Carrier and Bryant Furnace Rapid flashing: Rapid flashing LED (reversed polarity)
Updated October 2026 · Sourced from Carrier and Bryant documentation
🛑 Turn it off and call a licensed pro
The control reports that the 115VAC line voltage polarity is reversed. The furnace will not run.
Is it safe to keep running? No. Turn it off and get it checked. Turn the furnace off at the breaker and call a licensed technician or electrician to correct the wiring polarity and ground.
Rapid flashing at a glance
| Code / how it shows | Meaning | Applies to |
|---|---|---|
| Rapid flashing Status LED flashes rapidly | Rapid flashing LED (reversed polarity) | Carrier 59SC5A single-stage 4-way multipoise condensing gas furnace (Series 1 and 2) |
🛑 Stop and call a licensed pro if
- Turn the furnace off at the breaker and call a licensed technician or electrician to correct the wiring polarity and ground.
- You smell gas. Leave the house, do not touch switches, and call your gas utility from outside.
- Flame rollout, limit or pressure switch codes that come back after one reset.
- Anything involving the control board, gas valve, flame sensor, igniter or venting.
- A carbon monoxide alarm sounds. Get everyone outside and call 911 or the fire department.
Safe first steps for any Carrier and Bryant code
- Count the LED flashes through the blower door window before you switch anything off. Cutting power can clear the code.
- Replace or clean the furnace air filter.
- Check the thermostat: correct mode, set above room temperature, and fresh batteries.
- Make sure the furnace power switch and breaker are on. If the furnace has locked out, turning the power off and back on once restarts it.
- Make sure the gas valve is in the ON position, following the lighting instructions on the furnace label only.
- On high-efficiency furnaces, look at the outside vent and intake pipes for snow, ice, leaves or nests (look only, do not take pipes apart).
Source: Carrier 59SC5A Installation, Start-up, Operating and Service and Maintenance Instructions, Fig. 62 Service Label, p.67. Codes are series-specific, so your unit's own manual is the final word. Reviewed October 2026.
Shaun Cain · Certified HVAC & Refrigeration Technician · Ask an HVAC technician
Related Carrier and Bryant codes
LED off : Status LED off (no power to control)LED on : Status LED steady on (normal)11 : No previous fault code stored12 : Blower on after power up13 : Limit circuit lockout14 : Ignition lockout21 : Gas heating lockout22 : Abnormal flame-proving signal23 : Pressure switch did not open24 : Secondary voltage fuse is open31 : Pressure switch did not close or reopened33 : Limit circuit fault (limit or rollout switch open)