Combi, heat-only and system boilers
There are typically three types of gas boiler to choose from: combination (combi), heat-only (also called conventional or regular) and system boilers.
Combi boilers provide hot water on demand. Best suited for small flats or homes, with low water demands (eg one bathroom).
Heat-only (regular) boilers require a cold water feed tank and hot water storage tank, usually installed in the loft. Best suited for larger homes with a high water demand (eg multiple bathrooms being used at the same time).
System boilers are like regular boilers, but don't require a cold water feed tank and have more parts built into the boiler body. Best suited for larger homes with poor water pressure and a high water demand.
Your heating engineer will be able to talk you through the different types and make a recommendation to suit your needs.
Learn more about the pros and cons in our different types of boiler guide. - https://www.which.co.uk/reviews/boilers/article/buying-a-new-boiler/what-are-the-different-types-of-boiler-a0Fpc4I2M9Fk