Status Codes; Troubleshooting - Carrier 25HNA6 Installation Instruction

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
AMBER LED
OPERATION FAULT FLASH POSSIBLE CAUSE AND ACTION
CODE
On solid, no
Standby - no call for unit operation None flash Normal operation
Standard Thermo- Rapid, con- Unit being controlled by standard thermostat inputs instead of Infinity Con-
Emergency Mode - Model 25HNA9
stat Control tinuous flash- trol. Only high stage operation is available. This operating mode should be
only (25HNA9 only) ing used in emergency situations only.
Low Stage Cool/Heat Operation None 1, pause Normal operation
High Stage Cool/Heat Operation None 2, pause Normal operation
System Commu- 16 Communication with User Interface lost. Check wiring to UI, indoor and
nications Failure outdoor units
Control does not detect a model plug or detects an invalid model plug. Unit
Invalid Model Plug 25
will not operate without correct model plug.
High Pressure 31 * High-pressure switch trip. Check refrigerant charge, outdoor fan operation
Switch Open and coils for airflow restrictions.
Low Pressure
32* Low-pressure switch trip. Check refrigerant charge and indoor air flow.
Switch Open
Control Fault 45 Outdoor unit control board has failed. Control board needs to be replaced.
Line voltage < 187v for at least 4 seconds. Compressor and fan operation
Brown Out (230 v) 46
not allowed until voltage>__190v. Verify line voltage.
There is no 230v at the contactor when indoor unit is powered and cooling/
No 230v at Unit 47 heating demand exists. Verify the disconnect is closed and 230v wiring is
connected to the unit.
Outdoor Air Temp 53 Outdoor air sensor not reading or out of range. Ohm out sensor and check
Sensor Fault wiring.
Outdoor Coil Sen-
55 Coil sensor not reading or out of range. Ohm out sensor and check wiring.
sor Fault
Thermistors out of 56 Improper relationship between coil sensor and outdoor air sensor. Ohm out
range sensors and check wiring.
Low Stage Ther- Compressor operation detected then disappears while low stage demand
mal Cutout 71 * exists. Possible causes are internal compressor overload trip or start relay
and capacitor held in circuit too long (if installed).
High Stage Ther- Compressor operation detected then disappears while high stage demand
mal Cutout 72* exists. Possible causes are internal compressor overload trip or start relay
and capacitor held in circuit too long (if installed).
Contactor Shorted 73 Compressor voltage sensed when no demand for compressor operation
exists. Contactor may be stuck closed or there is a wiring error.
No 230V at Com-
pressor (25HNA9 74 Compressor voltage not sensed when compressor should be starting. Con-
Only) tactor may be stuck open or there is a wiring error.
Low Stage Did Not Specified start voltage at VR terminal was not achieved in low stage. Start
Start 75
(25HNA6 Only) relay was de-energized after 1 second.
Low Stage Did Not For 3 consecutive low stage starts, the specified start voltage at VR terminal
Start 3 times 76 was not achieved & start relay was de-energized. Low stage locked out for
(25HNA60nly) 30 minutes.
High Stage Did Not Specified start voltage at VS terminal was not achieved in high stage. Start
Start 77
(25HNA6 Only) relay was de-energized after 1 second.
High Stage Did Not For 3 consecutive high stage starts, the specified start voltage at VS terminal
Start 3 times 78 was not achieved & start relay was de-energized. High stage locked out for
(25HNA6 Only) 30 minutes.
Low Stage Ther- 81 Thermal cutout occurs in three consecutive low/high stage cycles. Low
mal Lockout stage locked out for 4 hours or until 24v power recycled.
High Stage Ther- 82 Thermal cutout occurs in three consecutive high/low stage cycles. High
mal Lockout stage locked out for 4 hours or until 24v power recycled.
Low-Pressure 83 Low pressure switch trip has occurred during 3 consecutive cycles. Unit
Lockout operation locked out for 4 hours or until 24v power recycled.
High-Pressure 84 High pressure switch trip has occurred during 3 consecutive cycles. Unit
Lockout operation locked out for 4 hours or until 24v power recycled.
Low Contactor
Open 85 Compressor voltage not sensed when compressor should be starting. Low
(25HNA6 Only) stage contactor may be stuck open or there is a wiring error.
High Contactor Compressor voltage not sensed when compressor should be starting. High
Open 87
(25HNA6 Only) stage contactor may be stuck open or there is a wiring error.
Sequence: Compressor contactor is de-energized and outdoor 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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