5300477-UIM-A-0317
Johnson Controls Unitary Products
5
DUCTWORK
These units are adaptable to downflow use as well as rear supply and
return air duct openings. To convert to downflow, use the following
steps:
1.
Remove the duct covers found in the bottom return and supply air
duct openings. There are four (4) screws securing each duct cover
(save these screws to use in Step 2).
2.
Install the duct covers (removed in step one) to the rear supply and
return air duct openings. Secure with the screws used in step one.
3.
Seal duct covers with silicone caulk.
Duct work should be designed and sized according to the methods of
the Air Conditioning Contractors of America (ACCA), as set forth in their
Manual D.
A closed return duct system shall be used. This shall not preclude use
of economizers or ventilation air intake. Flexible duct connectors are
recommended in the supply and return duct work to minimize the trans-
mission of vibration and noise.
Refer to Figures 4 and 5 for information concerning rear and bottom
supply and return air duct openings.
FILTERS
Proper filter size is very important. Filter size, type and pressure drop
should always be considered during duct system design.
All 3 phase units include a filter frame kit which is shipped inside the
unit from production. Field installation is required.
A filter rack and high velocity filters are standard on three phase units.
Filters must always be used and must be kept clean. When filters
become dirt laden, insufficient air will be delivered by the blower,
decreasing your units efficiency and increasing operating costs and
wear-and-tear on the unit and controls.
Filters should be checked monthly; this is especially important since this
unit is used for both heating and cooling.
Table 4:
Unit Clearances
,
Direction
Distance (in.)
Direction
Distance (in.)
Top
1
1. Minimum Clearance of 1inch all sides of supply air duct for the first 3 feet
of duct for 20 & 25 kW., zero inches thereafter. For all other heaters, zero
inch clearance all sides for entire length of duct.
36
Power Entry
(Right Side)
36
Side Opposite
Ducts
36
Left Side
24
Duct Panel
0
Bottom
2,3
2. Units must be installed outdoors. Overhanging structures or shrubs should
not obscure outdoor air discharge outlet.
3. Units may be installed on combustible floors made from wood or class A,
B or C roof covering materials.
NOTE: For units applied with a roof curb, the minimum clearance may be
reduced from 1 inch to 1/2 inch between combustible roof curb material
and this supply air duct.
1
NOTES:
NOTICE
All units are shipped in the horizontal supply/return configuration. It is
important to reduce the possibility of any air leakage through the bot-
tom duct covers (resulting from cut, torn, or rolled gasket) due to
improper handling or shipping processes. To ensure a good tight
seal, it is recommended that silicone caulk and/or foil tape be applied
along the cover edges.
CAUTION
When fastening duct work to the side duct flanges on the unit, insert
the screws through the duct flanges only. DO NOT insert the screws
through the casing. Outdoor duct work must be insulated and water-
proofed.
NOTICE
Be sure to note supply and return openings.
!
Model
A
B
C
D
E
F
All
14
13.5
5
3.5
47.5
42
FIGURE 4:
Bottom Duct Dimensions (inches)
Model
A
B
All
13.6
14
FIGURE 5:
Rear Duct Dimensions (inches)
D
16
C
A
B
A
A0343-001
SUPPLY
AIR DUCT
RETURN
AIR DUCT
E
F
1.75
VIEW LOOKING UP
AT BOTTOM OF UNIT
15.6
A
B
A
4.3
A0344-001
6.75
SUPPLY
AIR DUCT
RETURN
AIR DUCT
