BoilerFaultCodesWhat the manual says
Manufacturer manualBreak in communication to weather compensating clip-in control or Greenstar Comfort II RF
From this model's manual
Verified against the Worcester Bosch/Worcester Bosch Greenstar I Junior installation & service manual.
DIY fix possible
Locate the thermostat or programmer clipped into the front of the boiler or mounted on the wall.Check if the batteries in your wireless thermostat need replacing.Try resetting the connection between the transmitter and the receiver by following the pairing instructions in your user manual.
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Related fault codes
All 38 fault codes on the Greenstar 24i / 28i Junior
Seeing a different code? Every code this model can display, in one place.
2 pulses2 pulses / No light2 pulses No light5 pulses5 pulses / No light5 pulses No light6a1213141516171819109115Blue indicator light flashingBlue indicator light offBlue light onDouble flash Blue lightEAERRORFAFast flashFast flash (Reset button Off)Fast flash / FlashingFast flash / Not a fault codeFast flash / OffLOCKOUTNo lightNo light / Not a fault codeOff (No light)Off / OffOn / OffSlow flashSteady on (Burner lit)