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E78 FAULT CODE
Potterton

Water Pressure Sensor Fault

Medium Severity Engineer Required

The water pressure sensor is giving an incorrect reading. May indicate a blocked or failed sensor.

Step-by-Step Fix Guide

  1. Step 1

    Check system pressure is correct

  2. Step 2 Engineer only

    If pressure is correct but E78 persists, the sensor may be blocked or failed — 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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