A powerflush is a cleansing process which aims to remove deposits of sludge, rust and any other debris from your central heating system. These contaminants, if left, can seriously affect the efficiency of a heating system and in severe cases a powerflush is the only option available.
These systems are far more complicated, and have many more parts to them but do allow near mains pressure hot water supply. They are designed to do away with the storage cistern and operate at a much higher pressure than the open vented system here.
Combi boilers are designed to provide instant hot water, as well as heating the central heating system. Combi, or combination boilers, are the UK's most popular type of boiler. They can be an economical option, as combi boilers only heat the water you use.
Your hot water and central heating are entirely reliant on your boiler, making it the nerve centre of your home. It's important to check that your boiler is fully functional to keep you and your home warm throughout winter.