Carrier/Bryant AC Fault Codes Explained
Carrier and Bryant air conditioners — both part of the same product family — use similar fault code systems across their residential lines. Whether you own a Carrier Infinity 21, Performance 17, or Bryant Evolution Extreme, understanding what your system's fault codes mean can help you respond appropriately and avoid costly compressor damage from running a malfunctioning system. This guide covers the most common Carrier and Bryant AC fault codes, their causes, and your best course of action.
Where Codes Appear on Carrier/Bryant AC Systems
On standard Carrier and Bryant split-system air conditioners, a LED status light on the outdoor unit control board blinks a fault code. Infinity and Evolution systems with a communicating thermostat (Infinity Touch Control or Evolution Connex) display fault codes on-screen and log them with timestamps. These communicating systems can also send diagnostic data through the Carrier Home app when Wi-Fi connected.
Common Carrier/Bryant AC Fault Codes
| Code | Meaning | What to Do |
|---|---|---|
| 1 flash | System lockout after repeated faults | One reset; call if returns |
| 2 flashes | High-pressure lockout | Check condenser airflow; call tech |
| 3 flashes | Low-pressure lockout | Technician required — refrigerant charge |
| 4 flashes | Compressor fault — overload or high temperature | Technician required |
| Fault 13 | Loss of charge — low refrigerant detected | Technician required — check for leak |
| Fault 17 | Inverter fault (variable-speed models) | Technician required — inverter board |
| Fault 22 | Outdoor unit communication fault | Check wiring; technician if wiring OK |
| Fault 31 | Low voltage at outdoor unit | Check circuit breaker; call electrician if recurring |
| Fault 33 | Condenser fan motor fault | Technician required — fan motor or capacitor |
| Fault 45 | Control board fault | Technician required — board replacement |
Inverter Faults on Variable-Speed Models
Carrier Infinity and Bryant Evolution variable-speed (Greenspeed) compressors use an inverter drive to vary compressor speed. Inverter faults (e.g., Fault 17) are among the more complex issues these systems can develop. They can be caused by high ambient temperatures, voltage irregularities, or inverter board failures. These faults require a technician with inverter training and, in some cases, factory technical support. Do not attempt multiple resets — inverter faults that recur indicate a genuine hardware problem that resets cannot fix.
What Homeowners Can Check
Condenser coil and fan: Inspect the outdoor unit for debris blocking airflow. Standing leaves, grass clippings, or cottonwood can clog the coil fins. Gently spray the coil fins from inside-out with a garden hose to clean them. Never use a pressure washer — it bends the fins.
Air filter: Replace the indoor air filter. A clogged filter reduces evaporator airflow, causing ice buildup and low-pressure faults.
Circuit breaker and disconnect: If the outdoor unit won't start, check the main panel breaker and the fused disconnect box mounted near the condenser. Replace blown fuses with the correct amperage only.
Thermostat wiring: On communicating systems, a broken or pinched thermostat cable can cause communication faults. Inspect the cable for visible damage, particularly where it passes through walls or chases.
When to Call a Professional
Low-pressure and loss-of-charge faults indicate a refrigerant issue that only a licensed technician can address. Running the system with low refrigerant damages the compressor rapidly. Inverter faults, compressor faults, and fan motor faults all require professional diagnosis and parts replacement.
Burkhardt Heating, Cooling, Plumbing & Electric has been repairing Carrier and Bryant systems across Southeastern Wisconsin for over 60 years. Our NATE-certified technicians carry common AC parts on every service vehicle and provide 24/7 emergency service during peak cooling season.
Carrier/Bryant AC Repair in Wisconsin
Don't ignore fault codes during the summer. A system that trips once and resets may be signaling a developing problem that, left unaddressed, becomes a compressor failure at the worst possible time.
If you see any of these codes, call Burkhardt at 414-206-3049. Our NATE-certified technicians can diagnose and repair the issue — usually in a single visit.
Ready to schedule service? Call Burkhardt Heating, Cooling, Plumbing & Electric at 414-206-3049 or contact us online. Available 24/7 for emergencies.
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