F00 Water high temperature (ECO)

What the control is telling you

Water in the boiler overheated. Lockout; pump runs to cool the boiler. Control: FAULT light red steady and LOCKOUT shown on lower line; reset with RESET held over 1 second after repair.

Applies to: EL-80, EL-110, EL-150, EL-220, EL-299, EL-399 (N/LP)

Likely causes

• Circulator not running
• No water or no flow through the system
• Zone or ball valves in the wrong position
• Water ECO sensor wiring fault or failed ECO sensor

Test and repair steps

1. Check circulator operation
2. If the pump runs, confirm there is water in the system and it is moving; check zone and ball valves
3. Look at the temperature/pressure gauge if the water is not hot, check the ECO sensor wiring and repair
4. If wiring is good and water is not hot, replace the ECO sensor
5. Press RESET after repair

Models that show this code

12 models in Elite EL

Other codes on the same units

• E03 System sensor failure (cascade)
• E07 Flue temperature high
• E19 Line voltage frequency out of range
• F01 Flue temperature switch / low water
• F02 Supply sensor failure
• F03 Return sensor failure
• F04 Flue sensor failure
• F05 Supply temperature high