48VT-- A
signal words: DANGER, WARNING, and CAUTION. These words are used with the
!WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury or death.
Before installing or servicing system, always turn off main power to system. There may be more than one disconnect switch. Turn off accessory heater power switch if applicable. TAG THE DISCONNECT SWITCH WITH A SUITABLE WARNING LABEL.
!WARNING
FIRE, EXPLOSION, ELECTRICAL SHOCK AND CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal injury, death or property damage.
A qualified installer or agency must use only
!CAUTION
CUT HAZARD
Failure to follow this caution may result in personal injury.
When removing access panels (see Fig. 19) or performing maintenance functions inside your unit, be aware of sharp sheet metal parts and screws. Although special care is taken to reduce sharp edges to a minimum, be extremely careful when handling parts or reaching into the unit.
INTRODUCTION
The
Models with an N in the fifth position of the model number are dedicated Low NOx units designed for California installations. These models meet the California maximum oxides of nitrogen (NOx) emissions requirements of 40 nanograms/joule or less as shipped from the factory and must be installed in California Air Quality Management Districts or any other regions in North America where a Low NOx rule exists.
RECEIVING AND INSTALLATION
Step 1 — Check Equipment
IDENTIFY UNIT
The unit model number and serial number are stamped on the unit information plate. Check this information against shipping papers.
INSPECT SHIPMENT
Inspect for shipping damage before removing packaging materials. If unit appears to be damaged or is torn loose from its anchorage, have it examined by transportation inspectors before removal. Forward claim papers directly to transportation company. Manufacturer is not responsible for any damage incurred in transit. Check all items against shipping list. Immediately notify the nearest equipment distribution office if any item is missing. To prevent loss or damage, leave all parts in original packages until installation.
Step 2 — Provide Unit Support
For hurricane tie downs, contact distributor for details and PE (Professional Engineering) Certificate if required.
ROOF CURB
Install accessory roof curb in accordance with instructions shipped with curb (See Fig. 4). Install insulation, cant strips, roofing, and flashing. Ductwork must be attached to curb.
IMPORTANT: The gasketing of the unit to the roof curb is critical for a water tight seal. Install gasketing material supplied with the roof curb. Improperly applied gasketing also can result in air leaks and poor unit performance.
Curb should be level to within 1/4 in. (6 mm). This is necessary for unit drain to function properly. Refer to accessory roof curb installation instructions for additional information as required.
SLAB MOUNT
Place the unit on a solid, level concrete pad that is a minimum of 4 in. (102 mm) thick with 2 in. (51 mm) above grade. The slab should be flush on the compressor end of the unit (to allow condensate drain installation) and should extend 2 in. (51 mm) on the three remaining sides of the unit. Do not secure the unit to the slab except when required by local codes.
Step 3 — Field Fabricate Ductwork
Secure all ducts to roof curb and building structure on vertical discharge units. Do not connect ductwork to unit. For horizontal applications, unit is provided with flanges on the horizontal openings. All ductwork should be secured to the flanges. Insulate and weatherproof all external ductwork, joints, and roof openings with counter flashing and mastic in accordance with applicable codes.
Ducts passing through an unconditioned space must be insulated and covered with a vapor barrier.
If a plenum return is used on a vertical unit, the return should be ducted through the roof deck to comply with applicable fire codes.
Read unit rating plate for any required clearances around ductwork. Cabinet
Step 4 — Provide Clearances
The required minimum operating and service clearances are shown in Fig. 2 and 3.
IMPORTANT: Do not restrict outdoor airflow. An air restriction at either the
The condenser fan pulls air through the condenser coil and discharges it through the top grille. Be sure that the fan discharge does not recirculate to the condenser coil. Do not locate the unit in either a corner or under an overhead obstruction. The minimum clearance under a partial overhang (such as a normal house overhang) is
Do not place the unit where water, ice, or snow from an overhang or roof will damage or flood the unit. Do not install the unit on carpeting or other combustible materials. The unit may be installed on wood flooring or on Class A, B, or C roof covering materials.
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