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E40 FAULT CODE
Main Heating

CH Return Sensor Error

Medium Severity Engineer Required

Central heating return sensor has a fault on Main Eco Compact boilers.

Step-by-Step Fix Guide

  1. Step 1 Engineer only

    Call a Gas Safe engineer to test the return sensor

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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