Comfort Glow DVP17 Direct Vent Liquid Propane Gas Wall Heater The Comfort Glow Direct Vent Gas Heater is a powerful and efficient vented propane heater that delivers 17,000 BTUs to heat spaces up to 570 sq. ft. This direct vent propane wall heater uses liquid propane and features a fully enclosed combustion system... $416.00 Add to Cart Add to Wish list Compare