It’s one of the most important decisions homeowners need to make for their homes: choosing between a combi boiler versus conventional boiler. With energy prices continually rising and there being greater pressure on efficiency, understanding the real cost implications of your heating system choice has never been more important.
The short version is that combi boilers tend to be less expensive to run than conventional boilers, with potential savings of 30% per year on the heating bill. For an average UK home, that adds up to a saving of approximately £250-£550 annually, with some homes saving up to £900 annually when fitted with an A-rated combi boiler.
Understanding the Key Differences
Prior to delving into running expenses, it is important to know that these two systems operate fundamentally differently. Combi boilers warm water on demand directly off the mains supply, instantly offering heating and hot water simultaneously without needing a dedicated storage tank. This space-saving, single-unit solution makes them perfect for smaller residences with little extra space.
Conventional boilers, or standard/heat-only boilers, are suitable to use with an independent hot water cylinder and cold water storage cistern. They heat up the water beforehand so it is ready for use later on, and therefore they are better for larger homes with more bathrooms where there may be several taps running simultaneously.
Running Costs
Even though we are talking running costs, the initial expense is what sets the foundation for ongoing costs. Combi boilers are between £1,600 – £6,000 installed while conventional boilers cost between £1,600 – £5,500 installed.
Replacing conventional with combi will be around £2,500-£4,000 since extra work has to be carried out to remove existing tanks and cylinders.
If you are eligible for a free A-rated combi boiler under the ECO4 scheme, then the whole process is done completely for free. Fill in our simple 1-minute eligibility form and find out if you qualify for free heating upgrades today!
Based on current UK energy prices, here are what you can pay for monthly running costs:
- Gas combi boiler: Around £120 per month
- Electric combi boiler: Around £206 per month
- Conventional boiler systems: Generally 20-30% more than comparable combi systems
Why Combi Boilers Cost Less to Run
The combi boiler vs standard boiler operating costs’ will depend on several key considerations:
1. On-Demand Heating
Combi boilers heat water only when you need it, eliminating the energy wasted as a tank of water needs to be maintained hot at all times. This can save energy by up to 20-30% over older traditional systems.
2. No Heat Loss
Old boilers are prone to standing losses where stored warm water gradually loses heat even in highly-insulated cylinders. That’s just paying to heat already hot water.
3. Higher Efficiency Ratings
New combi boilers enjoy 90-99% efficiency ratings, meaning almost all of the energy you’re paying for goes into heating your home and water. A-rated combi boilers can save up to 30% on annual energy bills compared to older ones.
Why Homeowners Choose Combi Boiler Over Traditional Boilers:
- Higher Running Costs
Standing heat losses and being less efficient make them more expensive to run.
- Space Required
Space required for hot water cylinder and cold water tank.
- No Instant Hot Water
Have extended wait time for the cylinder to refill and heat after excessive use.
- More Complex Installation
Requires more parts and pipework.
ECO Boiler Grants
The ECO4 scheme is an important support to homeowners who live in fuel poverty and need financial support in order to get their heating systems upgraded, to be able to live healthier, warmer and more comfortable lives. ECO Boiler Grants has supported thousands of homeowners in getting free heating system upgrades through the ECO4 scheme, including free A-rated boilers from premium brands like Worcester Bosch, as well as free insulation and radiators.
Our experienced team takes care of the whole application process, supporting you in every step of the way to ensure you are able to access the highest amount of funding available to you. All our installers are Gas-Safe registered, and we only use the highest quality materials and systems with 10+ years of warranty to give you peace of mind and increase your savings.
Fill in our simple 1-minute eligibility form and take a step towards a healthier home or contact us to learn more.
