The Baxi A.02.46 code means “Device priority error.” It is a technical control-system message. The code indicates that the boiler has detected a problem with how priority is assigned between devices or functions, but Baxi’s public fault table does not identify the devices involved.
Record the full code exactly, note whether heating and hot water are working, and check your complete boiler model. Do not change technical priorities, disconnect controls or enter installer menus. A persistent A.02.46 message needs a suitably qualified engineer.
What does Baxi A.02.46 mean?
Baxi lists A.02.46 as a device priority error for its current Combi 2 and System 2 model group. Boiler control systems can use priorities so that connected parts and functions operate in the intended order. The public description tells you that this ordering has produced an error; it does not explain which device has priority or which one should have it.
That distinction prevents a common mistake. A.02.46 is not proof that your room thermostat, programmer, app connection or boiler circuit board is faulty. It is also not an instruction to choose one device over another yourself.
Which Baxi boilers can show A.02.46?
The current Baxi list covers Baxi 200, 400, 600 and 800 Combi 2 boilers, Baxi Assure 500 Combi 2, Baxi 600 and 800 System 2, and Baxi Assure 500 System 2. A similar code on a different range may have a different meaning, so confirm the full model name from your paperwork or an accessible external label.
Do not remove the casing to find product information. The engineer can use the exact model and installation history to select the correct technical information.
What does device priority mean?
At homeowner level, priority is simply the order in which a control system expects different requests or connected functions to be handled. The exact arrangement depends on the boiler and installed controls. Baxi’s public code description does not name those controls, so it would be misleading to list a specific thermostat, sensor or accessory as the cause.
The code may follow installation, commissioning, a controls change, repair work or an interruption to power, but those are possible circumstances rather than confirmed causes. The engineer must check what is actually connected and how the boiler is configured.
What can you safely check?
Useful external observations include:
- Confirm that the display reads A.02.46, including the dots and leading zero.
- Photograph the message and any other code that appears.
- Record the full boiler model.
- Note whether heating, hot water or both are unavailable.
- Check the visible status of ordinary room controls without changing technical settings.
- Note whether the code appeared after a power cut, installation, service visit or controls work.
Do not unplug accessories or try different wiring combinations. A connected control can appear normal while the boiler still reports a priority problem, and disturbing the setup may hide useful evidence.
Can you reset a Baxi A.02.46 code?
You can try the normal homeowner reset once if the official user guide for your exact model explains how. Baxi reset methods vary between ranges, so do not copy a button sequence from another boiler. If A.02.46 stays on screen, returns or normal heating and hot water do not resume, stop resetting and arrange a repair.
A factory reset is not an ordinary boiler reset. Do not use factory, installer, commissioning or parameter menus to try to clear this code.
What should you avoid doing?
Keep the boiler casing closed. Do not alter device-priority settings, pairing arrangements, bus connections, plugs, wiring or circuit boards. Do not buy replacement controls on the assumption that one named device has failed. The public code description does not support that conclusion.
A qualified engineer can check the installed control arrangement, review the code history and make model-specific tests safely. That is the reliable route to the correct repair.
Is A.02.46 dangerous?
Baxi describes A.02.46 as a device priority error, not as a gas-leak or carbon-monoxide warning. However, a boiler with a persistent technical error should not be bypassed or repeatedly restarted.
If you smell gas, suspect carbon monoxide, feel unwell near the appliance or a carbon-monoxide alarm sounds, leave the property and follow current emergency guidance. Do not wait for a standard repair appointment.
Who should fix Baxi A.02.46?
A suitably qualified Gas Safe registered engineer should investigate. They can confirm the exact appliance, identify the relevant controls without guesswork and determine the work needed to restore normal operation. Give them the code photograph, full model and details of any recent electrical or controls work.
Want the A.02.46 fault dealt with?
Book a fixed-price boiler repair aimed at fixing the fault, with the booking price clear before the visit.
Quick answers about Baxi A.02.46
What does A.02.46 mean?
Baxi defines A.02.46 as “Device priority error.” It concerns the ordering expected within the boiler’s control arrangement.
Which device is causing the error?
The public Baxi table does not say. Do not assume it is the thermostat, programmer, app control or boiler PCB.
Can I change device priority myself?
No. Priority and configuration settings are technical controls that should be checked by a suitably qualified engineer.
Will a reset clear A.02.46?
One model-approved reset may clear a temporary interruption. If the code returns, repeated resets are not a repair.
Does the code mean I need a new thermostat?
No. A.02.46 does not identify a failed thermostat or any other specific component.
What should I record?
Keep the exact code, model name, heating and hot-water status, other messages and details of recent work or power interruptions.