3120 HEWITT AVE 2018-01-02 MF Import

May 18, 1976 the Evergreen CITY or everett Washington Natural Gas Company CITY HALL . 2]9-0 ]4] 815 Mercer Street EVERETT. W.1I GTON Post Office Box 1869 Pn3GI Seattle, Washingtcn 98201 INSPECTION DEPARTMENT Reference: Make Up Air heater at the Brokerage Restaurant 3120 Hewitt, Everett, Washington Attention: Mr. Jack 0. Wood Dear Mr. Wood: We have reviewed your letter dated May 6, 1976, and find we are in disagreement with the interpretation and intent of the Uniform Mechanical Code, relative to the installation of the direct -fired gas make-up air heaters as installed at the referenced building. Item No. 2: Sections 1904(e) and 1904(e)l, rc:7uire two separate safety controls. Section 1904(e) requires an electrical interlock between the coresponding exhaust system (not exhaust fan) and the direct gas -fired make-up air heater so that it (the make-up air heater) can be in operation only when the exhaust system is in operation. Note that this Section (1904(e) only references the exhaust system (not exhaust fan) and the make-up air heater. (Not the main gas valve.) In addition to the above requirement, Section 1904(e)l requires an additional safety control, i.e. "such equipmcnt" (the make-up air heater) "shall be pruvided with air -flow sensing devices so designed and installed as to shut off the gas burner upon failure of either combustion air or main air supply. (Controls actuated by failure of the power supply to the blower motor do not meet this requirement.)" The intent of the code is quite apparent in this application of direct gas -fired make-up air heaters. Due to the inherent characteristics of a direct -fired unit which is unvented and is dependent on electronic safety control devices to eliminate the possibility of the unit discharging products of combustion, improperly diluted into a confined habitable area where many open flame appliances are utilized and the protection of the area is dependent upon the exhaust system.