SLAB MOUNT (Horizontal Units Only) Ð Provide a level concrete slab that extends a minimum of 6 in. beyond unit cabinet. Install a gravel apron in front of condenser coil air inlet to prevent grass and foliage from obstructing air¯ow.
NOTE: Horizontal units may be installed on a roof curb if required.
Step 2 Ð Field Fabricate Ductwork Ð Secure all ducts to roof curb and building structure on vertical units. Do not connect ductwork to unit. For horizontal applica- tions,
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 ap- plicable ®re codes.
A minimum clearance is not required around ductwork. Cabinet
These units are designed for a minimum continuous return- air temperature of 50 F (dry bulb), or an intermittent opera- tion down to 45 F (dry bulb), such as when used with a night
Step 3 Ð Install External Trap for Condensate
Drain Ð The unit's
When using the standard side drain connection, make sure the plug in the alternate bottom connection is tight before installing the unit.
To use the bottom drain connection for a roof curb in- stallation, relocate the
bottom connection to the side connection. See Fig. 4. The piping for the condensate drain and external trap can be com- pleted after the unit is in place.
All units must have an external trap for condensate drain- age. Install a trap at least
Step 4 Ð Rig and Place Unit Ð Inspect unit for trans- portation damage. File any claim with transportation agency. Keep unit upright and do not drop. Spreader bars are not required if top crating is left on unit. Rollers may be used to move unit across a roof. Level by using unit frame as a ref- erence. See Table 1 and Fig. 6 for additional information. Operating weight is shown in Table 1 and Fig. 6.
Lifting holes are provided in base rails as shown in Fig. 6 and 7. Refer to rigging instructions on unit.
All panels must be in place when rigging.
POSITIONING Ð Maintain clearance around and above unit to provide minimum distance from combustible materials, proper air¯ow, and service access. See Fig. 7.
Do not install unit in an indoor location. Do not locate unit air inlets near exhaust vents or other sources of con- taminated air.
Be sure that unit is installed so that snow will not block the combustion intake or ¯ue outlet.
Unit may be installed directly on wood ¯ooring or on Class A, B, or C
Although unit is weatherproof, guard against water from higher level runoff and overhangs.
Position unit on roof curb so that the following clearances are maintained:
Fig. 1 Ð Horizontal Conversion Panels
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