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E03 FAULT CODE
Keston

Boiler Overheat

High Severity Engineer Required

The boiler has overheated — check for closed valves, air in system, or incorrect water pressure.

Step-by-Step Fix Guide

  1. Step 1

    Turn off and allow to cool

  2. Step 2

    Check system pressure and ensure all valves are fully open

  3. Step 3

    Bleed radiators

  4. Step 4

    Reset once

  5. Step 5 Engineer only

    If fault returns, call a Gas Safe engineer

Gas Safe Reminder

Work on gas appliances must be carried out by a Gas Safe registered engineer. The steps above cover safe checks a homeowner can perform - any internal component replacement requires a qualified professional. If in doubt, always call an engineer.

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