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Worcester Heatslave 20/25RS 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.

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Worcester Heatslave 20/25RS Efficiency

SAP seasonal efficiency70%
Rating bandUnknown


ManufacturerWorcester Boilers
ModelHeatslave 20/25RS
Fuel TypeOil
Flue TypeRoom-Sealed
FanFan Assisted
Output (kW)20 - 25
Manufactured From/ToUnknown - 1996


The Worcester Heatslave 20/25RS is unrated, this probably means it's obsolete or very old.

The Heatslave 20/25RS is a Non-Condensing Combi boiler with a maximum power output of 25kw that uses Oil as its fuel source.

Being an Unrated boiler it would be worthwhile replacing it with a higher efficiency 'A' rated boiler.

Similar Worcester Boilers to the Heatslave 20/25RS
(Non-Condensing Oil Combi)

Results ordered by efficiency. Some models may be obsolete.

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