Lowe's and Direct Brand have a select number of parts, such as thermocouples and igniters. Some parts dealers are experiencing a shortage of parts available for these units, as of 2015, according to ProcomHeaters.net.
ProCom heaters are vent-free units that use natural gas or propane as a fuel. The heaters are either freestanding or wall-mounted. They are available in blue flame, yellow flame or catalytic ceramic models, as of 2015. Installing one of these units eliminates the hassles of heating with wood and is sometimes a good option for homes that use electric heat.
Elimination of the vent allows the homeowner to install the heater in a central location, away from an outside wall for more even heat distribution. The heaters are over 99 percent efficient and economical to operate. Installing one of the units in a home allows the occupants to turn the thermostat for the central heating system down and enjoy the benefits of zone heating.
Vent-free gas heater manufacturers have improved the safety of these units by adding oxygen sensors that automatically extinguish the flames if they detect a lack of oxygen in the room. However, as of 2015, California does not allow the use of unvented heating systems.