THERMOTANK Condensing Gas Boiler Condensing Gas Boiler Natural gas and LPG compatible premix burner PWM Controlled burning stainless tank 104% efficiency with condensation technology Adjustable water temperature Economy mode option frost protection Inefficient combustion audible warning system Heat exchanger lime bonding audible warning system Anti bacterial protection 21 time schedules weekly and daily cathodic protection Waterless working safety Over temperature safety system Vinleks faux leather outer cover External touch LCD display Quiet operation