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Step 3 — Mount Mounting Bracket on Wall
1. Decide how refrigerant will be piped. If necessary, knock
out the appropriate pre-punched holes (Fig. 4) on unit for
piping and electrical connections.
2. Remove bracket from fan coil unit by pulling it down
from fan coil unit bottom as shown in Fig. 6.
3. Using a carpenter’s level, fasten mounting brackets into
the studs in the wall at least 10 in. away from the ceiling
with the 8 screws provided. Always be sure to insert screws
into the top 2 holes indicated in Fig. 6. Make sure the
attached bracket will support a 200 lb vertical load. For
a masonry wall, anchor shields can be used to attach bracket
to the wall.
4. Temporarily hang unit on bracket to check location and
level.
If mounting bracket is not mounted level, the indoor sec-
tion will be mounted unevenly, and condensate drain-
age water may drip onto the floor. Also, a gap between
the bracket and the wall may result in vibration and noise
from the indoor section.
5. Mark and cut condensate and piping holes.
a. For piping through the wall, mark the wall below the
condensate connection and cut a 2
1
⁄
2
-in. hole into the
wall at either point ‘‘A’’ or point ‘‘B’’ in Fig. 7.
NOTE: The 2
1
⁄
2
-in hole must be made at a downward slope
to ensure proper condensate drainage. See Fig. 8. Slope
condensate line at a minimum pitch of
1
⁄
4
in. per foot of
line. The condensate line cannot be run up for upper pip-
ing connections − only refrigerant lines may be run up.
b. Push the wall sleeve (factory supplied with the unit)
through the 2
1
⁄
2
-in. wall opening.
Step 4 — Connect Refrigerant Piping —
Fan coil
units may be connected to the outdoor units using field-
supplied refrigerant grade piping. Refer to Tables 4A-4F for
the correct size piping. The length of refrigerant pipe de-
pends on the unit placement and building structure; run pipes
as directly as possible. For piping requirements over 50 ft of
total run, or more than 25 ft of lift, consult the long line
application guidelines available in the product presale lit-
erature, or contact your local representative. For the 38HDS024
unit, the maximum pipe length is 50 ft.
The 40QNB,QNH unit is shipped with a factory hold-
ing charge of R-22. DO NOT BURY MORE THAN
36 IN. OF REFRIGERANT PIPE IN THE GROUND.
If any section of pipe is buried, there must be a 6-in.
vertical rise to the valve connections on the outdoor unit.
If more than the recommended length is buried, refrig-
erant may migrate to the cooler, buried section during
extended periods of unit shutdown, causing refrigerant
slugging and possible compressor damage at start-up.
Use the following instructions to connect piping.
1. Install insulation. Insulate
all
refrigerant lines on heat pumps
and 38HDS systems to prevent condensation. It is ex-
tremely important that all refrigerant lines and the
AccuRater
t
metering device be insulated on heat pumps.
On 38HDC, HDL cooling only units, the liquid line may
be left uninsulated. Use any acceptable heat resistant closed-
cell foam insulation (minimum
3
⁄
8
-in. wall thickness). When
insulating piping, cap ends and slide insulation over the
piping. Insulation can also be cut and placed over piping.
2. Run liquid and gas refrigerant piping.
a. Run pipes as directly as possible, and avoid any un-
necessary turns and bends.
b. Suspend refrigerant pipes so that the insulation is not
damaged and vibrations are not transmitted to the
structure.
c. Leave slack in the refrigerant pipe between the struc-
ture and the unit to absorb vibrations.
Fig. 4 — Refrigerant Piping
*38HDC, 38BK/38HDL/38HDS systems.
Fig. 5 — Maximum Line Lengths
5