Vortex Blue: Internal

10 Year guarantee*

Vortex Blue: Internal

The VortexBlue Internal oil-fired boiler has been designed to suit kitchen and utility room environments, combining Grant’s proven boiler technology with a revolutionary blue flame burner.

This range features a sleek white casing and neon diagnostic indicators within the control panel. With its state of the art blue flame burner, the VortexBlue Internal boilers deliver reliable, efficient operation with ultra-low NOx emissions.

a Heating

Features & benefits

  • *10 year guarantee when installed by a G1 Installer (Terms and Conditions apply)
  • Exceptionally efficient
  • Using the Riello blue flame burner, this results in a much cleaner combustion process producing very low NOx emissions
  • Neon diagnostic indicators make diagnostics easier
  • Designed to be installer friendly and simple to maintain
  • Compatible with Grant EZ-Fit flue systems
  • Heating engineers should visit the Professionals VortexBlue Internal range webpage to read more about these models
An introduction to blue flame technology

An introduction to blue flame technology

As the name suggests, the flame produced in a blue flame burner is blue in colour, rather than the usual yellow colour of standard burners fitted in Grant Vortex boilers. This blue flame results in a much cleaner combustion process, producing extremely low NOx emissions while also operating at very high efficiency levels.

Since September 2018, oil boilers installed in the UK have had to meet lower NOx emission targets and these targets may become more stringent in the coming years. With the VortexBlue range, Grant has taken the decision to future proof oil fired boilers by moving to very low NOx, blue flame technology well in advance of legislation.


Product code
Set Output
Max Output
NOx Emissions
Energy Rating
Load Profile
Energy Label
Product Fiche
VTXBF21 Grant VortexBlue Internal 21 (15-21kW) 21kW 21kW 130kg 860mm 470mm 603mm 90.81 Class 3 a Heating - View View


Home Heating Blog

Discover more about home heating solutions, care and support with our informative blogs

Read more

Find an Installer

Search our network of heating engineers to find local installation and servicing companies in your area


Looking for further product information?

Get the latest Grant brochures, data sheets and manuals from our comprehensive download centre.

Take me there


Use our online enquiry form to send us any comments or questions

Contact Us


There is a lot of terminology in the world of heating so this section is here to provide you with the definitions and clarity.

Learn more


Related products

Compare products