Pilot Light Gone Out On Your Boiler?
What to do when the pilot light goes out on a boiler — and when to stop relighting it.
Older gas boiler lost its flame? Don’t keep relighting it without knowing why
If your pilot light has gone out, the first thing is simple: do not keep forcing it back on. A lot of people search for how to relight a pilot light on a boiler safely, but repeated relighting without understanding the fault is where problems start. One careful relight, following the boiler instructions, is one thing. Doing it again and again is where people get caught out.
We still come across plenty of older boilers and failing pilot lights around Croydon, Thornton Heath, Addiscombe and Norbury. Some are tucked inside kitchen cupboards. Some are in cold little utility spaces by a back door. Some have just been sitting there for years with the same weak pilot flame nobody really looked at.
Sometimes the problem starts as a pilot fault before turning into a full boiler not turning on situation altogether, especially once ignition components start failing consistently.
Sometimes it is a worn thermocouple. Sometimes the pilot jet is dirty. Sometimes a draught is disturbing the flame. And sometimes the boiler is old enough that the gas safety side needs checking properly before anyone keeps relighting it.
MPS Heating & Plumbing LTD helps homeowners across Croydon, Selhurst, Addiscombe, Thornton Heath, South Croydon and nearby areas with older boiler faults, weak pilot flames, boiler breakdowns and gas boiler repairs. We currently have a 5.0 Google rating from 62 reviews.
If you smell gas, stop. Do not relight the boiler. Open windows, leave the property and call the National Gas Emergency Service. If there is no gas smell but the pilot keeps going out, call 0203 576 6769. If the flame will not stay lit or the boiler keeps shutting down, our Boiler Repairs Croydon service covers pilot, ignition and gas boiler faults.
Do not keep relighting a pilot flame that will not stay on
A weak, yellow, unstable or repeatedly failing pilot flame needs proper diagnosis rather than repeated resets.
ID 662170
62 Reviews
8am–2am
What It Usually Means When A Boiler Pilot Light Goes Out
On older boilers, the pilot light is the small flame that stays on in the background. It is there so the main burner can fire when the boiler calls for heating or hot water.
If it goes out once, especially after windy weather or after the boiler has been off for a while, it might not be a huge drama. But if the boiler pilot light keeps going out, there is nearly always a reason.
If the pilot light will not stay lit or the boiler continues shutting down, our boiler repairs in Croydon service can diagnose the underlying fault.
The thermocouple is a common one. It is a small safety part that proves the pilot flame is actually lit. When it gets weak, dirty, loose, or sits slightly away from the flame, the boiler can shut the gas off even after you have relit it.
Another one we see is a dirty pilot jet. The flame goes lazy. Not sharp. Sometimes it turns yellowish or starts flickering. It may light at first, sit there for a few minutes, then drop out when the boiler warms up.
Then there are the London house problems. Draughty cupboards. Old doors. Loose vents. Boiler boxed in too tightly. Around Croydon and Thornton Heath especially, we still see boilers sitting in awkward little spaces where the flame never gets a clean, steady chance.
If the pilot refuses to stay lit, it normally needs fault diagnosis first rather than routine servicing. Our boiler repair service in Croydon covers recurring pilot faults, thermocouple problems, ignition issues and other faults that stop the flame holding safely.
Common Reasons A Pilot Light Keeps Going Out
| Possible Cause | What It Can Mean |
|---|---|
| Weak thermocouple | The boiler cannot prove the pilot flame properly, so it shuts the gas off as a safety response. |
| Dirty or blocked pilot jet | The flame becomes too small, soft or uneven to hold properly. |
| Draught around the boiler | Cold air from doors, cupboards, vents or old gaps can disturb the pilot flame. |
| Gas valve or supply issue | If the flame is unstable or keeps failing, a Gas Safe engineer needs to test it properly. |
When You Should Stop Trying To Relight It
Relighting once, by the book, is different from nursing the boiler back to life every morning. In other cases, homeowners press reset repeatedly but the ignition sequence never properly restarts, which usually points to a deeper fault than a simple flame outage.
Stop trying if the flame is yellow or orange. Stop if it keeps dying after a few minutes. Stop if there are soot marks near the boiler, odd smells, banging sounds, dizziness, headaches or nausea in the property.
That is not the time to guess. It needs checking.
A proper engineer should not just press the button, get the flame back, and leave. They should be looking at the pilot assembly, thermocouple position, flame shape, burner area, ventilation and any signs around the flue or casing.
Sometimes it is a small fix. Sometimes the pilot fault is the warning sign that the older boiler is not proving flame safely anymore.
Simple Checks First
You can check whether the boiler has power, whether other gas appliances are working and whether the manual allows relighting. If the pilot will not stay lit after one safe attempt, stop there and make a note of what the flame does before booking a proper boiler fault check.
Usually More Than A Reset
If the gas boiler pilot light is not staying on, it is usually something around the thermocouple, pilot jet, draught, flame position or gas valve. Guessing does not help much here.
Older Boilers Still Around
We still see older Baxi, Ideal, Vaillant and Worcester Bosch boilers across Croydon and South London. Some are still worth repairing. Some are getting tired, and that needs saying honestly. A proper boiler repair diagnosis should establish whether the pilot fault is a sensible repair or a sign the boiler is becoming unreliable.
A Typical Callout We See Around Croydon
A common call goes like this. Someone in Thornton Heath, West Croydon or Selhurst wakes up, notices the house feels cold, checks the boiler and sees the pilot has gone out.
They relight it. It seems fine. Five or ten minutes later, it drops out again. Sometimes the pilot relights briefly before the boiler shuts itself down again, especially once the thermocouple starts struggling to hold the flame properly.
Sometimes the flame looks weak from the start. Sometimes the thermocouple has simply had enough after years of heat. Other times the pilot jet is partly blocked, so the flame cannot hold the safety device open properly.
If you are in Croydon, Addiscombe, Norbury, Selhurst or South Croydon and the pilot keeps disappearing, call 0203 576 6769. We will ask what boiler you have, whether there is any gas smell, what colour the flame is, and whether you still have heating or hot water.
No Guesswork
We check the flame condition, thermocouple response, burner area and visible safety signs instead of just relighting the boiler and hoping it behaves.
Straight Advice
If it is a small repair, we will say so. If the boiler is unsafe, unreliable or becoming poor value to keep patching up, we will explain that too. If repair work is needed, our Boiler Repairs Croydon service covers the diagnosis and repair of the underlying fault.
Local Boiler Experience
MPS Heating & Plumbing LTD is Gas Safe Registered — ID 662170. We work across Croydon and South London on older gas boiler faults and recurring pilot light problems.
What Happens Next
We have not put a fixed price here because pilot light faults are not all the same. One boiler might need a small part. Another may need gas-side testing before anyone can give proper advice.
Before any repair work starts, we explain what we have found, what the next step is, and whether spending money on that boiler still makes sense. If the boiler is becoming uneconomical to repair, we will explain that clearly before you spend money on it.
No scare tactics. No pretending every old boiler must be replaced. But no brushing off a safety fault as “probably fine” either.
What Customers Have Said
“Called because the old boiler pilot kept cutting out. They explained the safe checks first instead of trying to scare us into replacing the boiler.”
— Croydon customer“The engineer actually explained why the pilot would not stay lit instead of just resetting it and leaving.”
— Thornton Heath homeowner“Older boiler in a kitchen cupboard that kept losing the flame. Turned out to be a weak thermocouple and blocked pilot jet.”
— South Croydon customerPilot Light Gone Out In Croydon Or South London?
If the pilot has gone out once, it may be nothing serious. If it keeps going out, will not stay lit, or looks weak, get it checked rather than repeatedly relighting it.
Call us and we will ask a few plain questions first: what boiler you have, what colour the flame is, whether there is any smell of gas, and whether the heating or hot water is working.
Pilot Light Gone Out FAQs
Is it dangerous if my pilot light has gone out?
It can be. If you smell gas, do not relight it. Open windows, leave the property and call the gas emergency service. No smell of gas, but the pilot keeps going out? Get the boiler checked rather than forcing it back on.
Why does my boiler pilot light keep going out?
It could be a weak thermocouple, dirty pilot jet, draught, unstable flame, gas valve issue or simply an older appliance that has not been serviced properly for a while.
Can I relight the pilot light on my boiler myself?
Only if the boiler instructions say you can and there is no smell of gas. Do not remove the casing, adjust gas parts or keep trying if the flame will not stay on.
What colour should a pilot flame be?
Usually blue and steady. A yellow, orange, weak or flickering flame can mean dirt, poor combustion or another fault that needs checking.
Should I repair or replace the boiler?
It depends on the age, condition, parts availability and how often the fault comes back. A simple thermocouple fault may be worth repairing. An old boiler with repeated safety issues may not be.