Boiler Types and Efficiency

If you are thinking of purchasing new boiler and would like to compare number of new boiler efficiencies we recommend using official SEDBUK boiler efficiency rates.  SEDBUK rates are also useful in comparing old to new boiler ratings. Whenever your old boiler (min 5 years old) starts breaking we highly advice exchanging for a new model, mostly because new boiler will be much more efficient, resulting in lower heating costs and we estimate that new boiler purchase will return in 1.5-2 years.

All Grant boilers are condensing  boilers. The main difference between traditional and condense solution is that condensed is designed to catch this part of heat  in combustion process that is normally lost in flue system channel (traditional boilers). Grant Vortex models are equipped with stainless steel heat exchangers that come together with special baffle system that extracts the heat. Thanks to this extra energy is constantly provided, boiler stays on high efficiency level which straightly results in lower heating costs (up to 20%) and  lower hot water costs (up to 25%). What’s more your new oil fired boiler can be combined with Solar Thermal Solutions or Air Source Heat Pumps installation providing even further savings on electricity.

Grant boilers are being installed and commissioned at the same time. This way whenever boiler specialist leaves your home you have the guarantee that your boiler is operating correctly. Installation and commissioning doesn’t take more than a half a day, standard annual check-up takes around 1 hour. Modernly designed, most models will fit into kitchen or utility room. Efficiency ratings on all models reach ‘A’ level. Biomass Grant boilers operate at the same manner as oil fired boilers giving more control over energy usage. Biomass boilers are most effective when wooden pellets or wooden chips are being used as a fuel (most efficient eco-fuel).

If you wonder what model to choose, our recommendation based on a size of your home/apartment would be:

  • smallest apartment- here choose VortexBlue Eco or Vortex Pro Kitchen with an output  of 15 kW
  • smallest houses where no gas/oil provider but free garden/garage space available choose renewable solution, biomass boiler Spira or Vectra condensing boilers with outputs starting at 4kW and go up to 36 kW
  • standard and big houses- go for the awarded models VortexBlue Internal or External with outputs 21kW, 26 kw and 36kW

Advantages of replacing your old boiler for Vortex or Spira/Vectra condensing boilers

  1. You choose if to go with renewable energy or modern oil fired boiler
  2. Almost all heating solutions provided by Grant Boilers can be combined with Solar Thermal Solutions or Air Source Heat Pumps technology proving further savings not only on gas but also electricity bills.
  3. High variety of outputs provides good choice for any size of house/apartment
  4. Nice design, no need for big space
  5. Boilers work with either  Grant EZ-Fit oil or wood pellets/chips for biomass boilers
  6. Manual diagnostics
  7. Relatively fast installation and service
  8. External models have external powder-coted casing provided


After checking efficiency rate of your existing boilers and comparing it with effiencies of new Grant boilers,  you would most likely want to install one of the Grant Vertex boilers. Company gained over 20 awards in last 10 years including Innovative Product of the Year 2016 and Best Renewable Products 2015 . If you feel you have enough of repairing your old boiler don’t hesitate ask for quotation and choose a new Grant boiler today!

Grant Boilers offer one of the nicest designs  fully combinable with further renewable solutions like solar panels or small wind turbine systems,they don’t take much of a space- except with Spira/Vectra condensing biomass boilers.   Most of Vertex models have built in frost protection.