Natural gas or LPG passes through the gas valve assembly inside the unit, where it is mixed with combustion air and ignited individually within the tube heat exchangers using an electronic ignition module. The hot combustion gases are circulated inside the heat exchangers by a fan and expelled as exhaust once cooled. As the tube heat exchangers heat up, the rear fan of the unit activates, drawing in cold air from the environment and passing it through the heat exchangers to be released as warm air. This cycle continues with increasing efficiency as the space warms up. Once the desired temperature is reached, the control panel or thermostat stops the system, restarting it when the temperature drops.
