MAXIMUM ALLOWABLE
DIFFERENCE (in.)
0.5 | 1.0 | 1.0 |
Fig. 2 — Unit Leveling Tolerances
Step 2 — Field Fabricate Ductwork — Secure all ducts to roof curb and building structure on vertical discharge units. Do not connect ductwork to unit. For horizontal applica- tions,
Ducts passing through an unconditioned space must be in- sulated 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 applica- ble fire codes.
A minimum clearance is not required around ductwork. Cabinet
These units are designed for a minimum continuous return- air temperature in heating of 50 F (dry bulb), or an intermittent operation down to 45 F (dry bulb), such as when used with a night setback thermostat.
Step 3 — Install External Trap for Condensate Drain — The unit’s
When using the standard side drain connection, ensure the plug (Red) in the alternate bottom connection is tight before in- stalling the unit.
To use the bottom drain connection for a roof curb installa- tion, relocate the
All units must have an external trap for condensate drain- age. Install a trap
Step 4 — Rig and Place Unit — Inspect unit for transportation damage, and 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, and rollers may be used to move unit across a roof. Level by using unit frame as a
CONDENSATE PAN (SIDE VIEW)
DRAIN PLUG
NOTE: Drain plug is shown in
Fig. 3 — Condensate Drain Pan
reference. See Table 1 and Fig. 4 for additional information. Operating weight is shown in Table 1 and Fig. 4.
Lifting holes are provided in base rails as shown in Fig. 5. Refer to rigging instructions on unit.
All panels must be in place when rigging and lifting.
POSITIONING — Maintain clearance around and above unit to provide minimum distance from combustible materials, prop- er airflow, and service access. See Fig. 5. A properly positioned unit will have the following clearances between unit and roof curb;
Do not install unit in an indoor location. Do not locate unit air inlets near exhaust vents or other sources of contaminated air.
Be sure that unit is installed such that snow will not block the combustion intake or flue outlet.
Unit may be installed directly on wood flooring or on Class A, B, or C
Although unit is weatherproof, guard against water from higher level runoff and overhangs.
Locate mechanical draft system flue assembly at least 48 in. from any opening through which combustion products could enter the building, and at least 48 in. from an adjacent building. When unit is located adjacent to public walkways, flue assem- bly must be at least 7 ft above grade.
NOTE: When unit is equipped with an accessory flue dis- charge deflector, allowable clearance is 18 inches.
Flue gas can deteriorate building materials. Orient unit such that flue gas will not affect building materials.
Adequate
Flue vent discharge must have a minimum horizontal clear- ance of 4 ft from electric and gas meters, gas regulators, and gas relief equipment.
After unit is in position, remove shipping materials and rig- ging skids.
3
