FIXED OUTDOOR AIR INTAKE DAMPER
This damper is shipped inside the return air compartment. It is completely assembled and ready for installation. A damper baffle inside the hood is adjustable to provide variable amounts of outdoor air intake on units that are not provided with an economizer or a motorized damper option.
Gasketing and mounting screws are provided in a parts bag attached to the hood assembly. Apply gasketing to the three flange surfaces on the hood prior to installing the hood. Extend gasketing 1/4" beyond the top and bottom of the two side flanges to insure adequate sealing.
Adjusting the damper to the desired air flow may be done before mounting the hood into position or (after installation) by removing the front hood panel or the screen on the bottom of the hood. Damper baffle in position 1 will allow approximately 10% recirculated air flow, position 2 approximately 15% and, to allow approximately 25%, remove the damper baffle.
On units with bottom return air applications, install the damper assembly over the opening in the side return air access panel. Remove and discard the opening cover and the covering over the hood mounting holes (used for shipping) before installing. Secure with the screws provided.
On units with side return air applications, install the damper assembly on the return air ductwork as close to the unit as possible. Cut an opening 16" high by 18" wide in the ductwork to accommodate the damper. Using the holes in the hood flanges as a template, drill 9/64" dia. (#26 drill) holes into the ductwork and secure with the screws provided.
CAUTION: If outdoor air intake will not be required on units with bottom return air applications, the damper assembly should still be mounted on the side return air access panel, per the instructions above, to insure moisture is not drawn into the unit during operation. The covering over the mounting holes only need be removed. Do not remove the opening cover.
FIG. 3 - FIXED OUTDOOR AIR DAMPER
CONDENSATE DRAIN
Plumbing must conform to local codes. Use a sealing compound on male pipe threads. Install a condensate drain line from the 1" NPT female connection on the unit to an open drain.
An alternate drain connection (1" NPT female coupling) is provided inboard on the same centerline as the exterior location.
NOTE: The condensate drain operates in a negative pressure in the cabinet. The condensate drain line MUST be trapped to provide proper drainage.
FIG. 4 - RECOMMENDED DRAIN PIPING
COMPRESSORS
Units are shipped with compressor mountings
CAUTION: Do Not loosen compressor mounting bolts.
FILTERS
2" filters are supplied with each unit. Filters must always be installed ahead of the indoor coil and must be kept clean or replaced with same size and type. Dirty filters will reduce the capacity of the unit and will result in frosted coils or safety shutdown. Minimum filter area and required sizes are shown in the Physical Data table.
SERVICE ACCESS
Access to all serviceable components is provided by the following removable panels:
•Compressor compartment
•Electric Heat compartment
•Side Supply & Return Air compartments (Two panels)
•Blower compartment (Three panels)
•Main control box
•Filter compartment
•Outdoor Air compartment (Two panels)
Refer to Dimensions and Clearnaces Figure for location of these access panels.
CAUTION: Make sure that all screws and panel latches are replaced and properly positioned on the unit to maintain an
THERMOSTAT
The room thermostat should be located on an inside wall approximately 56" above the floor where it will not be subject to drafts, sun exposure or heat from electrical fixtures or appliances. Follow manufacturer’s instructions enclosed with thermostat for general installation procedure. Color coded insulated wires (#18 AWG) should be used to connect thermostat to unit. Eight conductors are required.
The subbase on the low voltage thermostat includes an "Emergency Heat" position on the system switch and a pilot light. In the "Emergency Heat" position, the thermostat will provide electric resistance heat only. The compressors will not run. The pilot light will indicate that the switch is on "EM HT". Nine conductors are required for this application.
POWER AND CONTROL WIRING
Field wiring to the unit must conform to provisions of the National Electrical Code, ANSI / NFPA No. 70 (in U.S.A.), current Canadian Electric Code (CEC) CSA C22.1 (in Canada) and/or local ordinances. The unit must be electrically grounded in accordance with NEC and CEC (as specified above) and/or local codes. Voltage tolerances which must be maintained at the compressor terminals during starting and running conditions are indicated on the unit Rating Plate.
4 | Unitary Products Group |
