BoilerFaultCodesWhat the manual says
Manufacturer manualOutlet sensor error for having exceeded the max. outlet temperature
What causes this fault?
This fault occurs when the boiler's internal safety sensors detect that the water temperature has risen far beyond its safe operating limit. The most common reasons for this are a failing internal pump that isn't moving the hot water away quickly enough, or a faulty sensor that is providing an incorrect heat reading to the control board.
This issue is more common during the first cold snap of autumn when a pump that has been idle all summer suddenly seizes or struggles to circulate water through the heating system.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Avoid the next call-out bill
A cover plan would handle faults like A17: no call-out fees, no surprise bills.
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