Boiler Efficiency Ratings

Compare new boilers and assess whether your current boiler would be better off being replaced

Our boiler efficiency tables provided by SEDBUK (the seasonal efficiency of domestic boilers in the UK) provide a guide of how effective your boiler is at turning fuel into heat.

You can check your boilers rating by selecting it’s make and model below. Ratings are based on the SEDBUK Rating which is an indicator of its efficiency when used within an average domestic household, it’s a great benchmark for comparing new boilers and also assessing whether your current boiler would be better off being replaced due to low efficiencies.

For new boiler installations call British Gas Boilers on 0333 230 5216 for a no-obligation quote, alternatively visit Boiler Guide to request quotes from independent local and regional heating engineers.



RKA 29 Efficiency

SAP seasonal efficiency


Rating band

Band A


ManufacturerRadiant Boilers
ModelRKA 29
Fuel TypeGas
Flue TypeRoom-Sealed
FanFan Assisted
Output (kW)29.43 - 29.43
Boiler ID
Manufactured From/To2007 - current


The Radiant RKA 29 is an 'A' rated boiler which has an excellent efficiency of 90.8%.

The RKA 29 is a Condensing Combi boiler with a maximum power output of 29.43kw that uses Gas as its fuel source.

As this boiler is 'A' rated it will provide efficient heating and subsequently reduce fuel bills and carbon dioxide emissions.


Similar Radiant Boilers to the RKA 29
(Condensing Gas Combi)

Results ordered by efficiency. Some models may be obsolete.

Radiant RKA 18/100

91.4% Efficient

Radiant RKA 34/100

91.4% Efficient

Radiant RKA 29/100

91.3% Efficient

Radiant RKA 100

91.1% Efficient

Most Efficient Combi Gas Boilers

Alpha CD50

91.2% Efficient