Combi Boiler vs. Conventional Boiler: Which is Cheaper to Run?

With energy suppliers putting their energy prices through the roof, households are spending more money than ever on gas and electricity. This means that more people are looking for cost-effective ways to reduce energy expenditure and save them extra pennies when the heating is on.

The most popular boiler systems for most modern households in the UK are the combi boiler and the conventional boiler. Installing either system to your household offer different benefits that can help you save money on your household.

But, which is the cheaper option to help you save money on boiler running costs; the combi boiler, or the conventional boiler?

We look at the main differences between the two and break down some of the costs so you can make the right decision to cut those energy bills.

What are the main differences between combi and conventional boilers?

The conventional boiler has been a popular option for households in the UK since the introduction of central heating during the 1950’s.

Often preferred in larger households, the conventional boiler has many benefits that make it ideal for busy households, with often multiple persons using hot water at once.

Whilst conventional boilers have been found in many households around the UK, in recent years the combi boiler has increased in popularity.

The combi boiler system has many benefits for households that are more reserved with their energy usage and only want to heat their home in small doses.

Boiler Comparison: Combi vs. Conventional

Combi Boiler

Conventional Boiler

Combi Boiler

Heats on Demand
Meet One Hot Water Demand
Smaller, Compact Systems
Compatible with Modern, Smart Boiler Technology

Conventional Boiler

Reserve Hot Water Supply
Meet Multiple Hot Water Demands
Uses Up Large Amount of Space
Old School Boiler Trickery

Which is cheaper: the combi or the conventional boiler?

The results are in… for the average UK household, combi boilers are more cost effective for energy usage. According to reports, the combi boiler can save you between 25-30% on your monthly energy bills when installing one in your home.

Why is this the case you ask?

Combi boilers are designed to meet small household demands, rather than reserve hot water supplies for you, and save energy usage when not needed. See it as rationing your energy usage by using up energy in small packets, as opposed to cooking a feast and being too stuffed to finish your plate.

Yes, conventional boilers are the more convenient boiler as they allow multiple hot water appliances to run and help you in the emergency case that your boiler breaks. However, it is not as cost effective for smaller households that are willing to put up with reduced energy usage, to avoid unnecessary spending.

What Makes Conventional Boilers More Expensive to Run?

The conventional boiler uses a lot more complex system than the combi boiler, which means that it does cost more money to run for the average household.

Unlike the combi boiler, which is just attached to your mains water and hot water appliances throughout your home, the conventional boiler has two cold water storage tanks and a hot water cylinder which provides a hot water reserve. This is useful for homes that have larger hot water demands and provides an option if there is an emergency breakdown and want a hot shower before work!

Heating water, even when there isn’t instant demand means that more energy is being used, will be more costly to run over time.

Smart Boilers Helps Cut Running Costs

Modern combi boilers are compatible with smart thermostat technology which means that you have full control of your boiler usage.

Now you can choose how warm you want your home to be, set alarms for when you want your boiler to be turned on and off, choose how long you want it to be turned on for and you have the ability to turn it off if you’ve dashed out and forgot to switch it off.

Gaining control over your energy expenditure with a smart boiler helps reduce your usage each month and save hundreds of pounds a year on your running costs.

What Smart Technologies are Available for Combi Boilers?

Hive Smart Thermostat Controls

Hive are one of the leading smart thermostat controls on the market, with simple controls and cutting edge technology making it a popular feature for smart boilers for households in the UK.

Main features:

Geolocation – get instant alerts if you’ve left the house and left the heating on
Holiday mode – active holiday mode so your heating is not on whilst away, and ready for when you walk through the door
Smart controls and schedules – choose times and dates that you want the heating to turn on automatically
Heating history – track when you’ve had the heating on and how long

The Hive thermostat is retailed at around £119 on the Hive website.

Nest Thermostat Controls

Nest is another of the leading smart thermostat controls on the market, with adaptive technology that learns your heating behaviours and uses scheduling to suit your lifestyle. Owned by Google, the Nest claims that it ‘better than smart’, giving you more control over your central heating as well as your hot water tank.

Main features:

Smart home integration with Google Assistant and Alexa
Heating adjustment based on heating behaviours
Reports on heating usage and suggestions for saving energy in the future
Weather understanding technology and responds to outside temperatures

The Google Nest thermostat is retailed from £150+, depending on the generation you choose.