Changing from Conventional Boiler to Combi Boiler

The most effective way of upgrading the heating system in your home is to replace a conventional boiler to a combi boiler. By removing the need for a hot water cylinder and cold-water storage tank, a combi boiler can free up valuable space while providing hot water whenever you need it. Here, you will get to know how the conversion works, what to expect during the process, and whether switching to a combi boiler is the right choice for your home.

What Is the Difference Between a Conventional and Combi Boiler?

The main differences between a conventional and combi boiler come down to storage, space, water supply, and how hot water is delivered.

Why Switch from a Conventional Boiler to a Combi?

Switching from a conventional boiler to a combi boiler provides several benefits to many UK households.

Space: removing the cylinder and cold-water tank frees an entire airing cupboard and clears the loft

Efficiency: Modern condensing boilers achieve efficiency rates of over 90%, while older non-condensing gas boilers often operate at 60% efficiency, meaning a significant amount of energy is wasted. Find out boiler efficiency

Convenience: Hot water is available on demand, without needing to wait for a cylinder to reheat.

Simpler system: fewer components, fewer points of failure.

How Much Does It Cost to Replace a Conventional Boiler with a Combi?

The cost of replacing a conventional boiler with a combi in the UK typically ranges from £2,500 to £4,500. This will depend on the boiler size, type and model, the complexity of the installation, whether the boiler is being relocated, and the labour charges. For a full breakdown of costs, visit our new boiler cost guide. When replacing a water tank system, the removal of the old water tank and cylinder is typically part of a complete conversion quote, so be sure to request an itemised quote before committing.

Does a Combi Boiler Save Money on Energy Bills?

A combi boiler can reduce your heating costs as it will only heat water when required instead of using a separate hot water cylinder which would be heated continuously. This helps to keep energy waste to a minimum and can enhance overall heating system efficiency.

Depending on the quality of insulation in your house, its use, and the type of boiler, you may be able to save on energy bills by reducing energy loss. While these costs are very different for each home, many people have been able to save money on their running costs when they install a new combi boiler. According to the Energy Saving Trust, replacing an old G-rated boiler with a new A-rated condensing combi boiler can significantly reduce your home’s energy bills.

The Conversion Process from Conventional to a Combi Boiler

The conversion process usually takes one to two days, but it can take longer if the installation is more complex. This is done by removing the old boiler, hot water cylinder, and cold-water tank, making the necessary pipework adjustments and then fitting the new combi boiler.

Once installed, the system is flushed to remove sludge and debris from the heating system, and the system is then tested and commissioned with the new boiler. Installation should only be carried out by a Gas Safe registered engineer, and the Building Control should be notified for the installation to comply with the requirements of the Gas Safety (Installation and Use) Regulations 1998.

When Should You Switch from a Conventional Boiler to a Combi?

If your conventional boiler is showing any of the following signs, it may be time to consider a replacement:

• Your boiler is becoming less efficient.
• Repair costs are increasing and becoming uneconomical; consider a boiler repair assessment before committing to a full replacement.
• Energy bills are rising without a change in usage.
• Heating or hot water has become unreliable.
• Your boiler breaks down more frequently.
• The flame is not blue, but yellow or orange. If this happens, seek advice from a Gas Safe registered engineer immediately.

If your boiler goes beyond economic repair, it’s usually best to install a new combi boiler in the long term. Adding a boiler cover and getting a boiler service once a year can help ensure your new boiler is operating safely and efficiently. Learn more about boiler lifespan.

Ready to Make the Switch

Upgrading from a conventional boiler to a combi boiler is an investment in your home heating system. If your current boiler is not performing effectively or is costly to maintain, switching to a combi boiler can be the right decision to enhance your home comfort and reduce energy bills.

At 24|7 StayWarm, our team can help you find the right combi boiler and carry out a professional new boiler installation. Get in touch today to discuss your options.

Boiler Insurance You Can Trust

Get boiler breakdown and landlord cover including free annual boiler service.

Choose your policy type

Get Boiler Cover Get Landlord Cover