Unlike combi boilers, system boilers heat up water in advance. This is stored in your hot water cylinder ready for when you need it.
A big advantage to system boilers is that they can provide hot water at a good pressure to multiple outlets at the same time.
System boilers are also popular because they’re relatively compact, although they do take up more space than combi boilers.
Is the sealed system boiler right for me?
System boilers are great for homes with multiple bathrooms as they can supply multiple showers or taps with hot water at the same time. They’re also a great choice if you want a boiler that doesn’t take up too much space.
A system boiler will probably work well for you if you have a regular routine as you can set your boiler to heat water ready for when you need it. However, if you want hot water at different times on different days then a combi boiler might be better.