E110 — Primary Water Overheat

What does E110 mean?

This code signifies that the primary water in the boiler has exceeded safe operating temperatures, causing an overheat safety lockout. The display shows 'E1' alternating with '10'.

• Poor circulation in the heating system.
• Faulty pump.
• Blocked heat exchanger.
• sensor malfunction leading to incorrect temperature reading.

Click steps to track your progress.

1. 1

   Turn the selector switch fully anticlockwise to the 'Reset' position and hold for 5 seconds.

2. 2

   Check that all external heating controls (thermostats, programmers) are properly calling for heat.

3. 3

   Ensure radiators are open and not blocked to allow for proper water flow.

4. 4

   If the error reappears, contact a qualified heating engineer to check the pump and circulation system.