Which hot water system do I have

Gravity fed/Unpressurised System – These systems require a separate hot water tank, usually found in the loft or cupboard. If you have a hot water tank then you most likely have a Gravity fed/Unpressurised hot water system.

Combi Boiler/Pressurised System – These system do not use a feed tank or hot water tank. If you do not have a hot water tank then you most likely have a Combi Boiler/Megaflow Pressurised System hot water system