Pros and Cons of Combi Boilers and Conventional Boilers

In this article, we aim to explore what combi and conventional boilers are, as well as the perks and negative effects that they can have on households and bill payers. In recent articles, we’ve discussed the merits of turning off the boiler in the summer, as well as putting together an essential guide to efficient water heating, but here we aim to look objectively at these two different boiler types in detail.

So without further delay, here are the pros and cons of combi boilers and conventional boilers…

What is a combi boiler?

Combi is short for combination, signifying the combination of both a high-efficiency water heater, and a central heating boiler system into the same unit. When you run the hot water tap, it gets directly heated by the mains, so you don’t need a hot (or cold) water storage tank in your attic.

These are arguably more cost and space effective than conventional boilers, as water is heated instantly, rather than being heated and then needing to be stored. Hot water is delivered at the same pressure as the mains with a combi boiler, meaning you can have a powerful hot shower; something which is often not possible with a conventional boiler, unless you have a separate pump.

What is a conventional boiler?

Sometimes you might see these boilers called traditional, heat-only or regular boilers, but they are all pretty much the same thing. For older properties, these are generally preferred, as the whole system is fitted into the design of the home, and combi boilers are a newer concept.

Conventional boilers are hooked up to a traditional heating and hot water system, as well as two water tanks, one for hot and one for cold water, which are both stored in the loft. If you have a traditional boiler, and it happens to break down, it’s recommended that you don’t upgrade to a combi boiler, as it would be too much of a challenge for your system, due to the higher water pressure requirements.

Pros and cons of combi boilers and conventional boilers

Combi Boiler Pros

• Compact sizes make more sense in small properties, where space is limited
• If there is no loft, combi boilers are a better option
• Less pipework in home
• More suitable for new-build properties
• Better energy efficiency

Conventional boiler pros

• Better for older buildings
• Perfect for larger or multiple-occupancy buildings, where a lot of hot water is used
• Homes with multiple bathrooms would be better served by a conventional boiler
• Good option for low water pressure areas
• Possible to combine with a solar water heating system

Cons of Combi Boilers

• Requires good mains water pressure
• Can only run one hot tap at a time
• Shower power is decided by water pressure
• If the combi boiler breaks down, you will have no access to hot water, as there is no backup immersion heater

Cons of conventional boilers

• Huge amount of space required
• Poor for energy efficiency, especially if tanks are poorly insulated
• You can only use as much hot water as there is available in the tank
• The water pump and heating systems are separate, requiring additional space

Conclusion

Feeling a bit clearer on which option is best for you? The average person isn’t expected to know about boilers, which is why we do our best to provide you with the valuable information that may help your future purchasing decisions. It’s important to know the difference between what you need, and what someone is trying to sell you. In this case, it’s important to know the pros and cons of combi boilers and conventional boilers, before you press ahead with this project.