Condenser Coil Guard — Metal grille with PVC coating shall be provided to alleviate coil damage.
Black Epoxy Coated Condenser Coil — This factory installed option is designed to provide corrosion protection of air cooled condenser coils for seacoast application. The black epoxy coil protection is a factory applied thermoset vinyl coating, bonded to normal aluminum fin stock. The uniform thickness of the bonded vinyl layer exhibits excellent corrosion protection in salt spray tests performed in accordance with ASTM B177.
Air Handlers
General
Air handler units shall be completely factory assembled including coil, condensate drain pan, fan motor(s), filters, and controls in an insulated casing that can be applied in either vertical or horizontal configuration. Unit shall be rated and tested in accordance with ARI standard 340/360. Unit shall be UL listed and labeled in accordance with UL 1995 for indoor blower coil units.
Casing
Unit casing shall be constructed of zinc coated, heavy gauge, galvanized steel. Exterior surfaces shall be cleaned, phosphatized, and finished with a weather-resistant baked enamel finish. Casing shall be completely insulated with cleanable, foil faced, fire-retardant, permanent, odorless, glass fiber material. All insulation edges shall be either captured or sealed. Knockouts shall be provided for unit electrical power and refrigerant piping connections. Captive screws shall be standard on all access panels.
Refrigeration System TheTWE050A,TWE075A,TWE100A units shall have a single refrigeration circuit and theTWE100B,TWE155B,TWE200B units shall have dual refrigeration circuits. Each refrigeration circuit is controlled by a factory installed thermal expansion valve.
Evaporator Coil
Configured aluminum fin surface shall be mechanically bonded to 3/8" (10 mm) internally enhanced copper tubing and
shall be factory pressure and leak tested at 375 psig (2586 kPa). Coil is arranged for draw-through airflow and shall provide a double sloped condensate drain pan constructed of PVC plastic.The drain pan shall be removable for cleaning.The condensate drain pan can be installed in any of four positions allowing for vertical or horizontal application and providing external connections on either side of the unit.
Evaporator Fan
Double inlet, double width, forward curved, centrifugal-type fan(s) with adjustable belt drive shall be standard. Thermal overload protection shall be standard on motor. Fan and motor bearings shall be permanently lubricated. Oversized motors shall be available as an option for high static application. All indoor fan motors meet the U.S. Energy Policy Act of 1992 (EPACT).
Controls
Magnetic evaporator fan contactor, low voltage terminal strip, check valve(s), and single point power entry shall be included. All necessary controls shall be factory-installed and wired. Evaporator defrost control shall be included to prevent compressor slugging by temporarily interrupting compressor operation when low evaporator coil temperatures are encountered.
Filters
One inch, throw-away filters shall be standard onTWE050A,TWE075A, TWE100A andTWE120B model air handlers. Filters shall be accessible from the side coil access panel. Filter rack can be field converted to two inch capability. Two inch, throw-away filters shall be standard onTWE155B andTWE200B models.
ACCESSORIES
Electric Heaters — UL and CSA approved electric heat modules shall be available for installation directly on fan discharge. Electric heaters shall be available in a wide range of capacities with one or two stage control, single- point electric power connection, and terminal strip connections. Electric heater elements shall be constructed of heavy-duty nickel chromium elements internally wye connected on 400 volt,
three phase. Each 400 volt heater shall have automatic line break high limit controls.
Discharge Plenums and Grilles — Accessory discharge plenums shall be available for vertical, free discharge applications. Plenums shall be constructed of heavy-gauge, zinc coated, galvanized steel finished with baked enamel to match the air handler unit. Grilles shall be satin finished aluminum and have four-way adjustable louvers.
Return Air Grilles — Accessory return air grille shall be provided for vertical front, free return applications. Grilles shall be installed in place of the front lower side panel. Grille shall be satin finished aluminum with non-adjustable louvers.
Mounting Subbase —The accessory shall be available for vertical floor mount configurations. Subbase shall be constructed of heavy gauge, zinc coated, galvanized steel with baked enamel finish to match air handler unit. Subbase is required in the vertical air flow application for condensate drain trapping and when isolators are required.
Vibration Isolators —This accessory shall reduce transmission of noise and vibration to building structures, equipment, and adjacent spaces. Packages shall be available in either neoprene-in shear or spring-flex types in floor or suspended mountings.
Oversized Motors — Field installed oversized motors shall be available for high static pressure applications.
CONTROL OPTIONS
Standard IndoorThermostats —Two stage heating and cooling operation or one stage heating and cooling thermostats shall be available in either manual or automatic changeover.
Programmable Electronic Night Setback Thermostat —The option shall provide heating setback and cooling setup with 7- day programming capability.
OutdoorThermostat —This option shall provide staging control of electric heaters based on a set outdoor temperature.
