Overview
The E.02 – .19 error on a Baxi 200/400 combi means the boiler has detected that jumper 1 on the electronics PCB is in a different position from what the board expects. Jumpers are small hardware links on the control PCB used to set configuration or operating modes. The boiler treats an unexpected jumper position as a permanent configuration fault and will lock out until the hardware setting is corrected or the PCB is reconfigured. Severity is moderate: this fault will prevent normal boiler operation but is not an immediate safety emergency unless you smell gas or see damage. The fix is often simple (restore the correct jumper position), but accessing and changing PCB jumpers requires isolating electrical supply and some basic electrical familiarity. If you are not confident working inside a boiler or if the fault returns, you must call a Gas Safe registered engineer — do not attempt gas-valve or PCB repairs yourself.
Possible Cause: Jumper 1 changed – check position of jumper 1.
Troubleshooting Steps
Safety precautions:
- If you smell gas, leave the property immediately and call the gas emergency number. Do not operate electrical switches or the boiler.
- Turn off the boiler using its front controls and isolate the electrical supply at the boiler isolator or consumer unit before removing any covers. Preferably switch off at the mains.
- If you are unsure about working with live equipment, call a Gas Safe engineer. Never work on the gas valve, burners, or PCB wiring unless you are qualified.
Initial checks a homeowner can do:
- Note the exact error code shown (E.02 – .19) and when it started. Note any recent servicing, power cuts, or changes (thermostat, external devices) that might have coincided with the fault.
- Try a single reset of the boiler using the reset button (press per manual instructions, usually 3–10 seconds). Do not repeatedly reset if the code returns.
- Check system water pressure and other simple faults (pressure below 0.5 bar can cause lockouts for other codes) but understand this code refers to jumper/configuration rather than pressure.
Specific diagnostic and fix steps (for competent DIYers only):
1. Obtain or refer to the boiler service manual or wiring diagram to identify the PCB and the position/function of jumper 1 for your exact model and serial.
2. Isolate electrical power to the boiler and wait a short time for capacitors to discharge. Remove the outer case per the manual instructions to expose the PCB. Keep track of all screws and parts.
3. Before touching anything, take clear photos of the PCB and jumper positions so you can restore them if needed.
4. Locate jumper 1 (it will be labelled on the PCB). Compare its current position with the correct/default position shown in the manual or the label on the inside of the boiler cover.
5. If the jumper is in the wrong position and you are comfortable doing so, carefully move it to the correct position using an appropriate tool (avoid shorting pins). Replace the cover, restore power, and reset the boiler.
6. Observe whether the E.02 – .19 fault clears and whether the boiler fires and operates normally. Test hot water and heating briefly.
7. If the fault remains, check for obvious signs of PCB or connector damage (burn marks, loose connectors, corrosion). Do not attempt to repair a damaged PCB. Note any loose wiring at the gas valve connector and PCB headers but do not disconnect or reconnect gas valve internals unless qualified.
When to call a professional:
- If you are unsure about working inside the boiler or moving jumpers.
- If the jumper was already in the correct position or the error returns after correcting it.
- If you see physical damage to the PCB, evidence of water ingress, or persistent communication faults to the gas valve.
- If the boiler locks out repeatedly or other error codes appear.
Contact a Gas Safe registered engineer, provide the exact error code, boiler model and serial, and the photos/notes you took. They can safely diagnose PCB/configuration faults, test communications to the gas valve, and replace or reconfigure components if required.
Helpful Resources
Boiler Manual
Download the official PDF manual for the Baxi 200 / 400 Combi Gas Boiler.