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F74 FAULT CODE
Glow-worm

Water Pressure Sensor Signal Too High

High Severity Engineer Required

The pressure sensor is reading above its expected operating range, indicating a faulty sensor or very high system pressure.

Step-by-Step Fix Guide

  1. Step 1

    Do not repressurise the boiler

  2. Step 2 Engineer only

    Call a Gas Safe engineer to test the pressure sensor and system pressure

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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