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PUMP FAULT FAULT CODE
Myson

Pump Not Running

High Severity Engineer Required

The circulation pump is not running. On Marathon models the pump is internal.

Step-by-Step Fix Guide

  1. Step 1

    Check the pump is not seized — it may need manual freeing after summer

  2. Step 2 Engineer only

    A Gas Safe engineer should check pump wiring and operation

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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