BoilerFaultCodesWhat the manual says
Manufacturer manualService Mode / Sequence indicator following SH
What causes this fault?
This code appears when the boiler has been manually put into a specific testing mode, typically by an engineer during a service or installation. It indicates that the system is running at a fixed rate to check performance rather than responding to your thermostat. It is not caused by a mechanical failure, but rather by the control dial being left in a certain position or a button sequence being activated.
DIY fix possible
Wait 5 to 15 minutes for the boiler to automatically exit the service modeRotate the main mode dial back to the 'Off' position and then back to 'On/Winter'Press the 'Reset' button once to clear the display
Avoid the next call-out bill
A cover plan would handle faults like UF: no call-out fees, no surprise bills.
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