compressor
(25HNA9 Only)
Low Stage Did Not
Start
(25HNA6 Only)
Low Stage Did Not
Start 3 times
(25HNA60nly)
High Stage Did Not
Start
(25HNA6 Only)
High Stage Did Not
Start 3 times
(25HNA6 Only)
Low Stage
Thermal Lockout
High Stage
Thermal Lockout
Low- Pressu re
Lockout
High-Pressure
Lockout
Low Contactor
Open
(25HNA6 Only)
High Contactor
Open
(25HNA6 Only)
_e-energized and out(
AMBER LED
FLASH
CODE
On solid, no
flash
1, pause
2, pause
16
25
31"
32*
45
46
47
53
55
56
71"
72*
73
74
75
76
77
78
81
82
83
84
85
POSSIBLE CAUSE AND ACTION
Normal operation
Normal operation
Normal operation
Communication with User Interface lost. Check wiring to UI, indoor and
outdoor units
Control does not detect a model plug or detects an invalid model plug. Unit
will not operate without correct model plug.
High-pressure switch trip. Check refrigerant charge, outdoor fan operation
and coils for airflow restrictions.
Low-pressure switch trip. Check refrigerant charge and indoor air flow.
Outdoor unit control board has failed. Control board needs to be replaced.
Line voltage < 187v for at least 4 seconds. Compressor and fan operation
not allowed until voltage>__190v. Verify line voltage.
There is no 230v at the contactor when indoor unit is powered and cooling/
heating demand exists. Verify the disconnect is closed and 230v wiring is
connected to the unit.
Outdoor air sensor not reading or out of range. Ohm out sensor and check
wiring.
Coil sensor not reading or out of range. Ohm out sensor and check wiring.
Improper relationship between coil sensor and outdoor air sensor. Ohm out
sensors and check wiring.
Compressor operation detected then disappears while low stage demand
exists. Possible causes are internal compressor overload trip or start relay
and capacitor held in circuit too long (if installed).
Compressor operation detected then disappears while high stage demand
exists. Possible causes are internal compressor overload trip or start relay
and capacitor held in circuit too long (if installed).
Compressor voltage sensed when no demand for compressor operation
exists. Contactor may be stuck closed or there is a wiring error.
Compressor voltage not sensed when compressor should be starting. Con-
tactor may be stuck open or there is a wiring error.
Specified start voltage at VR terminal was not achieved in low stage. Start
relay was de-energized after 1 second.
For 3 consecutive low stage starts, the specified start voltage at VR terminal
was not achieved & start relay was de-energized. Low stage locked out for
30 minutes.
Specified start voltage at VS terminal was not achieved in high stage. Start
relay was de-energized after 1 second.
For 3 consecutive high stage starts, the specified start voltage at VS terminal
was not achieved & start relay was de-energized. High stage locked out for
30 minutes.
Thermal cutout occurs in three consecutive low/high stage cycles. Low
stage locked out for 4 hours or until 24v power recycled.
Thermal cutout occurs in three consecutive high/low stage cycles. High
stage locked out for 4 hours or until 24v power recycled.
Low pressure switch trip has occurred during 3 consecutive cycles. Unit
operation locked out for 4 hours or until 24v power recycled.
High pressure switch trip has occurred during 3 consecutive cycles. Unit
operation locked out for 4 hours or until 24v power recycled.
Compressor voltage not sensed when compressor should be starting. Low
stage contactor may be stuck open or there is a wiring error.
87 Compressor voltage not sensed when compressor should be starting. High
stage contactor may be stuck open or there is a wiring error.
oct fan is energized for up to 15 minutes. If demand still exists, control will energize compressor
contactor after 15 minute delay, If fault is cleared, unit will resume operation. If fault still exists, fan shuts off, and error code continues to flash. Control will
attempt re-start every 15 minutes. Cycling low voltage defeats the 15 minute delay.
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