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 Table 3 for the
correct size piping. The length of refrigerant pipe depends
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.
DO NOT BURY MORE THAN 36 IN. OF REFRIG-
ERANT 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 rec-
ommended length is buried, refrigerant may migrate to
the cooler, buried section during extended periods of unit
shutdown, causing refrigerant slugging and possible com-
pressor 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 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.
d. Install factory-supplied flare connection and Accu-
Rater metering device in liquid line at the fan coil unit
on 38HDC and 38BK systems (Fig. 9). Make sure the
arrow on the metering device body points
AWAY FROM
the fan coil unit. Use Table 4 to verify that the correct
piston for your system has been shipped with the unit.
Fig. 6 — Bracket Mounting
NOTE: Use either point ‘‘A’’ or point ‘‘B.’’
Fig. 7 — Wall Hole Location for Rear Piping
Fig. 8 — Piping Hole
5