Emerson PFH020A-L, User Manual

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Site Preparation and Installation
Liebert
®
Mini-Mate2
™
34
5.5 Centrifugal Condenser Fan Installation
The self-contained, air-cooled model utilizes a centrifugal blower in a housing that attaches directly to
the right end of the ceiling unit. Mounting holes are pre-cut at the factory and fasteners are provided.
In addition, a wiring harness is included for the power and control connections required from the
ceiling unit to the blower. Route capillary tube from fan speed controller through hole in ceiling unit.
Screw end of capillary tube on to access valve in discharge line. Providing ductwork for outdoor air
to/from the condenser is optional.
5.5.1 Electrical, Control and Power Connections
Field connections are required at the ceiling unit using the provided wiring harness. A four-wire
connection is required from the condenser fan to the ceiling unit. Route the conduit through the hole
provided in the left side of the cabinet.
If a field-supplied disconnect switch is installed, mount it on the ceiling unit but not on any removable
panels.
NOTICE
Risk of punctured refrigerant lines. Can cause sudden loss of refrigerant and cooling.
During mounting of external disconnect switch, take special care that no refrigerant lines are
punctured or damaged.
The ceiling unit power connections are made at the terminal block or disconnect switch in the lower
left-hand corner of the electric panel (middle). The power terminal connections are labeled L1 and L2.
(For 208VAC applications, change the input transformer connection as described in the electrical
schematic attached to cabinet). Self-contained, air-cooled models require power connections from the
evaporator ceiling unit to the condenser fan (See Figures 12 and 22 and provided electrical
schematic).
NOTICE
Risk of incorrect input power supply. Can cause equipment damage.
The line voltage supplied must correspond with the voltage specified on the unit’s nameplate.
5.5.2 Indoor Condenser Fan Ductwork
The total external static pressure for the inlet and outlet ducts, including grille, must not exceed
0.5 inches of water. Hood intake dimensions should be the same as the condensing unit duct
dimensions. The duct connection provided for air flow to the ceiling unit 7-1/2" x 16-3/4" (191mm x
425mm). The duct opening for air flow from the condenser fan is 12" x 12" (305mm x 305mm).
Ductwork should be designed for 950 CFM (1614 CMH).
If the unit draws air from the outside of the building, rain hoods must be installed. In addition, install
a triple-layer bird screen over rain hood openings to eliminate the possibility of insects, bird, water
and debris entering the unit. Use flexible ductwork or nonflammable cloth collars to attach ductwork
to the unit and to control vibration transmission to the building. Attach the ductwork to the unit
using the flanges provided. Locate the unit and ductwork so that the discharge air does not short
circuit to the return inlet. Avoid directing the hot exhaust air toward adjacent doors or windows.
Normal operating sound may be objectionable if the unit is placed directly over quiet work areas.
Ductwork that runs through a conditioned space or is exposed to areas where condensation may occur
must be insulated. Whenever possible, ductwork should be suspended using flexible hangers. Avoid
mounting the duct directly to the building's structure. In applications where the ceiling plenum is
used as the heat rejection domain, the discharge air must be directed away from the air inlet and a
screen must be added to the end of the discharge duct to protect service personnel. For multiple unit
installation, space the units so that hot exhaust air is not directed toward the air inlet of an adjacent
unit.