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GEM CS3 26/35 Oil - Boiler Efficiency Ratings

Boiler Efficiency Rating

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 0800 327 7119 for a no-obligation quote, alternatively visit Boiler Guide to request quotes from independent local and regional heating engineers.

GEM CS3 26/35 Efficiency

SAP seasonal efficiency93.0%
Rating bandBand A


ManufacturerGEM Boilers
ModelCS3 26/35
Fuel TypeOil
Flue TypeOpen or Room-Sealed
FanFan Assisted
Output (kW)26 - 35
Boiler ID
Manufactured From/To2007 - current


The GEM CS3 26/35 is an 'A' rated boiler which has an excellent efficiency of 93.0%.

The CS3 26/35 is a Condensing Conventional boiler with a maximum power output of 35kw that uses Oil 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 GEM Boilers to the CS3 26/35
(Condensing Oil Conventional)

Results ordered by efficiency. Some models may be obsolete.

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