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37 FAULT CODE
Johnson & Starley

Low Water Pressure (Numeric Display)

Low Severity DIY Check Possible

On Johnson & Starley numeric display models, code 37 indicates low system water pressure.

Step-by-Step Fix Guide

  1. Step 1

    Repressurise to 1.5 bar

  2. Step 2

    Reset

  3. Step 3

    Contact a Gas Safe engineer if pressure keeps dropping

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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