E.00.17Baxi
Baxi E.00.17: hot water tank temperature sensor short-circuited
Checked against Baxi's own documentation: Baxi: boiler error codes. Last reviewed October 2026. How we check
Engineer only
Baxi describes E.00.17 on Baxi Combi 2 and System 2 (200, 400, 600, 800, Assure 500) boilers as: hot water tank temperature sensor short-circuited.
What you can safely do
There is nothing you can safely do yourself with this one. Leave the boiler off and book an engineer.
Before you book an engineer
- Write down the code exactly as the display shows it: E.00.17.
- 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.
Call a Gas Safe engineer if
- Book a Gas Safe registered engineer.
Find a Gas Safe engineer near you
Opens the official Gas Safe Register search.
Applies to Baxi Combi 2 and System 2 (200, 400, 600, 800, Assure 500). Codes can differ between models, so check your manual.