271
Moderate
Lennox · HVAC Systems (AC, Furnaces & Heat Pumps)
Flame Current Leaves Acceptable Range
Quick Answer
Error code 271 on your Lennox HVAC Systems (AC, Furnaces & Heat Pumps) means: Flame Current Leaves Acceptable Range. This is usually fixable — see the step-by-step guide below.
Likely Causes
How to Fix It
1
Monitor flame current over several minutes to identify fluctuation patterns
2
Clean the flame sensor and check for stable readings above 1.5 microamps
3
Check gas pressure stability during operation with a manometer
4
Inspect the flame sensor insulator for hairline cracks
5
Replace the flame sensor if current readings are erratic after cleaning
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
Flame sensor
Flame sensor gasket
Gas pressure regulator (if unstable)
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