Error E.02 – .00

Safety precautions:

1) If you smell gas, hear a hissing sound, or suspect a gas leak, leave the property immediately and call the gas emergency number. Do not operate electrical switches or the boiler.

2) If you or anyone in the property feels unwell with headaches, nausea, dizziness, or flu-like symptoms and you suspect carbon monoxide, get fresh air immediately and call the emergency services and a Gas Safe engineer. Do not attempt internal repairs.

3) Only perform non-invasive checks described below. Do not open the boiler, touch internal components, or attempt gas or electrical repairs unless you are a qualified engineer.

Initial checks a homeowner can do:

1) Confirm whether you or someone else pressed the reset button or turned the selector to R recently. The code E.02 – .00 may simply reflect that action. If so, wait a few minutes for the boiler to complete the reset and try to run the heating or hot water demand again.

2) Check the display and any other fault lights. Make a note of any additional error codes or flashing lights if they appear after the reset attempt.

3) Check the mains power to the boiler is on and the room thermostat/timer is calling for heat or hot water (so the boiler has a valid demand to start).

4) Check the system pressure gauge. Baxi boilers typically need about 1.0–1.5 bar when cold. If pressure is below ~0.5 bar the boiler may lock out and show other codes; if pressure is low, repressurise to the recommended range following the boiler manual.

Practical restart and simple fixes:

1) Allow the boiler to finish its reset sequence. If the reset has just been pressed, wait 5–10 minutes and see if the boiler fires and the temperature display returns to normal.

2) If nothing happens, try a single manual reset following the Baxi guidance: press and hold the reset button (or turn the selector to R) for the time specified in your manual or about 3–5 seconds, then release. Do not press the reset repeatedly in short succession — allow the boiler to attempt restart between tries.

3) If the boiler still does not start, perform a power cycle: switch off the boiler at the isolator/switch, wait 60 seconds, and switch it back on. Wait a few minutes to see if the boiler clears the code and fires.

4) If system pressure is low and you know how to use the filling loop, repressurise the system to the recommended pressure (typically 1.0–1.5 bar). Open the filling loop valves slowly, watch the pressure gauge, and close the valves when in range. If you are unsure how to do this, stop and call your installer or engineer.

5) In cold weather check the condensate pipe for freezing or blockage (a frozen/blocked condensate can cause lockouts on combi boilers). If frozen, thaw the pipe with warm (not boiling) water or use a suitable thawing method. If blocked with debris, call an engineer.

Diagnostics to record and when to stop:

1) If the E.02 – .00 message persists after the above steps, or the boiler locks out again shortly after a successful restart, record when the lockouts occur, whether heating or hot water was being used, and any other error messages or unusual noises.

2) If other error codes appear alongside or after E.02, note them exactly — they give the engineer diagnostic information.

3) Do not attempt internal electrical or gas checks. Repeated resets are not a long-term fix and can hide a developing fault.

When to call a professional:

1) Call a Gas Safe registered engineer if the boiler will not restart after a proper reset and power cycle, if the code keeps recurring, if you see other fault codes, if system pressure will not hold, or if you suspect a gas, flue, fan, PCB or sensor fault.

2) Call an engineer immediately if you detect a gas smell, suspect a carbon monoxide issue, or the boiler behaves dangerously.

Summary guidance:

E.02 – .00 usually means a reset is in progress or was triggered and is often resolved by waiting or a single correct reset. If the code remains, repeats, or is accompanied by other faults, stop DIY attempts and contact a qualified Gas Safe engineer to diagnose and repair the underlying cause.