Specifications include, but are not limited to: A.The equipment covered by these specifications shall be of standard design, and of proven ability as manufacturedby reputable concerns having long experience in the production of such equipment. The equipment furnished shallbe designed and constructed in accordance with best practice methods.B.Make up Air (MAU) shall be sized for 4,535 CFM at 0.25” w.c. external static or equivalent. ETL certified to theANSI Z83.4b-2006/CSA 3.7B-2006.C.MAU shall be designed for natural gas fuel. Gas connection shall be roughed to the outside of cabinet.D.Direct gas fired 343 MBH Aluminum Cast Burner with 30:1 turndown capability and low emissions style stainless steel baffles or equivalent.E..75” FM/ETL interrupted pilot ignition manifold with UVF.MAU shall be of horizontal configuration with the discharge direction for the unit (as installed) shall be down.