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Vaillant aquaPLUS boiler fault and error codes

Are you experiencing a fault code with your boiler? If so, call our 24 hour UK call centre today.

MR Boiler Repairs is the UK’s leading boiler repair and service specialist, providing support for domestic, commercial and residential properties. Our low cost fixed price repair service will provide you with peace of mind and avoid any scary repair bills.

Are you experiencing a fault code with your aquaPLUS boiler? Below you’ll find information on the fault codes for your boiler and the possible reasons for the fault you are experiencing. The aquaPLUS boilers have an inbuilt advanced multifunction diagnostic display to assist with fault finding in the unlikely event of a boiler malfunction. The display features the following four modes

  • Normal Mode
  • Status Mode
  • Diagnostic Mode
  • Fault Mode

Fault and error code information on the aquaPLUS boiler

S00     No heat demand

S01     Fan running

S02     Pimp running 

S03     Ignition sequence 

S04     Burner ignited

S05     Fan and water pump over run

S06     Fan over run

S07     Pump over run

S08     Anti cycling mode

S10     Hot water demand 

S11     Fan running

S13     Ignition sequence 

S14     Burner ignited

S15     Fan and water pump over run

S17     Pump over run

S20     Store recharging 

S21     Fan running

S23     Ignition sequence 

S24     Burner ignited 

S25     Fan and water pump run over

S26     Fan over run 

S27     Pump over run

S28     Anti cycling mode

S30     No heating demand from external controls

S31     Summer mode

S32     Main heat exchanger

S33     Check air/flue system

S34     Frost protection mode

S36     No heating demand from external controls

S39     Contact thermostat has been activated

S53     Delay mode due to lack of water

S54     Delay mode due to flow temperature gradient too steep

Please note that this information is for guidance only and that you should seek technical advice.

If you need a Gas Safe service engineer to repair your boiler then book a boiler repair today.


Vaillant Boiler Manuals / Instructions

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