Boiler Reset Button Not Working?
Pressed reset but the boiler still will not fire, keeps flashing or goes straight back into lockout?
A reset button does not repair the original fault. It only asks the boiler to try its startup sequence again. If pressure, ignition, flame detection, condensate drainage or another safety check is still wrong, the boiler may refuse to restart.
This page is specifically for boilers that will not reset or reset and immediately lock out again. If yours starts normally and then cuts out later, use our boiler keeps switching off guide instead.
MPS Heating & Plumbing LTD diagnoses boiler reset faults across Croydon, Thornton Heath, Addiscombe, Norbury, South Croydon, West Croydon, Selhurst and East Croydon. Gas Safe Registered — ID 662170.
If one safe reset has not worked, call 0203 576 6769 and tell us the boiler make, fault code and pressure reading.
Qualified, registered and ready to help
Clear credentials displayed early, without distracting from the boiler fault advice or booking buttons.
Do not keep forcing a boiler out of lockout
One reset may be reasonable. Repeated resets usually mean the original fault is still active.
Diagnosis
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What It Means When The Boiler Will Not Reset
Modern boilers enter lockout when a safety check fails. Pressing reset clears the lockout temporarily and asks the boiler to try again.
If the fault is still present, the boiler may do nothing, flash the reset light, begin its ignition sequence and stop, or restart briefly before showing the same fault code again.
Low pressure, ignition faults, flame-sensing faults, blocked condensate pipes, overheating and circulation problems can all stop the reset sequence.
If the boiler is completely dead, see boiler not turning on. If you still have heating but no hot water, see no hot water but heating.
What Happens When You Press Reset?
| What The Boiler Does | What It May Point To |
|---|---|
| Nothing happens | Power, fuse, wiring, display or control-board faults may be involved. |
| The reset light keeps flashing | The original pressure, ignition, overheating or condensate fault may still be active. |
| The fan starts but the boiler does not ignite | Ignition electrodes, gas valve or flame-detection checks may be failing. |
| The boiler fires then locks out again | The startup sequence began, but the boiler detected the same fault again. |
| The boiler resets but pressure falls again | A leak, expansion-vessel fault or pressure-relief-valve issue may be present. |
Safe Checks Before Calling
Check the pressure gauge. Many sealed systems sit around 1 to 1.5 bar when cold, although the correct range depends on the boiler.
Check the boiler has power and the thermostat is asking for heat. If the controls are not connecting, read our thermostat not communicating guide.
During freezing weather, listen for gurgling and check whether an outside condensate pipe may be frozen.
Do not remove the casing, adjust gas parts or keep pressing reset repeatedly. If you smell gas or hear unusual ignition bangs, stop using the boiler and get urgent help.
Low Pressure
If topping up restores the boiler but pressure drops again, see our boiler losing pressure guide. The reset button is not the real fault.
Ignition Or Flame Fault
If the boiler clicks, attempts to light and locks out, the issue may involve electrodes, flame sensing, the gas valve or another gas-side component.
Overheating Or Circulation
A boiler may reset initially but lock out again if heat cannot move through the system properly because of pump, sludge, air or pressure problems.
Reset Fault Versus Boiler Switching Off
A reset fault means the boiler is already in lockout and will not complete the restart sequence.
A boiler that keeps switching off usually starts and runs before cutting out later because of overheating, circulation, pressure or controls.
If it fires normally and stops after a few minutes, use our boiler keeps switching off in Croydon page. That separation keeps the intent of both pages clear.
No Guesswork
We check the displayed fault, pressure, ignition sequence, flame detection, condensate route and whether the boiler is overheating.
Straight Advice
If the boiler needs fault diagnosis rather than routine servicing, we will say that clearly.
Local Experience
We diagnose Worcester Bosch, Vaillant, Ideal and Baxi lockout faults across Croydon and nearby South London.
Boiler Still Refusing To Reset?
Call 0203 576 6769 and tell us the boiler make, pressure reading, fault code and exactly what happens when reset is pressed.
If you have completely lost heating or hot water, see Emergency Boiler Service Croydon. For wider fault help, visit Boiler Repairs Croydon.
Boiler Reset Button Not Working FAQs
Why is my boiler reset button flashing or not working?
The boiler can usually still detect the original fault. The reset button may work, but the boiler will not restart while pressure, ignition, overheating, condensate or another safety problem remains active.
Is it safe to keep pressing the boiler reset button?
No. One reset may be reasonable if the manual says it is safe. If the boiler keeps locking out, stop repeatedly resetting it and get the fault checked.
Can low pressure stop a boiler from resetting?
Yes. Many boilers refuse to fire when system pressure is too low. If pressure keeps dropping after topping up, there may be a leak or expansion-vessel fault.
Why does my boiler reset and then go back into lockout?
The boiler attempted another startup sequence but detected the same fault again. Ignition, flame detection, pressure, overheating and condensate problems are common possibilities.
What should I tell the engineer?
Give the boiler make and model, any fault code, the pressure reading and exactly what happens when reset is pressed.
Do I need an emergency boiler repair?
If you have no heating or hot water, the boiler will not reset, there is a gas smell or another safety concern, urgent boiler repair advice is sensible.