This HeatStar High-Output Indirect Forced Air Heater provides high-output air flow for large job sites, greenhouses, warehouses, tents and more. Can be used indoors or outdoors with appropriate venting (not included). Powerful fans pull massive amounts of cold air across a 4 loop heat exchanger, delivering clean and reliable indirect heat where you need it. Large 11.9-gallon fuel tank provides hours of uninterrupted operation. Heat exchanger keeps exhaust gas and heated air separate. Two-stage pump for more reliable starts in sub-zero temperatures. Long-life stainless steel combustion chamber and electronic flame control. Water-resistant flame control box. Automatic safety and control devices. Durable powder-coated finish. 110 Volts. Heats up to 7500 sq. ft.; capacity assumes temp rise of 20 to 60°F and 8ft. ceiling. Unit is equipped with heavy-duty 10in. pneumatic wheels and internal onboard diagnostics with a connection for an external remote thermostat.