Why does my boiler keep turning off?
Is this a question you’ve been asking yourself? The following tips might help you find out what is wrong with the appliance, but we wouldn’t advise you to try to repair it unless you have the required competencies and qualifications. It is actually illegalfor unregistered people to work on gas appliances, flues and fittings, even if they own the defective property.
Low water pressure
Perhaps your boiler is leaking? Or maybe there is a leak elsewhere in the house? Perhaps you need to sporadically repressurise your boiler? If this isn’t the case, you might have a faulty pressure relief valve, and will need to get an engineer to replace it.
Thermostat problems
If your thermostat has broken, your boiler will not be able to recognise the temperature of the water, and it will shut itself off in order to prevent the appliance from overheating or because it assumes it has already reached the required temperature. You will need to replace your thermostat – you could save money by purchasing a newer thermostat, as this may reduce your energy bills in the long-term.
Your heat exchanger may have also broken. You will need to get this replaced, as it may be dangerous especially if the boiler keeps turning on and off.

Gas boiler keeps turning on and off? Run through these simple diagnostics before calling an engineer.
Lack of water flow
If the boiler keeps shutting off, it could be due to closed valves, air caught in the system or a broken pump. The boiler is switching itself off due to in-built safety mechanisms – if it did not shut down, then the boiler could overheat.
- If there is air in the system, then bleeding your radiators could resolve the problem. Check to see if your radiators are as warm as they should be – if some of them seem cold, bleed it. If there is enough air in the system to cause your boiler to switch itself off, it should be obvious when you start bleeding your radiators, as plenty of air will gush out of them.
- A closed valve can also prevent water from flowing properly within the boiler. Check the valves on the underside of the boiler – you may have closed one accidentally. However, the broken valve may be inside the boiler, in which case you will be unable to fix it if you are not Gas Safe Registered.
- You will be unable to repair a broken boiler pump yourself, and will need to contact an engineer.
Ensure you get all your gas appliances checked annually using a Gas Safe registered engineer. 24|7 Home Rescue work with over 3000 Gas Safe registered engineers and can cover a number of things from a boiler breakdown to a boiler service and even appliance repairs. Contact us today for more information.
Still no luck?
Don’t attempt to touch any part of your boiler or central heating system if you’re unsure. Did you know? It’s illegal for anyone to use a gas appliance if they think it’s unsafe. It’s always better to be safe than sorry as you could make things worse.
Instead, call us on 0345 3192 247 and we can help. Our technical team will run through some simple troubleshooting to see if your problem can be resolved on the phone or they can book one of our friendly and knowledgeable Gas Safe registered engineers to get you back up and running as soon as possible.
247 Home Rescue accepts no liability for any injuries or damages you sustain following the advice on this website. If in doubt, seek professional assistance.