A ventless fireplace powered by propane gas can be installed in almost any room where you need heat. If the room is already equipped with a gas line to the house propane tank, use that line to connect the heater. Otherwise, you'll need to hook up the heater with the supplied regulator to a smaller propane tank, such as the cylinders commonly used with gas grills. Both connection types use standard couplers for attaching to the gas line.
Place the heater in the room away from curtains and furniture.
Screw on the propane gas line in your room, if it is equipped with a propane line, to the port on the back of the heater. If using a portable tank, connect the small coupler on one end of the regulator hose that comes with your heater to the port on the back of the unit. Tighten by hand, then finish the connection with a 1/2-turn using pliers.
Attach the other end of the regulator hose to the propane tank and tighten by hand only. If using an installed line in the house, the line should already be connected to your outdoor tank.
Add liquid soap to a bucket of water and swirl to form suds. Soak a disposable cloth in the bucket.
Turn on the gas to the heater by unscrewing the knob on the top of your tank.
Remove the disposable cloth from the bucket and twist the cloth over the gas connection at the tank and the heater. Watch the soapy water for signs of sputtering or bubbling, which mean there is a gas leak. If there is any sign of leaking, close the tank and repeat the hookup at each end.
Some ventless heaters may raise the air moisture in a room, so you may need to set up a dehumidifier as well, if the room develops a damp, humid feeling in the air while the ventless heater is operating.