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air pressure in the riser. Pressure testing risers with water
should be done with the unit service valves closed to prevent
flushing debris into the unit valve packages. This will also
allow risers to be drained down after testing in the winter to
avoid freeze-up problems. In the event that leaking or defec
-
tive components are discovered, the sales representative must
be notified before any repairs are attempted. All leaks should
be repaired before proceeding with the installation.
10. After system integrity has been established, pull the riser
insulation back into place over the joint and glue or seal to
prevent sweating and heat loss or gain. Internal chilled water
piping and valves are located over the drain pan and need not
be insulated.
11. If required, fireproof where necessary. Any fireproofing
requirements where risers or piping penetrate floors or walls
are the responsibility of the installer. This work should be
done only after all pressure testing is completed. The fire
-
proofing method used must accommodate pipe expansion
and contraction and the piping must be protected from abra
-
sion and chemical attack. The pipe insulation also must be
maintained to prevent sweating and must be protected from
wear or erosion at the joint between the insulation and the
fireproofing material.
42SUA UNIVERSAL STACK ARRANGEMENT
The unique design of the universal stack fan coil unit allows for
field configuration for each unit. Air discharge, riser, drain, and
outside air knockouts have been strategically located on each unit.
Risers, shown with unit, are for reference only. All risers are facto
-
ry fabricated and shipped loose for field installation.
It is important that you identify all of the unit feature locations and
which knockouts you intend to use before proceeding with the in
-
stallation. See Fig. 18-22. Also, it must be determined whether
your application requires a Mating Unit (primary/secondary) and
its configuration. Consult your local sales representative or the
factory for further details on primary/secondary arrangements.
Potential Universal Arrangement Unit Configurations
Risers: Three Locations
The pre-installed supply, return, and drain risers (2-pipe or 4-pipe
applications) can be oriented on any of three sides of the unit (see
Fig. 18).
NOTE: Risers cannot be installed on the return air side of the
cabinet.
Fig. 18 — 42SUA Unit Configuration
Unit orientation is determined based on the location of the risers in
the building. The riser side of the universal stack unit always de
-
termines the rear of the unit. See Fig. 19.
Fig. 19 — 42SUA Unit Orientation
Return Air: Single Location
The return air/access panel may then be oriented on the left, right,
or front of the unit.
Supply Air: Five Locations (4 sides and top)
Includes stitched design for 1/2 in. (12 mm) duct flanges.
Outside Air: Two Locations
Either side adjacent to the return air opening.
NOTE: Outside air opening may be used on a side if risers are
configured on that same side.
Supply, Return, and Drain Riser Installation
1. Three sides of each universal stack unit have four supply and
return riser knockouts along the center and one drain knock
-
out near the lower part of the unit (see Fig. 20). Identify
whether your application uses a 2-pipe or 4-pipe configura
-
tion.
a. 2-pipe configurations typically use the two inner riser
knockouts.
b. 4-pipe configurations will use all four riser knockouts.
2. Locate and mark the riser and drain knockouts that apply to
your particular unit application, ensuring proper orientation
of the return air opening in room.
3. Insert a flat head screw driver into knockout slot shown in
Fig.
21.
4. Pry screw driver back and forth until knockout tabs break
away from the unit.
5. Discard knockout. Be careful of sharp edges.
6. Use a sharp retractable knife (see Fig. 22) and vertically cut
the insulation down the center of the riser and drain knock
-
outs the full length of the knockout.
7. Use adhesive or glue to re-attach insulation that has pulled
away from the unit during knockout removal process.
42SUA
CABINET
RETURN AIR
HR
CR
D
HS
CS
HR
CR
D
HS
CS
HR
CR
D
HS
CS
D
CR
HS
CS
HR
R
D
S
HR =
HOT WATER RETURN
HS =
HOT WATER SUPPLY
D
=
DRAIN
CR =
COLD WATER RETURN
CS =
COLD WATER SUPPLY
R =
RETURN
D =
DRAIN
S =
SUPPLY
2 or 4-PIPE
REAR
(RISER SIDE)
42SU
CABINET
RIGHT
FRONT
LEFT