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Worcester Bosch/British Gas CS1 ZB 7-28A Gas - 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.

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Worcester Bosch/British Gas CS1 ZB 7-28A Efficiency

SAP seasonal efficiency90.7%
Rating bandBand A


ManufacturerWorcester Boilers
ModelBosch/British Gas CS1 ZB 7-28A
Fuel TypeGas
Flue TypeRoom-Sealed
FanFan Assisted
Output (kW)27.4 - 27.4
Boiler ID
Manufactured From/To2001 - 2003


The Worcester Bosch/British Gas CS1 ZB 7-28A is an 'A' rated boiler which has an excellent efficiency of 90.7%.

The Bosch/British Gas CS1 ZB 7-28A is a Condensing Conventional boiler with a maximum power output of 27.4kw 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.

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