Condenser Boiler Types

what is a condensing boiler?


Condenser Boilers TypesThis is not really a specific brand or product, the condensing aspect is really referring to the processes the boiler uses to increase its efficiency.

By minimising heat loss through a series of design features, they use the latent heat of water vapour produced from burning natural gas to increase efficiency.

In other words, a condenser boiler reduces the amount of fuel being used by “recycling” the waste produced during the heating process.

With a regular non-condenser the fuel (normally natural gas), when burned, gets passed through a heat exchanger in which the heat is transferred to the water supply thereby increasing its temperature. During this process water vapour is produced and non-condensing designs eject this water vapour and waste the potential.

This is the reverse for a modern condensing model where these gasses are allowed to rise through a primary heat exchanger to a secondary unit which extracts more heat from the water vapour. This helps to increase the efficiency of the device from around 70% for an older boiler up to around 90 or 95% for new models.

Energy Efficient Condensing Boiler


This “recycling” of waste is what allows the designs to get “A” ratings for energy efficiency. What that means is, you get more heat for less fuel which translates into saving money on your monthly gas bill.

A condenser design can be a System boiler, Open Vent boiler or even a Combi and is currently the type of design that will be fitted to all new & replacement systems. It is now an obligatory requirement in the UK for this design to be used.

Some people mistakenly think that Combi or combination means condensing, but this is not the case as you can get both condensing & non-condensing combi products.

Additional Beneficial Features


You can take advantage of design features that optimise the work load, such as modulation. This means that rather than turn on & off to manage temperatures, they simply slow down & “tick over” to keep the right temperature – this is a lot less work for the boiler.

Optimising thermostats when combined with modulation brings more sophistication to the system. This allows monitoring of outside temperatures to see if it is higher or lower than the day before. With this information it will work out how long it will take to warm up the house and make adjustments beforehand – in effect your boiler kind of “learns” as it goes along which is really clever.

All new & replacement boilers must be fitted by a “Gas Safe” registered company or engineers, do not consider any offer that comes from an unregistered installer – find out more about certification here: Gas Boiler Installer Certification

If you are not sure about which product suits you best you can take look at different Boiler Types

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Points to note before replacing or buying a new Condenser Boiler


In any event, to make sure you get the right system you should rally take the time to get an engineer around to your home to establish your hot water & home heating requirements. This is advisable as there are several factors that can impact on which system will work best in your home.

For example, is your home in a hard or soft water area? If you get hard water you may benefit from using a stainless steel heat exchanger which is easier to clean lime-scale deposits.

An experienced installation engineer will take into account the amount of radiators, windows (are they double glazed?) home insulation, high ceilings, low ceilings, room sizes, bathrooms, taps & general hot water demand peaks. They can all factor into how to choose & configure the optimal boiler for your needs.

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