What It Means
- Low pressure switch failed open.
- Pressure switch failed open.
- SLP98UHV, SLP99UHV: Low pressure switch failed open - Refer to troubleshooting in installation instruction.

Ducted Heating
E223 means different things on different Ducted Heating models. Enter your model number to see only your reading, or find your model below.
EL280UHE(X), EL280UHEK, EL280UHEK(X), EL296UHE, EL297UHEK, ML296UHVK, ML297UH045XV36BK, ML297UH070XV36BK, ML297UH090XV36CK, ML297UH090XV60CK, ML297UH110XV60CK, ML297UH135XV60DK, ML297UHVK, SL280DFNV, SL280UHV, SL297UHNV
Gas furnace (indoor)
Check pressure (inches w.c.) of low pressure switch clos- ing on heat call. Measure operating pressure (inches w.c.). Inspect vent and combustion air inducer for correct opera- tion and restriction. Resumes normal operation after fault is cleared
SL280DFNV, SL280UHV, SL297UHNV
Check pressure (inches w.c.) of low pressure switch closing on heat call. Measure operating pressure (inch- es w.c.). Inspect vent and combustion air inducer for correct operation and restriction. Resumes normal op- eration after fault is cleared
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.
Low pressure switch failed open.
EL280UHEK, EL280UHEK(X)
Low pressure switch failed open.
Low pressure switch failed open.
Low pressure switch failed open.
ML297UH045XV36BK, ML297UH070XV36BK, ML297UH090XV36CK, ML297UH090XV60CK, ML297UH110XV60CK, ML297UH135XV60DK, ML297UHVK
Low pressure switch failed open.
Low pressure switch failed open.
Low pressure switch failed open.
Low pressure switch failed open.
Low pressure switch failed open.
EL180UHNE(K), EL195UHNEK, EL195UHNEK-01, EL195UHNEK-02, EL196UHEK, ML180UHVK, ML193DFEK, ML196UHEK
Gas furnace (indoor)
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.
Pressure switch failed open.
Pressure switch failed open.
EL195UHNEK, EL195UHNEK-01, EL195UHNEK-02
Pressure switch failed open.
Pressure switch failed open.
Pressure switch failed open.
Pressure switch failed open.
Pressure switch failed open.
Models: SLP98UHV, SLP99UHV
Check inches of water column pressure during operation of low pressure switch on heat call, measure inches of water column of operating pressure, inspect vent and com- bustion air inducer for correct operation and restriction.
SLP99UHV
Check inches of water column pressure during operation of low pressure switch on heat call, measure inches of water column of operating pressure, inspect vent and combustion air inducer for correct operation and restriction.
Low pressure switch failed open − Refer to troubleshooting in installation instruc- tion.
Low pressure switch failed open - Refer to troubleshooting in installation instruction.
Continue in ACLogics with guided diagnosis for your equipment and symptoms.