I got my Jotul GZ 550 DVII Acadia gas fire place installed in 2008 in a new construction. To make sure I do not have spider webs in the unit, I keep the pilot running year round. Fire place starts perfect, runs great however, over the past couple of years it seems that the flames are much lower than what they use to be when it was first installed. There is a flame level adjustment knob in the unit and even at the highest setting the flames are very low. Any suggestions / advice will be greatly appreciated.