Carrier · Status code
Carrier 59SC6A status code 13: limit lockout or ignition lockout
Major code 13 covers two lockouts. Minor 13.1 means a switch in the main limit circuit stayed open for more than three minutes. Minor 13.2 means the ignition sequence failed four consecutive times. Both stop the burner until the cause is corrected.
Smell gas?
- Do not operate light switches, appliances or phones inside.
- Leave the building and leave the door open behind you.
- From outside, call the FortisBC emergency line at 1-800-663-9911 or 911.
- Only after that, call BC Wide about the furnace.
A furnace that will not run is a breakdown, not a gas emergency. Gas smell, a CO alarm, soot or scorching are.
On the control
- Code
- 13
- Minor
- 13.1 · 13.2
- Door LED
- 1 short flashes then 3 long
- Controller
- 59SC6A integrated furnace control with 3-digit LCD display and door LED
- Applies to
- Carrier Comfort 96 (59SC6A)
- Manual
- 59SC6A-01SI REV D
What each minor code says, verbatim
| Display | Manufacturer wording |
|---|---|
| 13.1 | Limit Lockout - switch open longer than 3 minutes in Main Limit circuit |
| 13.2 | Ignition Lockout after 4 consecutive ignition tries |
A code is a condition, not a diagnosis
A limit lockout (13.1) points at overheating in the airflow path or at the rollout side of the circuit responding to a combustion problem. An ignition lockout (13.2) means flame was never proven: gas supply, ignitor, flame sensing or combustion-air problems all produce it. Only on-site testing separates the causes.
Which furnaces this applies to
Documented for Carrier 59SC6A Comfort 96 furnaces in installation instructions 59SC6A-01SI REV D. The main limit circuit includes the manual-reset switch in the burner area that opens on flame rollout and must never be bypassed.
Scope: Carrier 59SC6A Comfort 96 furnaces with the on-board 3-digit display control. Not sure which control you have? Send us the full model number from the rating plate.
Safe things to look at first
- Read the full code on the control display through the door, including any minor digit (for example 33.2), and write it down.
- Look, without touching, for obvious conditions you can report: snow or ice at the vent terminations, water on the floor, a loaded filter, a condensate pump that is full or off.
- Note whether the furnace still heats at all, and how long it runs before the code returns.
- For 13.1 check whether the blower runs and whether the filter is loaded; for 13.2 confirm the gas shut-off valve is on and the inducer runs before the code appears.
- If you smell gas at any point, leave the building and call FortisBC at 1-800-663-9911 or 911 first.
Do not
- Do not bypass or jumper the door switch, limit switches, rollout switches or pressure switches.
- Do not open the burner compartment, disconnect tubing, or adjust the gas valve or gas pressure.
- Do not keep cycling power to force the furnace to relight; repeated resets hide the fault and can allow unburned gas to build up after ignition failures. If the code returns, stop and call.
What a technician does
- A technician measures temperature rise and static pressure, checks the filter, blower and duct path, and verifies every switch in the main limit circuit before resetting.
- For an ignition lockout the gas supply, hot-surface ignitor, flame-signal and venting are checked before the fault history is cleared.
Related components and symptoms
Questions people ask
Can I reset a 13 lockout myself?
The control retries when conditions clear, but repeated resetting is exactly what Carrier's manual warns against. The cause must be found; a limit circuit that stays open is the furnace protecting itself.
Does code 13 mean the heat exchanger failed?
Not by itself. Limit lockouts usually trace to airflow and ignition lockouts to the ignition sequence. A technician tests before any part is replaced.
Seeing code 13 on your Carrier?
Tell us the full code, the model number and whether the furnace still heats on low. BC Wide prioritizes no-heat calls across Greater Vancouver.