214
Easy Fix
Lennox · HVAC Systems (AC, Furnaces & Heat Pumps)
Flame Sense Lost During Operation
Quick Answer
Error code 214 on your Lennox HVAC Systems (AC, Furnaces & Heat Pumps) means: Flame Sense Lost During Operation. This is usually fixable — see the step-by-step guide below.
Likely Causes
How to Fix It
1
Remove the flame sensor and clean it with fine emery cloth or Scotch-Brite pad
2
Measure flame current with a microamp meter during burner operation (should be above 1.0 microamps)
3
Verify the furnace chassis is properly grounded with a multimeter
4
Check gas pressure stability during operation to rule out fluctuations
5
Replace the flame sensor if cleaning does not restore adequate flame signal
Pro Tip
This is a common issue that most users can resolve without specialized tools. Try the first step before moving on to more complex solutions.
Parts You May Need
Flame sensor
Emery cloth
Flame sensor gasket
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