Fault codes / Girard GSWH-2 / E0
Girard GSWH-2 code E0
What it means: Outlet water thermistor open or shorted.
What to check
Reseat the sensor plug. Look for water or corrosion on it. Measure ohms: a good sensor gives a steady value that moves as it warms. Open or zero: replace it.
Learn the system
Practice it on a service call
Guided diagnosis
Other Girard GSWH-2 codes
- Girard GSWH-2 code E1 Ignition failed or flame lost at start
- Girard GSWH-2 code E2 Flame lost while running
- Girard GSWH-2 code E3 Eco (high-limit) switch is open
- Girard GSWH-2 code E4 Inlet water thermistor open or shorted
- Girard GSWH-2 code E5 Blower fault
- Girard GSWH-2 code E6 Outlet water over 140 F for 3 seconds
- Girard GSWH-2 code E7 Linear gas valve open circuit
- Girard GSWH-2 code E8 Air pressure switch fault
- Girard GSWH-2 code E9 Flame sensed before ignition or a short
- Girard GSWH-2 code Fd Freeze protection is active
- Girard GSWH-2 code En Run timer ended
Full field guide: Girard GSWH-2 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.