Unit operates with natural gas. Included is a conversion kit that changes the unit from natural gas (NG) to liquid propane (LP) gas. Spark ignition features self-diagnostic control module. Includes 2 angle brackets for ceiling mount. Low Profile Design - can be installed in low-ceiling buildings. Minimum 8' clearance from floor to base of heater required. 1/2" gas connection. CSA certified. Power exhaust allows for Category 1 vertical or Category 3 horizontal venting (vent kit sold separately). Refer to model No. F102840 (SKU 445735) for 3" vertical vent kit or F102860 (SKU 445726) for 4" horizontal vent kit.