Vokera water heater displays code 03, fan runs but ignition does not occur or appliance locks out on air pressure fault

Safety first: Isolate electrical power before removing any covers. Do not dismantle the flue system yourself.

Owner checks:

• Inspect the external flue terminal: Ensure it is not obstructed by leaves, plastic bags, snow, or insect nests.
• Check for adequate ventilation: Make sure vents and grilles around the appliance are not blocked by cupboards, boxes, or other items.
• Attempt a single reset from the control panel. If the code returns, stop resetting.

Engineer actions:

• Test the air pressure switch for correct switching at the specified fan pressure and replace if defective.
• Inspect and clean the fan assembly, ensuring the impeller is free of debris and spins freely; replace the fan motor if noisy or seized.
• Check the silicone pressure tubes for splits, kinks, or blockages and replace as needed.
• Verify the flue system is correctly installed, sealed, and not internally blocked.

Because combustion and flue safety are involved, internal diagnosis should be left to a qualified Vokera technician.