I need some help on ventless fireplaces. Are ventless fireplaces only electric or can they also be gas. I was under the impression they could be gas also. Inspection today I had a gas log set in a manufactured fireplace with no exhaust flue/chimney. It had a gas cut off at the wall and a control knob and igniter under the gas logs themselves. First time to see this setup. I am wondering how this unit is vented. Any comments would be appreciated.