What causes Carrier Gas Furnace 14?

Gas turned off at the manual shut-off valve or the gas valve's own on/off switch. Low inlet gas pressure, or low manifold pressure. Oxide build-up on the flame sensor, so the control can't detect the flame (Carrier lists 0.5 microamps DC minimum, 4.0 to 6.0 typical). A flame sensor that is grounded, out of position, or a damaged electrode. The green/yellow ground wire not connected to the furnace sheet metal, or poor control ground continuity. A failed hot surface igniter, or a broken igniter wire or harness. A gas valve that doesn't open, opens slowly, or isn't getting 24 volts because of a loose wire. Inadequate flame carry-over or rough ignition across the burners. On variable-speed models with the inducer at full speed during lockout: flame rollout lifting the flame off the sensor. A faulty furnace control board, once everything else checks out.

How do I fix Carrier Gas Furnace 14?

Confirm the code: look through the sight glass on the blower door and count 1 short flash followed by 4 long flashes. Write it down before you cut power. Make sure the gas is on: check the manual gas shut-off valve on the pipe to the furnace (handle in line with the pipe) and the on/off switch or knob on the gas valve. If other gas appliances aren't working either, call your gas utility. Check the furnace filter and replace it if it's dirty; while you have the panel off, look for any obvious disconnected wires around the burner area without touching anything inside the control compartment. Carrier's controls retry on their own after 3 hours. If the furnace locks out again with code 14, or you see code 34 flashing, the cause still needs fixing. If you're comfortable doing it with the power and gas off, a technician-style fix Carrier lists is cleaning the flame sensor rod with fine sandpaper or fine steel wool to remove oxide build-up. If you're not sure which part is the sensor, leave it for a pro. If you smell gas at any point, don't try to relight or reset anything: leave the house and call your gas utility or 911 from outside.

When should I call a pro for Carrier Gas Furnace 14?

Running Carrier's component test to see whether the hot surface igniter glows orange/white hot within the 15-second warm-up, then checking for 115 VAC at the igniter connector and continuity through the harness and igniter. Checking for 24 VAC at the gas valve on a call for heat, continuity of the gas valve wires back to the control, and whether the valve actually opens (gas should flow at full pressure within 4 seconds). Measuring flame current with a DC microammeter in series with the flame sensor wire; below 0.5 microamps means cleaning, repositioning or replacing the sensor electrode. Checking inlet and manifold gas pressure, firing rate, burner carry-over and air leakage around the igniter bracket. On variable-speed models where the inducer stays at full speed during lockout, investigating flame rollout as Carrier's 58-06T guide describes. Replacing the furnace control only after the igniter, gas valve, flame sensor and gas supply all check out, as Carrier's troubleshooting steps direct.

Code: 14🔥 Carrier Gas Furnace

Carrier Furnace Code 14: Ignition Lockout (Meaning, Causes, Fixes)

Q: What does Carrier Gas Furnace 14 mean?

Status code 14 on a Carrier furnace (1 short flash, then 4 long flashes) is Ignition Lockout: the furnace tried to light the burners and prove flame four times and failed every time, so it stopped trying. Carrier's controls auto-reset after 3 hours and try again. Code 14 is the end result of repeated code 34 (Ignition-Proving Fault), so the real causes are the same: gas turned off or low gas pressure, a dirty or grounded flame sensor, a failed hot surface igniter, a gas valve problem, or a loose ground wire. Carrier status codes are two-digit numbers where the first digit is the number of short flashes and the second the number of long flashes, so code 14 is 1 short flash followed by 4 long flashes. Carrier's troubleshooting guides for its 2-stage furnaces (58-3T) and variable-speed furnaces (58-06T) define it the same way: "IGNITION LOCKOUT - This status code indicates the furnace failed to ignite gas and/or prove flame in 4 attempts," and the control will auto-reset in 3 hours. Each failed attempt is a code 34 (Ignition-Proving Fault, meaning flame was not sensed during the trial for ignition); the control repeats the ignition sequence 3 more times before it locks out with code 14, so Carrier sends you to the code 34 checks to find the cause. On variable-speed models, 58-06T adds that if the inducer is running at full speed during the lockout, flame sense was lost 3 times within 60 minutes of gas valve run time after the valve had already been on for 70 seconds, which is usually caused by flame rollout making the flame lose contact with the sensor before the rollout switch trips. Newer Carrier furnaces with three-digit codes split this into 14.1 (Ignition Lockout, 4 failed attempts), 14.2 and 14.3 (Flame Lost Lockout), and point to the 34 codes plus manifold pressure, firing rate and inlet gas pressure swings.

Reviewed 2026-10-23 · Based on 6 manufacturer & service sources

What the code means

Carrier status codes are two-digit numbers where the first digit is the number of short flashes and the second the number of long flashes, so code 14 is 1 short flash followed by 4 long flashes. Carrier's troubleshooting guides for its 2-stage furnaces (58-3T) and variable-speed furnaces (58-06T) define it the same way: "IGNITION LOCKOUT - This status code indicates the furnace failed to ignite gas and/or prove flame in 4 attempts," and the control will auto-reset in 3 hours. Each failed attempt is a code 34 (Ignition-Proving Fault, meaning flame was not sensed during the trial for ignition); the control repeats the ignition sequence 3 more times before it locks out with code 14, so Carrier sends you to the code 34 checks to find the cause. On variable-speed models, 58-06T adds that if the inducer is running at full speed during the lockout, flame sense was lost 3 times within 60 minutes of gas valve run time after the valve had already been on for 70 seconds, which is usually caused by flame rollout making the flame lose contact with the sensor before the rollout switch trips. Newer Carrier furnaces with three-digit codes split this into 14.1 (Ignition Lockout, 4 failed attempts), 14.2 and 14.3 (Flame Lost Lockout), and point to the 34 codes plus manifold pressure, firing rate and inlet gas pressure swings.

Likely causes

Gas turned off at the manual shut-off valve or the gas valve's own on/off switch
Low inlet gas pressure, or low manifold pressure
Oxide build-up on the flame sensor, so the control can't detect the flame (Carrier lists 0.5 microamps DC minimum, 4.0 to 6.0 typical)
A flame sensor that is grounded, out of position, or a damaged electrode
The green/yellow ground wire not connected to the furnace sheet metal, or poor control ground continuity
A failed hot surface igniter, or a broken igniter wire or harness
A gas valve that doesn't open, opens slowly, or isn't getting 24 volts because of a loose wire
Inadequate flame carry-over or rough ignition across the burners
On variable-speed models with the inducer at full speed during lockout: flame rollout lifting the flame off the sensor
A faulty furnace control board, once everything else checks out

Safe DIY checks

⚠ Before you start

Turn off power at the furnace/HVAC service switch and the breaker before opening panels. Shut the gas valve before any work near the burners, and never disconnect or alter the gas line. If you smell gas, leave the house and call your gas utility.

Confirm the code: look through the sight glass on the blower door and count 1 short flash followed by 4 long flashes. Write it down before you cut power.
Make sure the gas is on: check the manual gas shut-off valve on the pipe to the furnace (handle in line with the pipe) and the on/off switch or knob on the gas valve. If other gas appliances aren't working either, call your gas utility.
Check the furnace filter and replace it if it's dirty; while you have the panel off, look for any obvious disconnected wires around the burner area without touching anything inside the control compartment.
Carrier's controls retry on their own after 3 hours. If the furnace locks out again with code 14, or you see code 34 flashing, the cause still needs fixing.
If you're comfortable doing it with the power and gas off, a technician-style fix Carrier lists is cleaning the flame sensor rod with fine sandpaper or fine steel wool to remove oxide build-up. If you're not sure which part is the sensor, leave it for a pro.
If you smell gas at any point, don't try to relight or reset anything: leave the house and call your gas utility or 911 from outside.

🛠 When to call a pro

Running Carrier's component test to see whether the hot surface igniter glows orange/white hot within the 15-second warm-up, then checking for 115 VAC at the igniter connector and continuity through the harness and igniter.
Checking for 24 VAC at the gas valve on a call for heat, continuity of the gas valve wires back to the control, and whether the valve actually opens (gas should flow at full pressure within 4 seconds).
Measuring flame current with a DC microammeter in series with the flame sensor wire; below 0.5 microamps means cleaning, repositioning or replacing the sensor electrode.
Checking inlet and manifold gas pressure, firing rate, burner carry-over and air leakage around the igniter bracket.
On variable-speed models where the inducer stays at full speed during lockout, investigating flame rollout as Carrier's 58-06T guide describes.
Replacing the furnace control only after the igniter, gas valve, flame sensor and gas supply all check out, as Carrier's troubleshooting steps direct.

Parts that commonly fix it

Always match the part number to your exact model.

⚙

Furnace flame sensor (exact OEM part for your model)

Replace only if cleaning doesn't bring flame current back to the typical range.

[affiliate link slot: AFFILIATE_SLOT_FLAME_SENSOR]

⚙

Hot surface igniter (exact OEM part for your model)

Igniters are fragile and model-specific; match the part number on your furnace.

[affiliate link slot: AFFILIATE_SLOT_HSI_IGNITER]

⚙

Digital multimeter with microamp DC range

For checking igniter voltage and flame sensor current.

[affiliate link slot: AFFILIATE_SLOT_MULTIMETER]

Sources

Last reviewed 2026-10-23. Always confirm against the manual for your exact model number.

Carrier Furnace Code 14: Ignition Lockout (Meaning, Causes, Fixes)

What the code means

Likely causes

Safe DIY checks

🛠 When to call a pro

Parts that commonly fix it

Furnace flame sensor (exact OEM part for your model)

Hot surface igniter (exact OEM part for your model)

Digital multimeter with microamp DC range

Related codes

Sources