I have a Drolet Escape 1800 fireplace insert. How much clearance from the top of the inserts heatshield to the bottom of the metal faceplate should there be? The blower motor kicks on at the proper temperature but there isn't any airflow coming from the top of the insert. The representative at Drolet stated that the blower motor sucks in the rooms air and blows it out the top of the insert. they recommended 1" from the top of the insert (heatshield) to the bottom of the metal faceplate. Can someone concur if this is true? The installation manual doesn't mention this at all. Thank you.