Furnace #1 - precision tune up; clean and tune up furnace; clean burners, test ignition components, adjust gas level, test safety circuit, check indoor motors, checked all electrical components, tested indoor air flow, checked heating temperatures, and tested overall furnace operation. Replaced 4†media filter. Recommended Surge protector to prevent power surge and damage the electrical components. Recommendations has been declined as of now. Furnace #2 - precision tune up; clean and tune up furnace; clean burners, test ignition components, adjust gas level, test safety circuit, check indoor motors, checked all electrical components, tested indoor air flow, checked heating temperatures, and tested overall furnace operation. Replaced 4†media filter. Recommended Surge protector to prevent power surge and damage the electrical components. Recommendations has been declined as of now. Furnace #3 - precision tune up; clean and tune up furnace; clean burners, test ignition components,