Error code
Baxi Boiler Fault Code E20
Quick answer
E20
A boiler sensor is giving an invalid reading
First safe action
Consult the manual for any user guidance specific to this fault.
Meaning
Baxi boiler fault code E20 usually means the boiler is receiving an unexpected reading from one of its temperature or system sensors.
Likely causes
- Faulty sensor
- Wiring issue
- Control board not interpreting the sensor correctly
Safe first checks
- Consult the manual for any user guidance specific to this fault.
- Use only the standard reset process if it is intended for homeowners.
- Stop if the code reappears immediately.
How to reset
- Carry out one standard user reset if the manual allows it.
- Arrange professional diagnosis if the sensor fault remains active.
When to call an engineer
If the code remains after one standard reset, a qualified heating engineer should inspect the boiler.
Safety warning
Do not remove the boiler casing or handle internal wiring or sensor components yourself.
Useful hub links
Related fault codes
E1 for Baxi Boiler
A boiler sensor is giving an invalid reading
E10 for Baxi Boiler
A boiler sensor is giving an invalid reading
E28 for Baxi Boiler
Condensate, drainage, or pump protection issue
E53 for Baxi Boiler
A boiler sensor is giving an invalid reading
133 for Baxi Boiler
The boiler has failed to ignite properly
E50 for Baxi Boiler
Control board or internal communication fault
Relevant guides
Frequently asked questions
Can I keep resetting a Baxi boiler with E20?+
No. If E20 returns after one standard user reset, stop there and arrange a qualified engineer if the manual gives no safe next step.
Is E20 something I can repair myself?+
Boiler faults should be treated cautiously. Stay within the user checks in the manual, and leave gas, combustion, and internal boiler repairs to a qualified professional.