Napoleon Direct vent fireplaces have enabled far greater flexibility in the placement of home heating units because they don't need access to a masonry chimney or a freestanding flue above the roofline. Prefabricated from metal, they use zero-clearance technology and have a glass door that securely seals the combustion area from interior rooms. Air for combustion is drawn from the outside. Air for convection is drawn from inside the room, circulated through passageways around the firebox
and heat exchanger, and then returned it to the living
Napoleon Direct vent fireplaces burn very efficiently, extracting most of the heat from the combustion gases. Unlike wood-burning stoves, they produce virtually no particulates, require little user maintenance or clean-up, and are simple to operate, using a switch, or even a remote control, and a thermostat.
One-sided models are the norm, but two-sided, three-sided (napoleon peninsula fireplace), and four-sided (napoleon island fireplace), bay-window shaped (napoleon bay fireplace, and corner units (napoleon corner fireplace), are also available. Sizes vary from about 30 to 48 inches (76 to 122 cm) wide, about 24 to 30 inches (51 to 76 cm) high, and about 13 to 18 inches (33 to 46 cm) deep.
Nearly all manufacturers make both top and rear venting models. Top-venting types work well where there isn't a straightforward access out of a wall. Depending upon the model, vents may run vertically or horizontally for quite a distance - up to 25 feet (7.6 meters) or more.
Blower fans are available as options on almost all Napoleon and Majestic fireplaces.
Some Napoleon models have a standing safety pilot light that burns continuously to light the main burner whenever the gas is turned on. Others have electric spark ignition, to save energy, or a piezo electric ignition, which doesn't require an electrical hookup. Some units use a millivolt generator so the fireplace can operate even if mains power fails.