Choosing the right combi boiler for your home is essential for efficiency, comfort, and cost-effectiveness. If you live in a three-bedroom house, selecting the correct kilowatt (kW) output ensures your home stays warm and your hot water supply meets demand. But how do you determine the right size? In this guide, we’ll break down the key considerations and help you make an informed decision.

Understanding Combi Boiler kW Ratings

The kW rating of a combi boiler refers to its power output. A higher rating means more heating capacity, which is crucial for larger homes with greater demand for heating and hot water. For a three-bedroom house, the ideal kW rating depends on factors such as:

• Number of radiators – More radiators require a more powerful boiler.
• Hot water demand – Households with multiple bathrooms need a higher kW output.
• Home insulation – Well-insulated homes retain heat better, reducing the need for a higher output boiler.

Most three-bedroom homes typically require a combi boiler between 24kW and 30kW, depending on the specific household’s needs.

Choosing the Right kW Output

Here’s a general guide to help you choose the best size for your home:

24kW – 26kW

• Suitable for homes with up to 10 radiators
• Ideal if you have one bathroom
• Best for smaller three-bed properties or well-insulated homes

28kW – 30kW

• Suitable for homes with up to 15 radiators
• Ideal if you have two bathrooms or an en-suite shower room
• Provides a stronger hot water flow rate

If you have a larger home or higher hot water demand, you may even need a 35kW boiler, but this is rare for a standard three-bedroom house.

Additional Considerations

Before settling on a combi boiler, consider the following:

1. Water Pressure and Flow Rate

Combi boilers heat water on demand, meaning your mains water pressure affects performance. If your home has low water pressure, a larger boiler won’t necessarily improve the situation.

2. Energy Efficiency

Modern combi boilers are highly efficient, with ratings of 90% or higher. Choosing an A-rated boiler can help lower your energy bills.

3. Future-Proofing Your Home

If you’re planning home extensions or additional bathrooms, opting for a slightly higher kW boiler might be a wise decision.

Expert Boiler Installation Advice

Choosing the right boiler is just the first step – ensuring a professional boiler installation is key to its efficiency and longevity. At T Griffin Plumbing and Heating, we specialise in installing high-quality combi boilers in Bognor Regis and the surrounding areas tailored to your home’s specific needs. Our experienced heating engineers can assess your property and recommend the best option for your household.

Need expert advice? Contact T Griffin Plumbing and Heating today for a free consultation!