Unfortunately, complete boiler failure is a common problem. Causes can vary wildly from a crack in one of the boiler's cast iron (or aluminium) sections to a broken seal on the boiler pump. So we’ve outlined some common problems and advice on how to get your boiler up and running again.
Power supply
Is the power supply on? If not, you’ll need to contact your electricity supplier.
Gas supply
Is the boiler gas supply on? If the gas stopcock is on but no gas is coming through, you have a gas supply problem and need to call your gas supplier. If you have an oil boiler check there's enough oil in the tank by reading the gauge.
Pilot light
Is the pilot light igniting? If the pilot light has gone out you may be able to relight it by following the manufacturer's instructions. These are often printed on the boiler door, near to the pilot light, the front panel or in your boiler instruction booklet. You’ll need to:
- Check whether the gas stopcock is open or not.
- If it’s not, turning it on will solve the problem by restoring gas supply.
- If it is already open and there’s no gas coming through the stopcock then you have a gas supply problem and will need to call in a professional to complete the repair.
If your boiler model doesn't have a pilot light, press the de-blocking button. If that doesn't work, check the central heating pressure is set to the manufacturer's instructions (generally one bar). If that also doesn’t work (and the central heating pressure is correct), you either have a gas supply problem (contact your gas supplier) or you'll need to get an approved professional in for a repair.
Remember, you should never attempt to dismantle your boiler or alter it in any way. If you can't relight the pilot light then you’ll have to call out an approved engineer.
Central heating thermostat and boiler levels
Is the central heating programmer in the 'on' position? Try increasing the level of your boiler or central heating thermostat. The boiler will only work when the thermostat is set higher than the room temperature.
Central heating timer
Check that the timer on your central heating controls works and is set correctly. If it won't switch on you may have flat batteries or a problem with the power source.
Central heating pressure
Is the central heating pressure correct? Check that it’s set to the manufacturer's instructions (generally one bar). If it is, you either have a gas supply problem and will need to contact your gas supplier or a Gas Safe Register professional.
Condensate pipe
A condensate pipe carries condensation from your boiler to your outside drain. During extremely cold weather the condensation in this pipe may freeze and cause a blockage causing the condensate to 'back up' into the boiler and cause a shutdown.
Signs that the condensate pipe may have frozen include your boiler's display showing a 'fault code' or warning light as well as gurgling or bubbling sounds coming from the boiler or the condensate pipe.
If you suspect this is the problem, our handy guide on how to defrost a condensate pipe should get your boiler working again in no time.
Important information regarding our DIY help and advice
We try to make the advice on our website (www.HomeServe.com) as useful and reliable as possible. However, the purpose of this advice section of the website is to provide homeowners and private landlords with general guidance and useful tips only. It doesn't necessarily deal with every important topic or cover every aspect of the topics with which it deals and might not be relevant or appropriate in all circumstances. It is not designed to provide professional advice or financial advice and should not be relied on as such. Click here to read the disclaimer in full.