Thermal transfer and direct fire systems are the heating system of the gas supported roasting machines. Thermal transfer or indirect-fired roasters are designed with a burner(s) which creates burner flame does not touch the coffee beans. However, the gas heating from the burner is for actualizing the coffee, malt or cacao roasting. Direct-fired roasters has the opposite activity compared with thermal transfer since it contacts the beans through drum with the burner flame.