As a homeowner, you own it to your house and family to be at least a bit knowledgeable about DIY home maintenance. That includes knowing how to inspect your boiler’s situation.

Your boiler will stop working if something goes wrong with it. When this happens, most modern boilers will display an error code. Before turning it off, write down the trouble code and make sure any other gas appliances are working properly. If not, it’s possible that there’s an issue with the gas supply.

To determine the problem with your damaged boiler, use the following checklist.

Assess the Power Supply

  • Fuse box: First, check to see whether a switch in your fuse box has tripped, as this could affect your boiler. If you’ve recently experienced a power outage, your boiler’s timer may have reset. 

Verify that the time displayed on the clock corresponds to the current time. It’s time to reprogramme if it doesn’t. The essential instructions are normally found in the programmer handbook. If you don’t have a physical copy, finding one online is usually an alternative.

  • Prepaid metre: If you have a prepaid metre, running out of credit will turn off your power and force your boiler to shut down.
  • Ignition lead: Your boiler’s ignition is dependent on the ignition lead. If you hear clicking noises when trying to light your boiler, it could be due to a broken ignition lead or electrode. A specialist can test and replace these parts at a reasonable price.

Check the Gas Supply

  • Gas valve: A issue with the gas flow into your boiler is one of the most typical reasons why your boiler fails to ignite. There could be a clog or damage obstructing the passage of gas.

Check other gas appliances for proper operation, and make sure the Emergency Control Valve at the gas metre hasn’t been accidentally turned off. 

  • Gas pressure: Uneven gas levels in your boiler might cause problems. If the gas pressure is incorrect, your boiler will most likely display a problem code. You may call a specialist to help you test the gas pressure throughout your system.

Check the Pressure in the Boiler

A boiler will struggle to ignite if the water pressure is too low. If this is the case, inspect the pressure gauge or the boiler display. A water pressure of one to two bars is recommended. If it’s less than one bar, the water pressure is too low.

Following the directions in the boiler manual, you might try to repressurise the boiler. You may be able to get your boiler handbook online if you can’t find it.

Examine the Thermostat

Set your thermostat above room temperature, and turn on your central heating program. If a timer controls the system, the clock may have moved ahead or backward and has to be adjusted.

Make Sure There Are No Frozen Pipes

Because of the UK’s chilly environment, it’s very usual for the weather to damage your pipe system, and frozen condensation can easily produce a blockage. This blockage might cause the boiler to overflow, resulting in a breakdown.

You can try pouring warm water down the pipe’s end before turning the boiler on and off.

Check If the Pilot Light Is On

On older boilers, pilot light is more prevalent, and it might go out for various causes. You can try to switch on the pilot light on your own by following the directions in your boiler manual or on the inside of the boiler door.

Remember that you should never attempt to dismantle or modify your boiler. Contact a specialist if you can’t relight the pilot light using the manual.


You could suffer weeks of pain and discomfort while your boiler is out of commission. If you have a commercial space, you could lose days of vital commerce. 

As a quick solution, try looking for a boiler rental that can provide you with a cost-effective, quick-response installation that allows you to go back to business as usual. This should be enough until you can find a specialist who can repair your boiler.

If you need a boiler rental company in London, you can trust London Climate to deliver. We’re HVAC specialists, providing boiler chillers, heaters, portable air-conditioning, generators, and ancillaries. Contact us today to get a quote.