Which Boiler Do I Need?
Combi, System or Regular?
It's a common question asked by our customers.
Combination or ‘Combi’ Gas boilers provide central heating and hot water on demand using mains fed water. There’s no need for a hot water cylinder, cold water tank or expansion tank. These are the most modern type of boilers and are popular in apartments where space is at a premium. You can find out more information about Combi boilers here.
System Gas or Oil boilers provide heating on demand using an unvented system under pressure, similar to Combi boilers. As the heating system is unvented there’s no need for an expansion tank. System boilers provide hot water by heating a hot water cylinder tank on a set schedule.
System boilers are a more traditional and common in houses where there is space in an attic for a cold water tank and an airing cupboard for the hot water cylinder. Find out more on how System boilers work.
Regular boilers are very similar to System boilers but use a unpressurised vented system for heating the radiators. This means in addition to a water tank and cylinder, Regular boiler systems require an expansion tank in the attic. Here’s more details on how Regular boilers work.