What It Means
- Low pressure switch failed closed.
- Pressure switch failed closed.
- SLP98UHV, SLP99UHV: Low pressure switch failed closed - Refer to troubleshooting in installation instruction.
Lennox Ducted Heating
Lennox Error Code E224
Ducted Heating
E224 means different things on different Ducted Heating models. Enter your model number to see only your reading, or find your model below.
Causes & actions from Lennox
Low pressure switch failed closed.
16 models
EL280UHE(X), EL280UHEK, EL280UHEK(X), EL296UHE, EL297UHEK, ML296UHVK, ML297UH045XV36BK, ML297UH070XV36BK, ML297UH090XV36CK, ML297UH090XV60CK, ML297UH110XV60CK, ML297UH135XV60DK, ML297UHVK, SL280DFNV, SL280UHV, SL297UHNV
Gas furnace (indoor)
How it shows
- Integrated control 7-segment display: E224
Check operation of low pressure switch to see if it is stuck closed on heat call longer than 150 seconds. Measure oper- ating pressure (inches w.c.). Inspect vent and combustion air inducer for correct operation and restriction. Resumes nor- mal operation after fault is cleared.
Other manual wording (1 of 2)
SL280DFNV, SL280UHV, SL297UHNV
Check operation of low pressure switch to see if it is stuck closed on heat call longer than 150 seconds. Mea- sure operating pressure (inches w.c.). Inspect vent and combustion air inducer for correct operation and restric- tion. Resumes normal operation after fault is cleared.
Other manual wording (2 of 2)
EL280UHE(X), EL296UHE
Check pressure (inches w.c.) of low pressure switch closing on heat call. Measure operating pressure (inches w.c.). Inspect vent and combustion air inducer for correct operation and restriction. Resumes normal operation after fault is cleared.
Applicable models & manual sources
- EL280UHEK
Low pressure switch failed closed
EL280UHEK, EL280UHEK(X)
- EL297UHEK
Low pressure switch failed closed
- ML296UHVK
Low pressure switch failed closed
- ML297UH045XV36BK
Low pressure switch failed closed
ML297UH045XV36BK, ML297UH070XV36BK, ML297UH090XV36CK, ML297UH090XV60CK, ML297UH110XV60CK, ML297UH135XV60DK, ML297UHVK
- SL280DFNV
Low pressure switch failed closed.
- SL280UHV
Low pressure switch failed closed.
- SL297UHNV
Low pressure switch failed closed.
- EL280UHE(X)
Low pressure switch failed closed.
- EL296UHE
Low pressure switch failed closed.
Pressure switch failed closed.
8 models
EL180UHNE(K), EL195UHNEK, EL195UHNEK-01, EL195UHNEK-02, EL196UHEK, ML180UHVK, ML193DFEK, ML196UHEK
Gas furnace (indoor)
How it shows
- Integrated control 7-segment display: E224
Check pressure (inches w.c.) of pressure switch closing on heat call. Measure operating pressure (inches w.c.). Inspect vent and combustion air inducer for correct operation and restriction. Resumes normal operation after fault is cleared.
Applicable models & manual sources
- EL180UHNE(K)
Pressure switch failed closed.
- EL195UHNEK
Pressure switch failed closed.
EL195UHNEK, EL195UHNEK-01, EL195UHNEK-02
- EL196UHEK
Pressure switch failed closed.
- ML180UHVK
Pressure switch failed closed.
- ML193DFEK
Pressure switch failed closed.
- ML196UHEK
Pressure switch failed closed.
- ML196UHEK
Pressure switch failed closed.
Low pressure switch failed closed - Refer to troubleshooting in installation instruction.
Models: SLP98UHV, SLP99UHV
How it shows
- Integrated control 7-segment display: E224
Check low pressure switch for closed contacts, measure inches of water column of operating pressure, inspect vent and combustion air inducer for correct operation and re- striction.
Other manual wording
SLP99UHV
Check low pressure switch for closed contacts, measure inches of water column of operating pressure, inspect vent and combustion air inducer for correct operation and restriction.
Applicable models & manual sources
- SLP98UHV
Low pressure switch failed closed − Refer to troubleshooting in installation instruc- tion.
- SLP99UHV
Low pressure switch failed closed - Refer to troubleshooting in installation instruction.
Disclaimer: This information is for general reference. Code wording and instructions vary by model. Always follow the service manual for your exact unit.
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