The FURNACE has three burners and the FORCE has two burners so the technique is slightly different but the convection science is still the same. The idea of convection heating is to cook ‘slow and low’.  When the hood is down, we recommend having only one burner on low or medium setting (depending on the weather). Place the meat over the section with the burners completely off; this will generate a great 360 degrees hot airflow around the meat without scorching the underside (the indirect method).
Remember to NEVER leave the burners on high with the hood down for more than 5 minutes – the BBQ will overheat. For even better results, try the Everdure by Heston Blumenthal roasting rack .