How to Reset a Boiler UK: Step-by-Step Guide 2026
Resetting clears many lockout states after the underlying issue is fixed (such as restoring pressure). This guide covers safe reset steps for combi, system, and conventional UK boilers in 2026.
Safety First
If you smell gas or suspect a dangerous fault, do not reset—follow emergency guidance and call for help.
Typical Reset Procedure
Switch off, wait, fix safe issues like low pressure if applicable, then use the reset control per the manual—often a button or dial position.
By Boiler Type
Combi, system, and heat-only boilers differ in controls, but the principle is the same: clear the fault, reset once, observe behaviour.
If It Will Not Stay On
Repeated lockouts need professional diagnosis—avoid endless reset cycles.
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Use the Boiler Size CalculatorFrequently Asked Questions
How many times should I reset?
Try once after addressing safe basics; repeated lockouts need an engineer.
Where is the reset button?
Varies by model—check the boiler manual.
Will resetting fix a leak?
No—fix leaks and pressure issues first.
Does resetting clear error codes?
Sometimes temporarily—but underlying faults remain until repaired.
When should I call Gas Safe?
If lockouts repeat, you smell gas, or you are unsure—call a professional.