Fault codes / Furrion FWH09 / E4

Furrion FWH09 code E4

What it means: Inlet temperature sensor fault.

What to check

Reseat and measure the inlet sensor. Replace if open or shorted.

Learn the system

• Tank water heaters
• Tankless water heaters
• Water heater gas side

Practice it on a service call

• No hot water on electric
• Water heater lights, then goes out
• Water heater lights then faults

Guided diagnosis

• Water Heater

Other Furrion FWH09 codes

• Furrion FWH09 code E0 Outlet temperature fault
• Furrion FWH09 code E1 No flame sensed at ignition
• Furrion FWH09 code E2 False flame sensed
• Furrion FWH09 code E3 Overtemperature sensor
• Furrion FWH09 code E5 Air pressure fault
• Furrion FWH09 code E6 Temperature surge
• Furrion FWH09 code E7 Solenoid fault

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.