There’s no universal best option when it comes to choosing a boiler, but many households opt for a combination (combi) boiler. Here are some advantages and disadvantages to consider.
Pros of installing a combi boiler
Space saving
The most visible advantage of having a combi boiler is the space it saves compared to a system or conventional boiler. For example, there’s no need for a hot-water cylinder or cold-water tanks, meaning you only need space for the boiler itself. If your old heating system has a hot-water cylinder, you may be able to reclaim the space and enlarge a bathroom or other room.
Instant hot water
The reason why a hot-water cylinder isn’t needed is because combi boilers provide hot water on demand. This means you always have access to hot water, whenever you need it and for as long as you need it. In comparison, other systems can only supply as much hot water as the cylinder can hold. This also can’t be replenished instantly, potentially leaving you with cold water in the middle of a shower.
Mains-fed cold water
Another potential benefit of combi boilers is that they are fed directly from the water mains. This means they derive the pressure to supply hot water to taps and showers from the mains alone. In contrast, a conventional hot-water system needs a cold-water tank, usually in a high place like the loft, to create pressure through gravity.
Energy efficiency
As combi boilers only heat water when it’s required, they can be more efficient for some households. This is because other systems fill a cylinder that even with good insulation will inevitably lose heat over time. Modern condensing boilers are also extremely efficient, with over 90% of energy typically being converted into home heating. This helps you stay warmer for less in winter.
Cost-effective installation
A heating system based around a combi boiler involves fewer elements, making the installation simpler and cheaper. There’s no need to install a hot-water cylinder or cold-water tanks, so there will also be no need for pipework to connect them.
Boiler modulation technology
A feature that you’ll find on modern combi boilers is modulation technology. What this essentially means is that the boiler can operate below its maximum output when appropriate. For example, as we get into spring, your heating needs to work less than it did in the depths of winter. Older boilers used to simply work at full power, powering off and on as required. Modulation technology enables boilers to work at a lower power but for longer periods to achieve the same result. This results in a cooler, more consistent system temperature with fewer starts and stops, helping components to function for longer.
Built-in WiFi
Having a combi boiler with integrated WiFi can provide the extra convenience of being able to control and monitor it from a smartphone. This may be especially useful when the boiler is installed in an out-of-the-way location. Such boilers may also communicate with other smart home devices.
Cons of installing a combi boiler
Combi boilers aren’t suitable for every household, and some disadvantages should be borne in mind.
Water pressure dependency
As mentioned above, combi boilers take advantage of the pressure from the mains. This works great when the mains pressure is adequate, but it can be a problem in low-pressure areas. In such cases, a different boiler type may be more suitable.
Limited hot water flow
As hot water is heated on demand, combi boilers can only provide a limited flow of hot water. This may create problems in larger households with more than one bathroom when multiple people try to shower at once. Turning on a hot water tap can also potentially lead to a colder shower for someone else.
Potential for simultaneous heating and hot water issues
Combi boilers typically cannot provide hot water and heating at the same time, with the former usually being given priority. This could lead to a colder home in some situations, such as if family members all take showers successively on a cold morning.
Potential for breakdowns
As combi boilers basically do more, there is a greater potential for breakdown, although this risk can be mitigated with an annual service.
Whatever you choose, Xgas can provide a boiler installation that’s right for you. Learn more about this and potential financing options.