Carrier Error Code 32: Low Flame Sense
LED Blink Pattern
3 short blinks, 2 long blinks.
How to Fix Carrier Code 32
- Step 1: Check your furnace filter. A dirty filter restricts airflow, which can affect the burner flame. Replace it if needed.
- Step 2: Ensure the furnace's gas supply is turned on. Check the shut-off valve near the furnace and the main gas supply to your home.
- Step 3: Reset the furnace by turning off the power at the breaker for a minute, then turning it back on. If the error persists, call a qualified HVAC technician.
How to Reset Carrier Code 32
- Turn off the furnace power switch, usually located on or near the unit.
- Turn off the circuit breaker for the furnace. Wait 30 seconds.
- Restore power at the breaker and flip the furnace switch back on.
- Set the thermostat to call for heat. If the error code returns after 2-3 ignition attempts, the fault requires repair.
Resetting clears the code from the display but does not fix the underlying fault. If the code returns after reset, proceed to the diagnostic steps above.
What Does Carrier Error Code 32 Mean?
The Carrier error code 32, or a blinking LED pattern indicating 'Low Flame Sense,' means the furnace's control board isn't detecting a stable flame after ignition. The furnace goes through its normal start-up sequence, the gas valve opens, and the burners light. However, the flame sensor, a small metallic rod in the flame, isn't sending a strong enough signal back to the control board to confirm the flame is present. Because the furnace cannot reliably verify the flame, it shuts down as a safety precaution. This issue can stem from a few different problems, ranging from a dirty flame sensor to a more serious gas supply issue. Because gas furnaces are involved, it's important to address this issue promptly to ensure safe and reliable heating.
Common Causes
- Dirty or corroded flame sensor
- Weak flame signal due to improper grounding
- Faulty flame sensor
- Low gas pressure
- Defective gas valve
Diagnostic Steps
| If... | Check | Expected |
|---|---|---|
| Furnace attempts ignition but fails to maintain flame | Measure flame sensor microamps (uA) during operation | At least 2 uA DC |
| Low microamp reading | Inspect flame sensor for dirt/corrosion; clean with steel wool | Visibly clean sensor |
| Clean sensor, but still low uA | Check furnace grounding; measure resistance from furnace chassis to ground | Less than 1 ohm |
| Good ground, clean sensor, still low uA | Measure gas pressure at the gas valve | Within manufacturer's specified range (typically 3.5-4.0" WC for natural gas) |
Applicable Carrier Models
- 24ABC6 Air Conditioner(electric)
- 25HBC5 Heat Pump(electric)
- Base Series(gas)
- Base Series Furnace(gas)
- Comfort 80 Gas Furnace(gas)
- Comfort Series(electric)
- Comfort Series Furnace(gas)
- Comfort Series Heat Pump(electric)
- Infinity 20 Heat Pump with Greenspeed Intelligence(electric)
- Infinity 80(gas)
- Infinity Series(electric)
- Infinity Series Furnace(gas)
- Infinity Series Heat Pump(electric)
- Performance Boost 95 Furnace(gas)
- Performance Boost Furnace(gas)
- Performance Series(gas)
- Performance Series Furnace(gas)
- Performance Series Heat Pump(electric)
- WeatherMaker 8000(gas)
- WeatherMaker 9300(gas)
- WeatherMaker Furnace(gas)
Replacement Parts
| Part | OEM Number | Est. Cost | Where to Buy |
|---|---|---|---|
| Flame Sensor | KH42LZ010 | — | Find Part |
| Gas Valve | EF32CW225 | — | Find Part |
| Ignition Control Module | — | — | — |
Related Codes on Same Models
Other codes that affect the same Carrier model families as 32.
| Code | Description | Severity |
|---|---|---|
| 12 | Blower On After Power Up | Warning |
| 13 | Limit/Rollout Fault | Critical |
| 14 | Ignition Lockout | Critical |
| 21 | Gas Heating Lockout | Critical |
| 22 | Abnormal Flame | Critical |
| 23 | Pressure Switch Fault | Warning |
| 24 | Secondary Voltage Fuse | Warning |
| 31 | High Stage Pressure Fault | Warning |
| 33 | Limit/Rollout Switch Lockout | Critical |
| 34 | Ignition/Flame Sense Fault | Warning |