A small system boiler is a type of boiler that is specifically designed to provide hot water and central heating to a small home or apartment. Unlike a traditional boiler, a small system boiler does not require a large storage tank, and instead, is designed to provide hot water on demand. This makes it an ideal choice for those living in smaller spaces, as it can provide hot water without taking up too much space. Small system boilers are typically more efficient than traditional boilers, as they do not require a large storage tank, and therefore, use less energy. Additionally, they are usually easier to install and maintain, as they are smaller and require less space. As a result, small system boilers are becoming increasingly popular for those living in smaller homes and apartments.