What Is a Combi Boiler & Is It Right for Your Home?

Are you still scratching your head over which type of boiler will suit your home?

If you’re worried about energy efficiency and the cost of heating, a combination boiler (or combi) could be the perfect solution.

Read on to find out how they work, the pros and cons, and whether they are right for your property.

How combi boilers work

A combi boiler is an all-in-one heating solution.

It acts as both your central heating boiler and your hot water cylinder in one space-saving unit.

These systems are incredibly intuitive.

When you turn on a hot water tap, or your home’s temperature drops below your pre-set limit, the boiler automatically fires up.

Because there is no need for a cold water feed from a loft tank, a combi uses mains-fed water.

This means hot water is available 24/7 and is delivered directly at mains pressure. You won’t even need to install a pump for a powerful shower!

It also functions as a condensing boiler.

This means it turns exhaust gases into liquid condensation, reusing the latent heat that older, regular boilers would normally waste.

Is a combi boiler right for your home

Choosing the right boiler is essential to guarantee the correct flow of hot water and to keep your energy bills level.

Combi boilers are generally more suited to small to medium-sized properties.

They usually offer enough hot water for a shower and standard taps in a property with up to 3 bedrooms and two bathrooms.

1. Check your current layout

The most obvious way to tell if a combi is right for you is to look at your current central heating setup.

If you only have a boiler installed, with no loft tank or hot water cylinder, your current boiler is already a combi.

For a heating engineer, this is the easiest replacement as it’s a simple swap.

2. Check your mains pressure

Dependence on mains pressure can sometimes be an issue.

A combi boiler relies on your pressure being at an excellent level to function correctly and send hot water around your heating system.

If you currently have a cylinder but experience reduced water pressure when running taps, your mains pressure might be insufficient for a combination boiler to be installed.

Advantages of a combi boiler

Space-saving

A combi contains all its components within the boiler, completely eliminating the need for a bulky loft tank or hot water cylinder.

Lower heating bills

Combi systems are highly efficient A-rated boilers.

Upgrading could help save you up to £300 a year off your heating bills.

Unlimited hot water

You get heating and hot water right when you need it, meaning heat isn’t wasted and left to cool in a cylinder.

Easier maintenance

They require less pipework upon installation, which leads to easier maintenance down the line.

Disadvantages of combi boilers

One task at a time

Because combis are better suited to smaller homes, you’ll likely only be able to use hot water for one task at a time.

Someone washing up in the kitchen while you shower could cause hot water issues.

More moving parts

Due to their compact nature, there are more internal components packed inside.

This means there is the potential for more things to go wrong compared to a regular boiler.

No power showers

High-capacity power showers cannot be installed with these systems.

Not for large households

They cannot deliver high capacities of hot water to multiple bathrooms at once.

Combi boiler alternatives

If a combi isn’t quite right for your home, you might want to consider comparing other types:

Regular boilers

Conventional boilers (also known as regular or traditional boilers) require both a hot water cylinder and a loft tank.

They are a great choice for homes with multiple bathrooms, as they can provide large volumes of hot water to more than one faucet at a time.

System boilers

System boilers require a water cylinder but no loft tank.

Like regular boilers, they provide multiple taps with hot water simultaneously, but without taking up space in your loft.

Combi boilers worth considering

The Worcester Bosch Greenstar 25i boiler is a massively popular choice amongst UK consumers.

It is ideally suited to smaller flats and houses.

The Worcester Greenstar gas boiler range has even won the Which? Best Buy award for 7 years running due to its high efficiency, improved controls, and high-quality finish.

Gas Safe installation is a must

Please note: Combi boiler installation is relatively complicated.

It is vital that only a qualified, Gas Safe registered engineer is booked to install, maintain, or fix your domestic gas boiler.

An installation might involve a power flush of your pipes, new pipe installations, and the safe disposal of your old unit.

Taking boiler advice or boiler servicing from an unqualified engineer can invalidate your manufacturer warranty and could be incredibly dangerous.

Expert boiler advice from Hometree

Need boiler cover or advice on a new installation?

Get in touch with Hometree.