Guide Specs
Series SMC, Steam Make-Up Air Heater, Centrifugal Type, SK-880-85, Nov 1997
Series SMC was formerly known as Series 85; the below guide spec will be updated shortly to reflect the change.
The Steam Make-Up Air Heater, Centrifugal Fan, shall be manufactured by Hartzell Fan, Inc. and identified as Series 85. The design shall be classified as a draw-through type, indoor or outdoor, packaged configuration, for vertical or horizontal installation. Units shall be a modular assembly consisting of a fan section, optional filter section, and a heating section. The fan section will contain one or more electric motor powered, belt driven, centrifugal fans. The filter section will contain a framework supporting reusable or throwaway type air filters. The heating section shall consist of a steam-to-air heat exchanger; a control system to activate/deactivate the unit, modulate the outlet air temperature and protect the integrity of the coil, and an access door for service purposes. Fifteen models shall be available providing 741,000 to 3,825,900 Btuh heating capacities (using saturated steam at 5 psig and an entering air temperature of 0° F.).
The centrifugal fan(s) shall be double width, double inlet (DWDI) wheel design with forward curved blades formed of low carbon steel. The fan wheels shall be mechanically attached to and supported by tubular steel shaft. Pillow block ball bearings having extended grease lines shall support the fan shaft laterally in the unit. The unit shall be belt driven. The motor will be of the open-end, protected type. Belt guards will be furnished as standard.
The steam-to-air heat exchanger shall be a non-freeze type coil design incorporating tube within a tube construction. Coil headers shall be constructed of steel with threaded pipe nipples for inlet and outlet connections. The coil casings will be formed of 16 GA galvanized steel. Coils shall be mounted on rails within the housing to facilitate removal.
The housing will be formed from 12 gauge welded, hot rolled, low carbon steel sheet. Construction shall be modular incorporating bolted and gasketed reinforced flanges at joints interconnecting sections of the housing. The housing shall be protected from corrosion by an application of an industrial air-dry enamel paint. Each housing shall be provided with a motor operated, center pivoted, inlet shutter, and an access door.
A control system with a NEMA 4/12 cabinet shall be furnished. A modulating steam control incorporating a steam valve with an actuating motor, a discharge air temperature sensor, and an outdoor air temperature compensating controller shall regulate the flow of steam to the coil. A low temperature safety shutdown thermostat shall be incorporated. Other controls include an end switch integral to the damper motor; a control transformer; a magnetic, full voltage, fan motor starter; fuses and fuse blocks; and a terminal strip. A remote operating station with indicating lights shall also be included with the unit.
ACCESSORIES:
Heavy Duty Coil - Longer life, Cupro-Nickel coils available for 75 psig and above steam pressures.
Room Thermostat - Automatic, remote room temperature control.
Service Platform - Raised flooring for maintenance and service.
Turning Elbow - Duct for 90° redirection of airflow.
Filter Box w/Filters - Housing supporting reusable or throwaway type filter elements.
Recirculated Bypass Section - Louvered ductwork allowing reheating of room air.
Two and Four Way Outlet Diffusers - Adjustable louvers providing directional control of discharge airflow.
JIC Disconnect Switch - Safety device which de-energizes unit without opening control cabinet.
Inlet Weatherhood - Downward turned elbow which minimizes entrainment of snow and rain.
Combination Motor Cover/Belt Cover - Enclosure providing weather protection for motor and operator safety around moving equipment.
Special Motors - Special constructions and manufacturers models are available.
