Millivolt systems include a standing pilot light that ignites the burner. The pilot also heats a small thermopile, which generates a tiny electric current (measured in millivolts) - just enough to operate the controls on the gas valve when you switch it on or when a thermostat calls for heat. Because a Millivolt system does not require electricity, it allows the fireplace or heater to operate without interruption during power outages.
DVE heaters that exceed 80 percent efficiency and Mantis fireplaces that exceed 90 percent efficiency employ advanced electronics, hot-surface ignition, and power venting through multi-stage heat exchangers to achieve these lofty efficiencies.
Multi-Function Systems use a small electronically generated spark to ignite the burner. This eliminates the standing pilot, which saves about 800 BTU/Hour on a direct vent system.
Because they can operate with battery backup, multi-function systems can provide heat during a poweroutage.
Multi-function systems include their own remote controls. Available on some direct-vend fireplaces andvent-free burners (FQ-VFSV).
IP Systems use a small electronically generated spark to ignite a pilot, which ignites the burner. This eliminates the standing pilot, which saves about 800-1100 BTU/Hour.
Most IP systems include their own remote controls - either an on/off (for outdoor products) or thermostat (used mostly on direct-vent and vent-free fireplaces).