The Advent 13,500 BTU roof-top air conditioner with heat pump was designed specifically for the rigors of the RV lifestyle. Backed up with a No-Hassle, 2-year Warranty, the system is easy to install and operate, fitting into a standard 14 1/4" x 14 1/4" vent opening for easy replacement of your existing unit. Features include an extremely rigid frame consisting of a composite of foam and metal parts allowing for quieter operation; Premium, extra-thick water seal gasket keeping moisture from leaking into the RV; Removable and washable filters that keep the interior clean and free of debris; Motor overload protection for longer life; Non-ozone depleting environmentally-friendly refrigerant. A ducted ceiling package featuring a digital thermostat is sold separately (77-9113). The digital thermostat allows you to set the desired temperature in 3 mode settings: Fan, Cool, Heat. Roof unit dimensions are 37.4" L x 30.3" W x 15.4" H.