The flue safety device has tripped because flue gases got too hot or a flue fault was detected.
Most common on: Baxi 600, Baxi 800, EcoBlue, Platinum+, Duo-tec
E131 relates to the flue gas thermostat (flue safety device). It trips when the temperature of the flue gases rises beyond a safe limit, or when the device detects a problem, and the boiler shuts down to prevent unsafe operation.
Because it is a flue and combustion safety code, it should not be repeatedly reset. It can indicate a blocked or restricted flue, a heat exchanger problem or a faulty thermostat, all of which need a Gas Safe engineer to investigate before the boiler is used again.
Visually check the external flue outlet is not blocked by debris, leaves or nesting. Do not dismantle any part of the flue yourself.
This is a flue safety code. Reset once at most — if E131 returns, leave the boiler off and book an engineer rather than resetting repeatedly.
A tripped flue safety device needs a Gas Safe engineer to check the flue, heat exchanger and thermostat and confirm the boiler is safe before further use.
Work on the gas side of a boiler must be carried out by a Gas Safe registered engineer. The checks above are limited to safe, non-invasive things a homeowner can look at (pressure, resets, the gas supply) — if in doubt, stop and call an engineer.
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The flue safety device has tripped because flue gases got too hot or a flue fault was detected. E131 relates to the flue gas thermostat (flue safety device). It trips when the temperature of the flue gases rises beyond a safe limit, or when the device detects a problem, and the boiler shuts down to prevent unsafe operation.
You can try a single reset and the safe checks below, but Baxi E131 usually needs a Gas Safe registered engineer. Never work on the gas side of a boiler yourself — it is illegal and dangerous unless you are Gas Safe registered.
A recurring E131 means the underlying cause has not been fixed — most often blocked, restricted or incorrectly fitted flue. Resetting repeatedly will not solve it; get the boiler diagnosed properly.
Flue gas (NTC) thermistor fault
Overheat — primary circuit too hot
Fan fault
See all Baxi fault codes.