What do the error symbols mean on my boiler?

  Siphon fill mode. The boiler will run at a low burn for about 15 minutes to fill the condense trap. This happens after the boiler has been turned off, if it hasn't been used for a day or so, and if the control knob has been turned down and back up. This is perfectly normal - it is a safety feature of the boiler. It will last about 15 minutes, the boiler will then go back to normal. If the boiler does this for more than half an hour, please ring us on 0330 123 9559
  Key Lock (child lock) - the front panel has been locked (New Greenstar 24/28 only)
  One key has been pressed
  Two keys have been pressed at once
  The boiler is operating in maximum mode. This should not last any longer than 15 minutes. Leave the boiler alone for 15 minutes, if the symbol is still showing after 15 minutes, please ring us on 0330 123 9559 to arrange an appointment.
  The boiler is operating within a set range (service function 1A). Please ring our technical department on 0330 123 3366.
  The boiler is operating in minimum mode. This should not last any longer than 15 minutes. Leave the boiler alone for 15 minutes, if the symbol is still showing after 15 minutes, please ring us on 0330 123 9559 to arrange an appointment.
  Air purge mode. The boiler will not fire, but will pulse the pump on and off. This should only happen when the boiler is first switched on after installation, or if a circuit board is changed. It will last about 15 minutes, then the boiler will go back to normal operation. If the boiler does this for more than half an hour, please ring to arrange an appointment on 0330 123 9559.
  'Save' function - this is only seen when an adjustment is made in the menus, and then saved. Does not appear in normal operation.
  Temperature blocking mode ('Gradient limitation'). The boiler is programmed to increase its flow temperature by a certain number of degrees per minute. If it exceeds that rate, then this symbol will appear, the burner will stop for two minutes, and will restart afterwards. It means that the flow temperature is increasing too quickly - not really an overheat as such, but it can mean there is a circulation issue. It can also happen on initial installation, especially with the CDi Conventionals. If continues, please ring 0330 123 9559 to arrange an engineer appointment.
  The display will flash between this symbol and the flow temperature. On this model of boiler it means the service is due.
  The display will flash between this symbol and the flow temperature. The heating circuit pump is blocked, please ring 0330 123 9559 to arrange an engineer appointment.
  The SE Code is not a fault, it is a function that is displayed when the boiler has run for 2324 hours, which is average for a 12 month period. And therefore is due for a Service. Please ring 0330 123 9559 to arrange a Service.

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