The underlying cause, often the pump, needs an engineer. Repeatedly resetting an overheat fault isn't safe.

E110Baxi

Baxi E110: overheat: the safety thermostat has tripped

Checked against Baxi's own documentation: Baxi: boiler error codes. Last reviewed October 2026. How we check

Engineer only

The boiler got too hot. Baxi lists a jammed pump or air in the system as likely causes.

What you can safely do

There is nothing you can safely do yourself with this one. Leave the boiler off and book an engineer.

Write down the code exactly as the display shows it: E110.
Find your boiler's model name. It is usually on the front panel or in the user manual. The table below shows why it matters: Baxi codes can mean different things on different models.
Note when it started and what the boiler was doing (heating, hot water, or starting up).
If the boiler is still under warranty, check your warranty paperwork before you book anyone.

Find a Gas Safe engineer near you Opens the official Gas Safe Register search.

Applies to Platinum, Duo-tec, EcoBlue, Megaflo, Assure, Main Eco and original 600/800. Codes can differ between models, so check your manual.

What E110 means on each Baxi model

From Baxi's own fault tables. Your model name is usually on the front of the boiler or in the user manual.

Model	Meaning	Causes listed for engineers
Platinum, Duo-tec, EcoBlue, Megaflo, Assure, Main Eco and original 600/800	Boiler maximum temperature exceeded for gradient, or safety thermostat sensor tripped	Probably the pump is jammed or there is air in the circuit