The most energy-efficient boiler on the market is a condensing boiler. Their high efficiency is achieved by removing heat from the fuel they burn and cooling the combustion products so much that the water vapour inside them turns to liquid as they are cooled. Approximately 55°C is the temperature at which this occurs. Boilers that cool flue products this much need larger, more efficient heat exchangers than traditional boilers.
So why aren’t all manufactured boilers condensing?
First of all, in order to remove the liquid water, the condensate, from the boiler safely, it is necessary to use materials not normally used in conventional boilers.
When the temperature is this low, the flues products lose their natural buoyancy, so a fan is needed to remove them.
In addition, larger heat exchangers are more expensive, so condensing boilers will cost more and it takes very clever design work to ensure the user can save more in reduced fuel bills than they pay for the extra cost.
Malvern Boilers uses a design that accomplishes this. Using a copper heat exchanger for the first part, and an aluminium heat exchanger for the second part, we have split the heat exchanger into two parts. On the water side of the system, aluminum is not as good as copper on the condensing side. Our second heat exchanger is lined with copper as a result. The Malvern Condensing Boiler therefore sees only copper.
In addition to releasing energy as it becomes liquid, water vapour also releases latent heat as it turns into a liquid. As a result, a condensing boiler is likely to have a 15% greater efficiency than a modern non-condensing boiler. Fuel efficiency, carbon dioxide production, and operating costs are all impacted by how efficient a boiler is.
An article will be written about comparative efficiencies and running costs.
Frequently Asked Questions
Are Condensing Boilers Expensive?
Due to the reasons already mentioned, they are more expensive, but they should pay for themselves within two years.
Aren’t they more complex and difficult to service?
It is no more complicated than a modern powered flue boiler to build a Malvern condensing boiler using industry standard components.
Are there special installation requirements?
The condensate must be drained away by a pipe during installation. Alternatively, it can be discharged into a mini soakaway that is connected to any of the property’s existing waste water outlets.
Do you need large radiators?
There is no need to change the radiator sizes, they will be fine. In a future article, this will also be discussed in greater detail.
Do you need complicated system controls?
Room thermostats, electric valves, and cylinder thermostats are the minimum standards for any domestic installation. The same applies to condensing boilers. Thermostatic Radiator Thermostats (TRV’s) can also be installed, but a bypass must be installed if they are installed on every radiator.