Whether you are replacing an old boiler or fitting one in a new build, a condensing boiler is the right choice. It has been the European standard since 2015, uses significantly less gas than conventional models and cuts heating bills by a meaningful amount every year.
What is a condensing boiler?
A condensing boiler provides domestic hot water and central heating, but it does something conventional boilers do not: it recovers heat from the exhaust gases that would otherwise escape up the flue as water vapour. Traditional boilers burn gas and let that waste heat go. Condensing boilers capture it through a heat exchanger, which is how they achieve efficiencies above 100% (net calorific value).
How does a condensing boiler work?
Think of a pot of water boiling on the hob.
A conventional boiler is the pot without a lid: a significant share of the heat produced simply escapes.
A condensing boiler is the pot with a tight-fitting lid: it holds onto that heat and puts it back to work, using far less gas in the process.
The recovered heat does two useful things:
- Pre-heats the cold water feed, so hot water comes through almost immediately when you open the tap.
- Cools the flue gases to around 40°C, which substantially reduces emissions.
Condensing boilers and current regulations
Because of their higher efficiency and lower emissions, condensing boilers became the mandatory European standard on 26 September 2015.
EU Directive 2009/125/EC ended the manufacture of conventional open-chamber boilers and banned their installation in most cases. If you are replacing or installing a boiler today, you need a condensing model.
The savings are genuine. Compared with an older appliance, a condensing boiler can trim your heating bill by several hundred euros a year.
Browse our condensing boiler range.
Incentives and rebates
Installing a condensing boiler may qualify for European energy efficiency incentive programmes. The schemes available vary by country, so check what applies in your area before you buy.