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18-BB38D1-1D-EN
Table 1. Vibration Isolators/Snow Feet Locations
Note:
These views represent the base as
viewed looking up from underneath
the unit.
Important:
Unit requires vibration isolator
support in the general areas
shown. Locate 3/4" thick
vibration isolators on the
bottom of the basepan as
illustrated by black dots for
ground level pad applications.
Modify vibration isolator
location as necessary for frame
and rail applications.
Small Cabinet
****4024 - 4036
Medium Cabinet
****4042 - 4060
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For rooftop applications using field fabricated frame
and ducts use the following procedure:
1.
Locate and secure the frame to the roof by bolting
or welding. Three (3) sleeper rails are required. One
on each end to support the edges of the unit and
one across the center of the unit. The center rail
must run inside both drip lips. Vibration isolators
should be installed as indicated in
,
adjust as necessary for your sleeper rails. The
isolators must be placed on base pan, not drip lip.
Add flashing as required. Flashing must conform to
local building codes.
2. Prepare the hole in the roof in advance of installing
the unit.
3. Secure the horizontal or down airflow ducts to the
roof. Refer to the previous Convert from Horizontal
Airflow to Down Airflow section if conversion is
needed.
4. All fabricated outdoor ducts should be as short as
possible.
5. Place the unit on the frame.
6. The unit must be mounted level for proper drainage
of water through the holes in the base pan.
7. Secure the unit to the frame.
8. Insulate any ductwork outside of the structure with
at least two (2) inches of insulation and then
weatherproof. There must be a weatherproof seal
where the duct enters the structure.
9. The unit should not be exposed to direct roof water
runoff.
10. Flexible duct connectors must be of a flame
retardant material. All duct work outside of the
structure must be insulated and weatherproofed in
accordance with local codes.
11. Access and service clearances for the unit must be
given careful consideration when locating the duct
entrance openings. See unit dimensions.
12. Continue with the following installation sections to
complete the installation: Ductwork, Filter, and
Electrical Wiring.
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For roof top applications using field fabricated ducts
and sleeper rails rather than a curb or frame, use the
following procedure:
1. Locate and secure the sleeper rails to the roof by
bolting (three (3) rails required). One on each end to
support the edges of the unit and one across the
center of the unit. The center rail must run inside
both drip lips. Vibration isolators should be
installed, adjust as necessary for your sleeper rails.
The isolators must be placed on base pan, not drip
lip. Add flashing as required. Flashing must
conform to local building codes.
2. Prepare the hole in the roof in advance of installing
the unit.
3. Secure the horizontal or down airflow ducts to the
roof. Refer to the previous Convert from Horizontal
Airflow to Down Airflow section if conversion is
needed.
4. All fabricated outdoor ducts should be as short as
possible.
5. Place the unit on the rails.
6. The unit must be mounted level for proper drainage
of water through the holes in the base pan.
7. Secure the unit to the rails.
8. Insulate any ductwork outside of the structure with
at least two (2) inches of insulation and then
weatherproof. There must be a weatherproof seal
where the duct enters the structure.
9. No exposure to direct roof water runoff.
10. Flexible duct connectors must be of a flame
retardant material. All duct work outside of the
structure must be insulated and weatherproofed in
accordance with local codes.
11. Access and service clearances for the unit must be
given careful consideration when locating the duct
entrance openings. See unit dimensions.
12. Continue with the following installation sections:
Ductwork, Filter and Electrical Wiring.
