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.
Codes Table
Flash Code | Possible Cause |
---|---|
On solid, no flash | Normal operation |
Rapid continuous flashing | Unit being controlled by standart thermostat inputs instead of Evolution Control. Only high stage operation is aveliable. This operating mode should be used in emergency situations only |
1 pause | Normal operation |
2 pause | Normal operation |
16 | Communication with User Interface lost. Check wiring to UI, indoor and outdoor units |
25 | Control does not detect a model plug or detects an invalid model plug. Unit will not operate without correct model plug |
31 | High - pressure switch trip. Check refrigerant charge, outdoor fan operating and coils for airflow restrictions |
32 | Low - pressure switch trip. Check refrigerant charge and indoor air flow. |
45 | Outdoor unit control board has failed. Control board needs to be replaced. |
46 | Line voltage < 187v for at least 4 seconds. |
47 | There is no 230v at the contactor when indoor unit is powered and cooling/heating demand exists. |
53 | Outdoor air sensor not reading or out of range. |
55 | Coil sensor not reading or out of range. Ohm out sensor and check wiring. |
56 | Improper relationship between coil sensor and outdoor air sensor. Ohm out sensor and check wiring. |
71 | 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 |
72 | 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 |
73 | Compressor voltage sensed when no demand for compressor operation exists. Contactor may be stuck closed or there is a wiring error |
74 | Compressor voltage not sensed when compressor should be starting. Contactor may be stuck open or there is a wiring error |
75 | Specified start voltage at VR terminal was not achieved in low stage. Start relay was de-energized after 1 second |
76 | For 3 consecutive low stage starts, the specified start voltage at VR terminal was not achieved and start relay was de-energized. Low stage locked out for 30 minutes. |
77 | Specified start voltage at VS terminal was not achieved in high stage. Start relay was de-energized after 1 second |
78 | For 3 consecutive high stage starts, the specified start voltage at VS terminal was not achieved and start relay was de-energized. High stage locked out for 30 minutes |
81 | Thermal cutout occurs in three consecutive low/high stage cycles. Low stage locked out 4 hours or until 24v power recycled |
Heat Pumps Codes
A Note About Safety: Any time you see this symbol in manuals, instructions and on the unit, be aware of the potential for personal injury. There are three levels of precaution: Danger identifies the most serious hazards which will result in severe personal injury or death. Warning signifies hazards that could result in personal injury or death. Caution is used to identify unsafe practices which would result in minor personal injury or product and property damage. Note is used to highlight suggestions which will result in enhanced installation, reliability, or operation.
Personal injury, death and / or property damage hazard, Failure to follow this warning could result in personal injury, death or property damage. Improper installation, adjustment, alteration, service, maintenance, or use can cause explosion, fire, electrical shock, or other conditions which may cause personal injury or property damage. Consult a qualified installer, service agency, or your distributor or branch for information or assistance. The qualified installer or service agency must use factory – authorized kits or accessories when modifying this product. Read and follow all instructions and warnings, including labels shipped with or attached to unit before operating your new air conditioner.
Electrical shock hazard, Failure to follow this warning could result in personal injury or death. Disconnect all electrical power to the indoor air handler or furnace before removing access panels to perform any maintenance. Disconnect power to both the indoor and outdoor units.
Troubleshooting
Fault | Possible Cause |
---|---|
System Communications Failure | Communication with User Interface lost. Check wiring to User Interface, indoor and outdoor units |
Invalid Model Plug | Control does not detect a model plug or detects an invalid model plug. Unit will not operate without correct model plug |
High Pressure Switch Open | High pressure switch trip. Check refrigerant charge, outdoor fan operation and coils for airflow restrictions |
Low Pressure Switch or Discharge Temp Switch Open | Low pressure switch or discharge temperature switch trip. Check refrigerant charge and indoor air flow. |
Control Fault | Outdoor unit control board has failed. Control board needs to be replaced. |
Outdoor Air Temp Sensor Fault | Outdoor air sensor not reading or out of range. Ohm out sensor and check wiring |
Outdoor Coil Sensor Fault | Coil sensor not reading or out of range. Ohm out sensor and check wiring |
Thermistors out of range | Improper relationship between coil sensor and outdoor air sensor. Ohm out sensors and check wiring |
Low Stage Thermal Cutout | 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 |
High Stage Thermal Cut out | 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 |
Low Stage Thermal Lock out | Thermal cutout occurs in three consecutive low/high stage cycles. Low stage locked out for 4 hours or until 24v power recycled |
Manual
Bryant Air Conditioners Heat Pumps Manual PDF
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