Complete Guide to Combi Boilers 2025
Everything you need to know about combi boilers. Compare costs, efficiency, and find out if a combi boiler is right for your home.
What is a Combi Boiler?
A combi (combination) boiler is a compact unit that provides both heating and hot water on demand without needing a separate water tank. It heats water directly from the mains when you turn on a tap or heating system.
Pros and Cons of Combi Boilers
Advantages
- Space-saving design - no need for water tanks
- Instant hot water on demand
- Lower installation costs
- Good water pressure
- Energy efficient
- Easy to maintain
- Ideal for small homes
Disadvantages
- Limited hot water flow rate
- Not suitable for multiple bathrooms
- Reduced pressure with multiple taps
- Requires good mains water pressure
- No backup hot water if boiler fails
Popular Combi Boiler Brands
Worcester Bosch
Popular Models
94%
10 years
Vaillant
Popular Models
94%
10 years
Baxi
Popular Models
93%
10 years
Ideal
Popular Models
93%
10 years
Frequently Asked Questions
What is a combi boiler?
A combi (combination) boiler is a compact unit that provides both heating and hot water on demand without needing a separate water tank. It heats water directly from the mains when you turn on a tap or heating system.
How much does a combi boiler cost?
Combi boiler costs range from £1,500 to £3,500, depending on the brand and model. Installation typically costs £500-£1,000. Through the ECO4 scheme, eligible homeowners can get a free combi boiler installation.
How long does a combi boiler last?
A well-maintained combi boiler typically lasts 10-15 years. Regular servicing and proper maintenance can extend its lifespan. Most manufacturers offer warranties of 5-10 years.
Is a combi boiler suitable for my home?
Combi boilers are ideal for small to medium homes with 1-2 bathrooms. They're perfect for flats and houses where space is limited. However, they may not be suitable for homes with high hot water demand or low water pressure.
Ready to Upgrade Your Boiler?
Check if you qualify for a free combi boiler through the ECO4 scheme. Our experts will help you choose the right model for your home.