BoilerFaultCodesWhat the manual says
Manufacturer manualInterruption Of Gas Supply or Flame Failure / gas supply has been interrupted, ignition has failed or the flame has not been detected
What causes this fault?
This fault occurs when the boiler attempts to ignite but fails to establish or maintain a steady flame. The most common reasons include a lack of gas reaching the unit, a worn-out ignition spark, or a sensor that can no longer detect the flame once it is lit.
This fault is notably common during extreme cold snaps, as the external condensate drainage pipe can freeze and back up, preventing the boiler from lighting.
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 E133: no call-out fees, no surprise bills.
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Related fault codes
All 21 fault codes on the Promax HE Store
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