The website promises a "gorgeous, roaring fire."
http://www.lennoxhearthproducts.com/products/fireplaces/crestline/ Perhaps they are being truthful?
Outside of the promised sound, the things that come to mind are: is the gas orifice the proper one for the gas source (LP vs natural gas)? Have the gas utility supplier and the installer confirmed proper gas pressure?
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Philip Kabza AIA
Partner and Dir Technical Services
SpecGuy
Charlotte NC
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