Table 1 — System Combinations for Indoor
and Outdoor Units
SYSTEM
INDOOR UNIT
OUTDOOR UNIT
High Wall
Cooling
Only
40QNB018
38HDC,L018
40QNB024
38HDC,L024
(2) 40QNB018
38HDS024*
(4) 40QNB018
38HDS048*
40QNB024, (2) 40QNB018
38HDS048*
(2) 40QNB024
38HDS048*
High Wall
Heat Pump
40QNH018
38BK018
40QNH024
38BK024
*Multi-split systems can accommodate up to 4 fan coil units of vari-
ous types with one condensing unit. The combinations listed in
this table are those which use only high-wall units (not in combina-
tion with any other type of fan coil unit). Refer to system presale
literature or Price Pages for more details.
NOTE: Numbers in ( ) indicate quantities of more than 1. See Fig. 1
for 40QN high wall fan coil unit.
INSTALLATION
The 40QNB high wall fan coil unit is installed with either
the 38HDC,HDL condensing or 38HDS multi-split condens-
ing outdoor unit, and the 40QNH unit is installed with the
38BK heat pump outdoor unit. Refer to Table 1 to make sure
the correct indoor unit(s) is installed with the correct out-
door unit.
Installation instructions for the 40QN fan coil units are
contained in this manual. Refer to this manual for proper
installation of the complete system. Note that the 38HDC,
HDL, and BK outdoor units are shipped with installation and
service instructions for basic installation of the outdoor sec-
tion. Be sure to make the modifications in Make Connec-
tions to Outdoor Unit section on page 13 of this literature,
so that the outdoor unit will operate properly with the 40QN
control system. Be sure the unit will be operated within the
application guidelines shown in Table 2. When installing the
38HDC, HDL, HDS, or BK unit, note that for cooling op-
eration below 55 F (38HDC, HDL, BK), it is necessary to
equip the outdoor unit with the low ambient control acces-
sory. The low ambient control is standard on 38HDS units.
To install this system, you will need:
• 40QNB or QNH fan coil unit(s)* with standard wireless
remote controller
• 38HDC, HDL, HDS, or BK outdoor unit
• low-ambient (38HDC, HDL, BK) or winter start (38HDS)
kit (if required for your application)
* More than one fan coil unit may be used with the 38HDS
multi-split units. Refer to 38HDS system Price Pages for
full details.
NOTE: Refrigerant pipe, drain pipe, wire, etc., are also re-
quired to install unit and are field supplied.
Be sure you have the required parts before beginning in-
stallation. The 40QN unit utilizes a microprocessor control
system to deliver optimum levels of comfort and efficiency.
Be sure to follow these instructions carefully to obtain proper
functioning of the unit.
Step 1 — Complete Pre-Installation Checks
UNPACK UNIT — Store unit in the original packaging
until it is moved to the final site for installation. When re-
moving unit from carton, lift by its 4 corners. Also, note that
there is a plastic bag containing mounting screws taped to
the mounting bracket.
INSPECT SHIPMENT — Upon receipt of shipment check
unit (Fig. 1) for damage. Forward claim papers directly to
the transportation company. Manufacturer is not responsible
for damage incurred in transit.
Table 2 — Application Ranges
COOLING MODE
Maximum
Minimum
Indoor
Unit
Outdoor
Unit
Indoor
Unit
Outdoor
Unit
95 F DB
115 F DB
67 F DB
55 F DB*
71 F WB
57 F WB
0° F DB†
HEATING MODE (38BK Systems Only)
Maximum
Minimum
Indoor
Unit
Outdoor
Unit
Indoor
Unit
Outdoor
Unit
80 F DB
75 F DB
55 F DB
0° F DB
71 F WB
65 F WB
LEGEND
DB
— Dry Bulb
WB — Wet Bulb
*38HDC, HDL and BK systems only.
†38HDS systems only.
NOTE: Unit may be equipped with a low-ambient control (HDC, HDL,
BK) or winter start kit (HDS) that will allow operation down to −20 F.
Check all items. See Table 3. If any item is missing notify
your Carrier distributor. To prevent loss or damage, leave all
parts in original packages until installation.
Step 2 — Select Location —
Consult local building
codes and NEC for special installation requirements.
There are several ways the unit may be installed to dif-
ferent types of wall construction. These instructions do not
cover all installation methods. As a typical installation, these
instructions focus primarily on mounting the unit to wall studs
in new construction. See Fig. 2 for unit dimensions and
Fig. 3 for required clearances. Plan your installation care-
fully before you begin. Listed below are some guidelines that
should be followed when determining location for the unit.
1. Center unit (horizontally) on the wall selected.
2. Place the unit so it faces normal location of room
occupants.
3. Allow sufficient space for airflow clearance, wiring, re-
frigerant piping, and servicing unit. See Fig. 2 and 3.
4. Select walls that are:
a. Strong enough to support weight of the unit.
b. Accessible to convenient condensate drainage.
c. Free of obstacles that may block air circulation to the
fan coils.
d. Outside walls (if possible) to make piping easier.
5. Place top of fan coil unit as high on the wall as possible
making sure the unit is at least 10 in. down from ceiling
to permit proper air intake. Also, make sure that the unit
is not placed directly over anything to prevent filter re-
moval or block airflow.
6. Make sure units are easily accessible to electrical power.
7. Refrigerant piping can enter the unit through the prepunched
holes. Refrigerant piping can run up or down along the
wall, to the right or left along the wall, straight through
the wall, or into the wall (Fig. 4). Once the piping is through
the wall, it can run inside walls, in ceilings, between floors,
or straight to the outside. See Fig. 5 for maximum line
lengths.
NOTE: Run refrigerant piping as directly as possible, and
avoid any unnecessary turns or bends.
8. Condensate piping can be directed through the inside wall
to an approved drain, or directed straight outside.
NOTE: The piping hole for condensate line must be made
at a downward slope to ensure proper drainage. See Mount
Mounting Bracket on Wall Section on page 5 for details.
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