Opening the door to new opportunities

This year EOGB will launch Sapphire, the industry’s first fully modulating domestic oil burner which runs on kerosene. The new burner satisfies stringent EU regulations on NOx emissions which come into force in 2018 and will deliver the best in energy efficiency and carbon emission reduction of any domestic oil burner on the market today.

A standout feature of the Sapphire burner is the fact that it is fully integrated with OpenTherm technology, which increases efficiency even further and helps to significantly reduce fuel bills.

What is OpenTherm?

OpenTherm is the name given to a form of communication of information between modulating (condensing) central heating appliances and room thermostats, previously only available for gas boiler installations.

The term ‘open’ in the title means that boiler and controller manufacturers can easily bring their products together and work in partnership – something that has not been so easy in the past.

How does it work?

Many old boilers that don’t support OpenTherm have a simple on/off control system with mechanical room thermostat and time clock which means that the boiler is switched on and off at intervals to either provide full heat power or no heat at all.

On the other hand, with modulating control the heating power is increased or reduced based on the actual output needed. This means that means that we can be much more precise with temperatures by removing the on/off cycling and over shooting. Newer boilers which are OpenTherm-compatible allow thermostats to tell them when to adjust their heating water temperature and how high to set it. This means that the boiler will use only the amount of gas or fuel needed to reach the water temperature set by the thermostat.

You can tell if a product is OpenTherm compatible by looking for the following logo:





What are the benefits?

Some of the benefits of using OpenTherm include:

  • Higher efficiency – the controller will stop more fuel being burned than is actually needed
  • Carbon reduction – increased efficiency results in less emissions being produced
  • Longer boiler life expectancy – less stress is put on the boiler which in turn reduces any damage
  • Easy installation – there are just two cables involved

For more information on the OpenTherm-compatible Sapphire burner, contact our technical team on 01480 477066 or email

OpenTherm infographic