Locatated in Atascadero, The Sidel SRU flue gas condenser is designed to recover almost all of the waste energy that goes up the chimneys of natural gas or propane-fired boilers and appliances. Our goal is to increase the appliances efficiency by 10 to 15%. This recovered energy can be utilized for building heating, heating domestic water, process water or even swimming pool water._x000D_ We are here to help you save a lot of energy.