
7
INSTALLATION
Jobsite Survey
Complete the following checks before installation.
1. Consult local building codes and the NEC (National Elec-
trical Code) ANSI/NFPA 70 for special installation
requirements.
2. Determine unit location (from project plans) or select unit
location.
3. Check for possible overhead obstructions which may
interfere with unit lifting or rigging.
Step 1 — Plan for Unit Location
Select a location for the unit and its support system (curb or
other) that provides for the minimum clearances required for
safety. This includes the clearance to combustible surfaces,
unit performance and service access below, around and above
unit as specified in unit drawings. See Fig. 2 on page 5.
NOTE: Consider also the effect of adjacent units.
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 roof-covering material when roof curb is used.
Do not install unit in an indoor location. Do not locate air inlets
near exhaust vents or other sources of contaminated air. For
proper unit operation, adequate combustion and ventilation air
must be provided in accordance with Section 5.3 (Air for Com-
bustion and Ventilation) of the National Fuel Gas Code, ANSI
Z223.1 (American National Standards Institute) and NFPA
(National Fire Protection Association) 54 TIA-54-84-1. In
Canada, installation must be in accordance with the CAN1-
B149 installation codes for gas burning appliances.
Although unit is weatherproof, avoid locations that permit wa-
ter from higher level runoff and overhangs to fall onto the unit.
Locate mechanical draft system flue assembly at least 4 ft
(1.2 m) from any opening through which combustion products
could enter the building, and at least 4 ft (1.2 m) from any adja-
cent building (or per local code). Locate the flue assembly at
least 10 ft (3.05 m) from an adjacent unit’s fresh air intake
hood if within 3 ft (0.91 m) of same elevation (or per local
code). When unit is located adjacent to public walkways, flue
assembly must be at least 7 ft (2.1 m) above grade.
Select a unit mounting system that provides adequate height to
allow installation of condensate trap per requirements. Refer to
Step 12 — Install External Condensate Trap and Line on
page 15 for required trap dimensions.
ROOF MOUNT
Check building codes for weight distribution requirements.
Unit operating weights are shown in Table 2.
Table 2 — Operating Weights
Step 2 — Plan for Sequence of Unit Installation
The support method used for this unit will dictate different se-
quences for the steps of unit installation. For example, on curb-
mounted units, some accessories must be installed on the unit
before the unit is placed on the curb. Review the following for
recommended sequences for installation steps.
CURB-MOUNTED INSTALLATION
1. Install curb
2. Install field-fabricated ductwork inside curb
3. Install accessory thru-base service connection package
(affects curb and unit) (refer to accessory installation
instructions for details)
4. Prepare bottom condensate drain connection to suit
planned condensate line routing (refer to Step 12 — Install
External Condensate Trap and Line on page 15 for details)
5. Rig and place unit
6. Install outdoor air hood
7. Install flue hood
8. Install gas piping
9. Install condensate line trap and piping
10. Make electrical connections
11. Install other accessories
PAD-MOUNTED INSTALLATION
1. Prepare pad and unit supports
2. Check and tighten the bottom condensate drain connection
plug
3. Rig and place unit
4. Convert unit to side duct connection arrangement
5. Install field-fabricated ductwork at unit duct openings
6. Install outdoor air hood
7. Install flue hood
8. Install gas piping
9. Install condensate line trap and piping
10. Make electrical connections
11. Install other accessories
FRAME-MOUNTED INSTALLATION
Frame-mounted applications generally follow the sequence for
a curb installation. Adapt the sequence as required to suit spe-
cific installation plan.
Step 3 — Inspect Unit
Inspect unit for transportation damage. File any claim with
transportation agency.
Confirm before installation of unit that voltage, amperage and
circuit protection requirements listed on unit data plate agree
with power supply provided.
On units with hinged panel option, check to be sure all latches
are snug and in closed position.
Locate the carton containing the outside air hood parts. Do not
remove carton until unit has been rigged and located in final
position.
Step 4 — Provide Unit Support
ROOF CURB MOUNT
Accessory roof curb details and dimensions are shown in Fig. 3
(on page 8). Assemble and install accessory roof curb in accor-
dance with instructions shipped with the curb.
NOTE: The gasketing of the unit to the roof curb is critical for a
watertight seal. Install gasket supplied with the roof curb as shown
in Fig. 3. Improperly applied gasket can also result in air leaks and
poor unit performance.
48FC--
UNIT LB (KG)
04
05
06
07
Base Unit
482 (219) 543 (246) 556 (252)
607 (275)
Economizer
Vertical
50 (23)
50 (23)
50 (23)
50 (23)
Horizontal
80 (36)
80 (36)
80 (36)
80 (36)
Humidi-MiZer
®
System
50 (23)
50 (23)
80 (36
80 (36)
Cu Fins
25 (11)
43 (20)
56 (25)
56 (25)
Powered Outlet
35 (16)
35 (16)
35 (16)
35 (16)
Curb
14 in. (356 mm)
115 (52)
115 (52)
115 (52)
115 (52)
24 in. (610 mm)
197 (89)
197 (89)
197 (89)
197 (89)