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 4.8 stars

1,932 reviews

 4.8 stars

1,932 reviews

Worcester Bosch Greenstar Heatslave II 18/25 Combi Oil Boiler

Worcester Bosch Greenstar Heatslave II 18/25 Combi Oil Boiler Boiler
Typical Price (inc VAT)
£2,395
Typical installation Cost (inc VAT)*
£1000 - £1500
Sundries (Filter, Flue, etc)
£300
Total Cost
£3,695 - £4,195
Make Worcester Bosch
Model Greenstar Heatslave II 18/25 Combi Oil Boiler
Is Condensing Condensing
Efficiency Rating 90%
Band Rating A Rated
LPG Compatible No
Standard Warranty Up to 5 Years
Central Heating Max. Output 25 kW
Mounting Floor Standing
Flow Rate 18 l/m
Typical Price (inc VAT) £2,395
Typical installation Cost (inc VAT)* £1000 - £1500
Sundries (Filter, Flue, etc) £300
Total Cost £3,695 - £4,195
ERP Rating A Heat B water
Hot Water Max. Output 25 kW

* This is a guide price for a straightforward, like-for-like boiler replacement. Installation costs will vary dependent on work required.

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4.7/5 out of 26,479 reviews

1,8 million quotes provided in 10 years

Product Description Greenstar Heatslave II 18/25 Combi Oil Boiler

Worcester Bosch Greenstar Heatslave II 18/25 is a compact combi oil boiler that has an output rating of 25 kW.

How efficient is the Greenstar Heatslave II 18/25?

This is a highly efficient combi with an efficiency rating of 90% and ErP A-rating for heating that could potentially save you money on your energy bills.

Is the output rating suitable for my home?

The output rating of 25 kW is perfectly suited to medium-sized homes with a single bathroom and around 15 radiators.

What options are available?

This 25 kW model sits in the middle of the 3 available in the Greenstar Heatslave II range, with a lower 18 kW output and higher 32 kW output. Additionally, Greenstar Heatslave II boilers are also available as system and regular units for external as well as internal installation.

Is a combi boiler suitable for my home?

A combi boiler is suited to properties with 1-2 bathrooms. Should you have a higher demand for hot water then a heating system that stores hot water in a cylinder, such as a system or regular boiler, would be the better option.

How long is the warranty?

Greenstar Heatslave II boilers feature a 2 year warranty as standard which the option to extend this to 5 years under certain terms and conditions.

What are the key features of the Heatslave II combi boiler?

Some of the key features of the Greenstar Heatslave II include sleek design, hot water flow rate of 18 litres per minute. a concealed drawer to hide the heating controls in, eco hot water mode to increase efficiency and compact dimensions for space-saving installation.

How big is the Greenstar Heatslave II combi?

Greenstar Heatslave II combi boilers are compact in size, with dimensions of 855 x 520 x 600mm (HxWxD), so they can be installed under a standard kitchen worktop.

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Quickly compare 3 FREE quotes

  • Quotes from local engineers
  • Get quotes today, installed tomorrow
  • Finance options available
  • Save up to £500 on installation
Get Quotes Now It only takes 30 seconds
0330 808 0405
Call us to get quotes

We will get you the best deal!

0330 808 0405
4.7/5 out of 26,479 reviews

1,8 million quotes provided in 10 years

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