Furrion FWH09 tankless water heater fault codes
Furrion FWH09 (2.4 GPM class), about 60,000 BTU. Gas inlet about 11 to 14 in W.C. Water pressure about 7.2 to 65 PSI. Minimum flow about 0.32 GPM. Temperature about 95 to 124 F. 10 A fuses.
Furrion FWH09 code E0
Outlet temperature fault. Reseat and measure the outlet sensor. Replace if open or shorted. Check the connector for water.
Furrion FWH09 code E1
No flame sensed at ignition. Gas supply, valves, regulator pressure under load, tank level, igniter and flame sensor condition, air in the line after a tank change.
Furrion FWH09 code E2
False flame sensed. A stuck gas valve or a shorted flame sensor. Gas valve problems need a service replacement. Check wiring first.
Furrion FWH09 code E3
Overtemperature sensor. Run cold water through for 10 to 20 seconds, then restart. If it returns, check the sensor and thermistors.
Furrion FWH09 code E4
Inlet temperature sensor fault. Reseat and measure the inlet sensor. Replace if open or shorted.
Furrion FWH09 code E5
Air pressure fault. Exhaust or intake blocked, wind pushing into the vent, a cracked hose, or a failing pressure switch. Clear the vent first.
Furrion FWH09 code E6
Temperature surge. Cold-water surge, crossover between hot and cold, low flow, air in the lines, or a plugged inlet filter. Check plumbing and mixing valves.
Furrion FWH09 code E7
Solenoid fault. Check the solenoid plug and coil resistance. Replace the valve assembly if open.
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Full field guide: Furrion FWH09 tankless water heater
Codes come from the maker manuals and public service sheets. Your model's own chart always wins, and LP and 120 volt work belongs to a qualified technician.