Boilers · Homeowner answer
Combi, system or regular boiler — which do I need?
Short answer
It depends on how much hot water you use at once. A combi heats water on demand and suits one bathroom. A system boiler with a cylinder suits two or more bathrooms in use together. A regular boiler with attic tanks is common in older houses and is usually replaced like-for-like unless there is a reason to change.
What changes the answer
- number of bathrooms and showers used at the same time
- mains water pressure and flow
- space for a cylinder
- whether a heat pump is likely in future
What you can check yourself
- count the showers that might run together on a busy morning
- check whether you have a cylinder in the hot press and tanks in the attic
What to do next
The Boiler Quote Builder asks these questions and suggests the likely type.
This page gives general information only. Christy needs to see your system — in person or from your photos — before he can give you firm advice or a price.