How do you fix a boiler that won’t ignite?

Several issues can prevent a boiler from igniting, ranging from simple thermostat settings to more complex faults. Below, we’ll walk through the most common checks you can do at home before booking a boiler repair in Westminster.

Check if the thermostat setting is too low

One of the simplest reasons a boiler won’t fire up is that your thermostat has already reached its target temperature. For example, if the thermostat is set to 18°C but your home is already at 19°C, the boiler won’t turn on.

In this case, try raising the thermostat setting above the current temperature — for instance, set it to 20°C. If the boiler kicks in, you’ve solved the issue. Otherwise, you may want to check with a plumber in Earls Court.

 

 

Gas supply issues

 

Boilers rely on steady gas pressure to work properly, so your system may fail to ignite and even display a fault code if there’s little or no supply. To rule this out, check whether other gas appliances like your oven or hob are working. If they don’t turn on either, there might also be an issue with your supply. In that case, consider checking with your gas supplier before calling for boiler repair in Westminster.

 

 

Electrical issues

 

Boilers need electricity to ignite, so power problems can also be the culprit. Sometimes, a tripped fuse or a power cut can cause the system to reset. It’s worth checking your fuse box and making sure that your control panel settings are correct. If they’ve reset during an outage, reprogramming them may solve the problem. Not sure how to do that? You can always call the company that handled your boiler installation in London.

 

Issues within the boiler

 

In some cases, the problem lies inside the boiler itself. Faulty components, such as the gas valve or fan, could prevent ignition. These are usually problems that require a trained plumber in Earls Court to diagnose and fix.

 

 

Additional checks to try

 

Pilot light	Older boilers use a small flame called a pilot light. If it’s gone out, follow the manufacturer’s instructions to relight it. Keep in mind that most modern condensing boilers don’t have a pilot light, so this won’t apply to a newer model.
Thermostat	The thermostat tells the boiler when to heat. Your home may not reach the right temperature when the thermostat is not working correctly. Test it by turning the setting up and down to see whether the boiler reacts. If nothing changes, you may have found the problem. That’s your cue to call us for boiler repair in Westminster.
Pressure	Incorrect pressure can stop a boiler from firing, so check the gauge on the front of the unit to confirm. If it’s outside the recommended range, use the instructions in your boiler manual to correct it. After adjusting, reset the boiler and see if it ignites.
Frozen pipes	Even a small amount of frozen water in the pipes can block the system and stop the boiler from igniting, especially in cold flats in Brixton and Clapham. When this happens, the pipes need to be thawed before the boiler can start working again. The boiler should ignite again as soon as the ice clears.

 

 

When to call an engineer

 

Don’t try to repair internal boiler parts by yourself. Boilers involve high heat and gas, making them risky to fix without training. Insisting on going DIY on boiler repair in Westminster can cause serious injury and make the issue worse. It’s best to call a Gas Safe registered engineer to diagnose and repair the problem safely and properly.

 

Our Gas Safe registered heating engineers can quickly pinpoint why your boiler won’t ignite and fix the fault on the spot. At WPJ Heating, we handle everything from diagnostics to essential repairs and preventive checks, ensuring that your system runs reliably through the coldest months.

 

So, if you need a Gas Safe registered plumber in Earls Court or anywhere else in SW London, don’t hesitate to give us a ring at 020 7350 2511 to book an appointment.