Should I turn off my boiler in the summer?

Is it ok to turn off your boiler in summer? The short answer is: it depends on your home and your circumstances.


If you have a modern, efficient combi-boiler, which provides heating to your home and hot water to your taps and shower, you’ll most likely still need to keep your boiler on all year round.


Many boilers have the option to keep the hot water on and the central heating off, which is useful for summer when you probably won’t need to have your radiators on for the most part. This option might be available on your digital display (if you have one) or as a dial or knob. If your boiler shows icons, hot water is usually depicted by an image of a tap, and heating by an image of a radiator. Set your boiler to just the tap icon if you don’t need your central heating on.


Some people don’t need hot water on constantly. This is true for people with:


  • Electric showers – cold water is heated by the shower itself
  • Modern dishwashers – no need for hot water, unlike when washing dishes at the sink
  • Modern washing machines – cold water is heated by the washing machine itself


It’s worth considering, however, that maintaining your hot water tank to at least 60°C will ensure that harmful bacteria in the water doesn’t multiply. Keeping your hot water at this temperature will reduce the risk of contracting legionnaire’s disease, and other nasty ailments.


Although you may be saving money by switching your boiler off, over time it may lead to problems. Your central heating system is complex and you will have several valves and pumps that are not designed to stay idle for long. Lack of usage might lead them to seize up and get stuck.


In order to keep your boiler in good shape, it’s worth turning it on every few weeks or so, and leaving on for a short while. Having the water flow freely stops the intricate insides of your system from getting ‘gunked up’ and prevents valves from sticking. This is especially true for older boilers, which need as much if not more care than modern, efficient condensing boilers.