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Error code reference
Lennox Furnace Error Code E224
Low pressure switch failed closed (stuck closed on heat call longer than 150 seconds).
SourceLennox EL296DFE Series Furnace - Full Service Manualp. 12
Diagnostic procedure
The full E224 procedure
Step 1 is visible so you can confirm you are on the right page. The remaining steps, the ones that tell you whether to actually replace a part, unlock with any pass.
MyPros+ · DiagnosticsStep 1 preview
1
First diagnostic step
Check operation of low pressure switch to see if it is stuck closed. Measure operating pressure. Inspect vent and combustion air inducer for correct operation and restriction.
SourceLennox EL296DFE Series Furnace - Full Service Manualp. 12
More steps, wiring diagram references, and verified part numbers
Includes expected resistance and voltage values, connector pinouts, and supersession notes for replacement parts.
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Where this code is documented
3 manuals in the MyPros+ library document this code for Lennox furnace.
Models covered by the manuals that document this code
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