System Diagnosis
High Pressure Switch Open. The high pressure switch is open (Cooling/Heat Pump).
Troubleshooting guide for the Lennox Numeric Codes (E-Codes) system fault E225.
Pressure and temperature readings that stay out of range after airflow is verified.
Dirty coils or airflow restrictions can look like a charge problem until the air side is cleaned up.
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AI isolates the likely numeric codes (e-codes) branch behind code E225
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