Boiler Types – Combi, System & Regular

Different Boiler Types, Portsmouth

What is the difference in boiler types – combi, system and a regular gas boiler

The main differences between a combi (combination), system, and regular (conventional) gas boiler are related to their design, how they supply hot water, and their installation requirements.

Here’s a detailed comparison:

Combi Boilers

A combi (combination) boiler is a single compact unit that serves two purposes: it provides hot water for central heating and supplies hot water directly to taps and showers on demand.
It does not require a separate hot water storage cylinder or a cold water storage tank.

Advantages
Space-saving: Since it doesn’t need additional tanks or cylinders, it’s ideal for smaller homes or apartments.
Instant hot water: Provides hot water on demand, so there’s no waiting time for water to heat up.
Efficiency: Generally more efficient because it only heats water when necessary, reducing energy waste.

System Boilers

A system boiler heats water directly and stores it in a hot water cylinder. Unlike regular boilers, it doesn’t require a cold water storage tank as it takes water directly from the mains.
It incorporates some of the components found in a regular boiler, such as the pump and expansion vessel, within the unit itself.

Advantages
Consistent hot water: Can supply hot water to multiple outlets simultaneously without significant loss in pressure.
Compact: More compact than regular boilers as many components are built into the boiler itself.
Faster installation: Fewer external components make it quicker and easier to install compared to regular boilers.

Regular Boilers (Conventional Boilers)

Also known as traditional, conventional, or heat-only boilers, these systems use a separate hot water cylinder and a cold water storage tank, usually located in the loft.
They often require a feed and expansion tank as well.

Advantages
High hot water demand: Ideal for larger homes with multiple bathrooms as they can supply hot water to several outlets simultaneously.
Compatible with older heating systems: Often easier to integrate with existing radiators and pipework in older properties.

Choosing the right type of boiler depends on your specific needs, including the size of your home, your hot water usage patterns, and the space available for installation. Our experienced engineers can talk through your needs and help decide what boiler is best for you and your home. Contact us today for a quote!

Scroll to Top