Applied Comfort NFWC Series User manual

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NFWC SERIES UPFLOW PACKAGED TERMINAL AIR CONDITIONER (PTAC)
Cooling with Hot Water or Steam Heating
INSTALLATION & OPERATION MANUAL
IMPORTANT:
READ AND SAVE THESE INSTRUCTIONS. INSTALLATION AND WIRING MUST
BE IN ACCORDANCE WITH CEC, NEC AND LOCAL ELECTRICAL CODES.

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GENERAL INFORMATION
This model NFWC Applied Comfort PTAC is designed
and built for through-the-wall installation in either new
or existing buildings. The self contained compressor
and refrigerant system delivers the cooling, and the
tube-and-fin heat exchanger in the subbase provides the
heating by hot water or steam sources.
WARNING: To avoid property damage, bodily injury
or death, ensure power is disconnected before any
service is attempted. Repairs should be made by
qualified service personnel only. The chassis must be
installed in accordance with the Authority Having
Jurisdiction, and all Local and National Codes,
including the National Electrical Code, and the
Canadian Electrical Code, as applicable.
FOR EFFICIENT OPERATION
Air Filter
The washable air filter is not shipped with the chassis –
it is shipped installed in the heating subbase. Operating
the unit without an air filter will void the warranty.
Keep air filter clean. The air filter can be removed and
cleaned with soap and water. Inspect and clean the
filter a least once a month or more often as conditions
dictate. Replace as necessary. A dirty, clogged filter
reduces the efficiency of the system. It can also cause
erratic performance of controls and can result in
damage to the motor and compressor.
ATTENTION: An improperly maintained air filter or
not using an air filter at all will void the warranty. The
unit must not be used for temporary heating or cooling
during the building’s construction stage.
To access the air filter, first remove the grille cover
from the heating subbase by rotating the two ¼ turn
finger and thumb fasteners until the grille cover
releases. The unit front panel need not be removed. The
air filter is located directly below the heat exchange
coil and slides out freely. Always replace the grille
cover after re-inserting the filter.
CAUTION: Risk of bodily injury. Be aware that the
heating coil, valve, and piping may be extremely hot
and can potentially cause burns even if the unit is not in
operation, due to residual heat. Always replace the
grille cover after re-inserting the filter before operating
the unit.
Clean Coils
As part of regular servicing, clean the condenser coil,
and evaporator coil at least annually, or more often as
dictated by the severity of the particulates and
pollutants circulating in the outdoor and indoor
operating environments. One suggested method is as
follows:
Unimpeded Outdoor Airflow
Do not block off the outside air flow to the unit. The
condenser air inlet and outlet must be free of
obstructions and of any external influence that would
cause the hot discharged condenser air to be re-
circulated back into the outdoor blower intake. Outdoor
air is drawn into the outdoor blower on the left side of
the rear grill (viewing grille). Hot condenser air is
forced sideways out of the right hand portion of the
rear grill, minimizing air re-circulation back into the
blower intake. Paper, leaves, dirt, or other material
blocking airflow, or fouling the condenser coil surface,
can impair efficiency and cause serious damage to the
compressor.

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Oiling
The motors are permanently lubricated; no re-oiling.
Unimpeded Indoor Airflow
Ensure that drapes, bed, bedspread, and furniture etc.
do not block the indoor air discharge and intake air
openings, causing a restricted air flow through the
indoor air handling section of the unit. Do not place
articles on discharge grille – especially liquids.
Reducing Load
To reduce the cooling load, draw drapes or blinds in
the summer, to reflect direct rays from the sun.
To reduce the cooling and heating load, keep windows
and doors closed when operating the unit.
WALL SLEEVE CONSIDERATIONS:
The wall sleeve must be installed in strict accordance
with the wall sleeve installation instructions, supplied
with the wall sleeve. For compatibility with the heating
subbase, the bottom front edge of the wall sleeve must
penetrate into the room by at least 0.875 inches past the
finished wall surface, and the bottom of the sleeve must
be between 8.2 and 9.2 inches off the finished floor.
IMPORTANT: The wall sleeve must be installed so that
the bottom of the sleeve has a 1/8” per foot slope
downward toward the outside to ensure proper water
drainage out the back edge of the sleeve during overflow
conditions. The specified slope corresponds to a 1/8
bubble on a carpenter’s level. The wall sleeve must also
be level from side-to-side.
HEATING SUB-BASE
The heating subbase contains a tube-and-fin heat
exchanger that is configured for the use with hot water
or steam as the heating medium. The subbase also
houses the field-supplied electrical receptacle and
provides mechanical protection for the cord and plug.
The subbase measures 8” high without leveling feet,
and with the leveling feet allows adjustability from 8.2
to 9.2” high off the finished floor surface.
Electrical and plumbing rough-in can be done either
through the back of the heating subbase or through the
openings provided in the bottom of the subbase.
Telescoping Side Channels
Telescoping side channels close in the gap between the
subbase and the wall. The further the wall sleeve
penetrates into the room, the larger the gap to fill will
be. The side channels have slotted holes and are
reversible to enable practically infinite adjustability
within the range from zero to 10.75 inches of gap fill,
without having to cut or break off any sections.

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Adjust the side flanges as follows:
Measure the penetration of the bottom of the wall
sleeve into the room relative to the finished wall
surface, and record as “x”. Remove the grille cover
from the heating subbase by rotating the two ¼ turn
finger and thumb fasteners until the grille cover
releases. The total side length of the heating subbase
(cover removed) plus side channel closure is calculated
as 7.5 + “x”. Insert the side channels and secure with
the screws provided, set at the total side length
calculated. Center the subbase under the wall sleeve
opening and adjust the levelling feet to the anticipated
correct height. Final height adjustment can be made
after the wall sleeve is permanently installed. At that
point, the flanges of the side channels can be screwed
to the finished wall from inside the subbase if desired,
to anchor the entire heating subbase assembly in place.
The bottom of the wall sleeve will end up overlapping
the subbase by about 0.875 inches.
Plumbing Connections:
The heating coil is supplied with 5/8” O.D. (actual
diameter) copper tubing connections. Hot water heating
typically requires a Normally Open (NO) water valve, and
steam usually requires a Normally Closed (NC) steam
valve. The NFWC unit 24 VAC control output to the
valve is factory set for NC but can be field-converted to
NO duty as described in Section Heating/Cooling Chassis
Installation.
Remove the cover plate on the right hand side of the
heating coil to provide better access to the copper
connection tubes. Always pipe the valve to the supply
connection. If the heating medium is hot water, connect
the valve “outlet” (Supply) to the lower connection and
the Return water to the upper connection. If the heating
medium is steam, connect the valve “outlet” (Supply) to
the upper connection and the Return to the lower
connection. Route the steam or water source to the valve’s
“inlet” connection.
Install the piping, valve, and accessories (as specified by
the design engineer) in the space available under the
heating coil.
ELECTRICAL WIRING AND RECEPTACLE
Wire Sizing
A single outlet branch circuit from the main electrical
panel to the receptacle in the subbase should be used.
Wire sizing shall be in accordance with the minimum
circuit ampacity as declared on the unit Rating Plate for
the specific chassis. Wire sizing must also take into
account any distance from fuse box or breaker panel to
receptacle to prevent excessive voltage drop in
undersized wires.
IMPORTANT: Low voltage to the unit will cause
compressor starting problems and decrease the
performance and reliability of the compressor.
Branch Circuit Protection
The Current Rating of branch circuit protection using a
Time Delay Fuse or HACR circuit breaker should also
be as declared on the unit Rating Plate for the specific
chassis being installed.
Plug and Receptacle
All 230-208 Volt units are normally furnished with a
NEMA 6-20P, 20 Amp non-locking plug, and hence
will require a NEMA 6-20R receptacle to be installed
in the heating subbase.
All 115 Volt units are furnished with a NEMA 5-15P,
or 5-20P non-locking plug as applicable. The
respective plug will require a NEMA 5-15R or
combination 5-20R receptacle to be installed in the
heating subbase.

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All 277 Volt units are furnished with a NEMA 7-20P,
20 Amp non-locking plug, and hence will require a
NEMA 7-20R receptacle to be installed in the heating
subbase.
NOTE: These installations are not “cord connected”
units; they are permanently connected per the National
Electrical Code. The plug and cord are considered to be
a “connector of convenience” in order to facilitate easy
removal of the chassis for servicing. The plug and cord
are suitably protected within the heating subbase.
WARNING: To avoid property damage, bodily injury
or death, the unit must be used on a grounded power
supply only. The unit will be grounded through the
service cord plug and matching receptacle as long as
the branch circuit remains grounded.
DO NOT:
Change the length of the cord.
Bend the connector blades or otherwise alter
service cord plug configuration.
Use extension cords.
Wiring to Subbase
Remove the junction box cover plate. Punch out
the appropriate knock-out and anchor the electrical
supply conduit to the junction box. Connect the
power supply wires to the receptacle. Be sure to
properly ground the electrical supply to the
subbase and the receptacle using the two Green
with Yellow Stripe ground leads provided. Mount
the receptacle with the designated screws and re-
install the junction box cover plate.
CHASSIS INSTALLATION
Unpack heat/cool chassis from shipping carton.
Check for any shipping damage. Spin the fan wheels
manually to confirm free rotation. Inspect refrigerant
piping to ensure there is no damage or potential
chafing. Report any shipping damage to the carrier
immediately.
Check the interior of the installed wall sleeve. Clean
out any dirt or debris that may have accumulated.
Replace any air seals that are damaged or missing, if
applicable.
Heating/Cooling Chassis Installation
1. Locate the wall sleeve seal shipped with the unit and
apply it to the top front flange of the wall sleeve,
running even with the bottom edge of the flange (see
illustration).
2. Slide the chassis into the wall sleeve until firmly
seated against the seals. Push from the ends of the
front cover where they attach to the coil supports. Be
careful NOT to push the chassis from the electrical
box cover or middle of the front coil cover.
3. The chassis must be level from side-to-side and
sloped toward the outdoors from front-to-rear in the
order of 1/8 inch per foot, once the chassis side
flanges are drawn up tight to the wall sleeve using the
four flange screws. A chassis slope downward
(backward toward the room) from outdoor-to-indoor
side is not permissible and must be corrected before
the unit is operated.
4. There are vertical air seals at the rear of the unit that
surround the condenser outlet that will engage and
“seal” against the rear grille. However, in some cases,
such as when an extra deep wall sleeve is used, or
some other variation is encountered that prevents the
air deflectors from sealing against the outdoor grille,
then steps must be taken to add anti-recirculation
baffles to prevent hot condenser air from short-
circuiting back into the air intake/outdoor blower inlet
via the void space created in behind the outdoor grill.
5. Position the chassis in the wall sleeve cabinet and
slide into place. Keep the chassis level, square, and
centered to prevent binding. The chassis must be
pushed into the wall sleeve until the side flange seals
of the chassis engage the sleeve. Alternately tighten
each of the four draw screws until the chassis is
drawn snugly into the sleeve. Do not over-tighten the
draw screws.

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6. Locate the 24 Volt wiring harness either coiled
beneath the control box or shipped loose with the
unit. The harness is used to make connections to the
aquastat. It is also employed if a remote 24 Volt AC
wall thermostat will be used. Connect the multi-wire
24 volt wiring harness to the mating plug protruding
beneath the control box, as applicable, and follow the
detailed instructions on the wiring diagram affixed to
the specific unit being installed. Insulated crimp-on
connectors are provided at the end of every
connection lead to facilitate connections/insulation. If
an aquastat will be not be used, you must connect
the ends (blue/orange) of the aquastat leads
together to permanently complete the aquastat
circuit.
7. A 24 VAC water or steam valve output connector is
also provided under the control box. A mating
connector and 3 feet of wire leads are supplied to
connect to a 24 VAC valve. The units can
accommodate a normally-open NO or a normally-
closed NC valve. The NO/NC switch is located in the
high voltage wiring compartment as a DIP switch on
the electronic control board, and is factory set to NC.
The setting can be changed to NO in the field by
qualified service personnel.
WARNING: The NO/NC conversion procedure
involves exposure to high voltage electrical circuits in
the control box in order to make the necessary change
to the DIP switch, and must be performed by qualified
service personnel. Failure to do so could result in
property damage, personal injury or death. Disconnect
electric power to the unit before servicing.
8. Locate the indoor air thermistor bulb at the end of the
black thermistor wire with clamp coiled beneath the
control box. The bulb and clamp must be relocated to
the thermistor holder in the bottom of the heating
subbase so it is sure to sense true return air
temperature, and not air that has been heated by the
heating coil. Use the clamp provided to secure the
bulb in place.
IMPORTANT: To avoid damaging the indoor
thermistor wire, always remove the thermistor from the
clamp holder before removing the chassis for service.
IMPORTANT: Operating the unit without the filter in
place can damage the unit, and void the warranty.
Always remember to re-install the filter after servicing
the chassis, or replacing/cleaning the filters.
9. Wipe unit cabinet/wall sleeve to remove dirt, etc.
10. The unit is now ready for operation, when supplied
with power from the distribution panel and wired to a
remote thermostat (if applicable).
START-UP CHECKLIST
Note: Once the unit is installed, it should be checked
for proper function by qualified service personnel
before turning it over to the User.
Circuit breakers, wire size, and electrical
connections tight and correct
Filter clean and properly in place
Condenser air inlet and outlet free of
obstructions and no short-circuiting of
condenser air
Unit operated for 20 minutes to prove stability
Controls operation OK
Unit installed in compliance with all codes and
ordinances
All panels in place and secured with required
fasteners
Mylar overlay applied to cover up touch pad
for 24 Volt Remote Thermostat installations.
Work area clean and free of debris
Owner or operator instructed on control
operation and routine maintenance.
USER CONTROLS - GENERAL
NFWC series is available with advanced-function
electronic controls with membrane switch type keypad.
ELECTRONIC CONTROLS
The chassis incorporating electronic controls is factory-
shipped with an active keypad control and display
mounted directly to the control panel. The unit
functions are controlled by the user by pressing the
keys on the keypad, and reading the display. However,
the unit also has the latent ability to be field-converted

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by qualified service personnel for use with a field-
supplied 24 volt AC wall thermostat. These instructions
will address both unit-mounted control operation, and
remote 24 volt AC wall thermostat operation.
CONTROL AT THE UNIT, KEYPAD/DISPLAY
THE KEYPAD CONTROL
Become familiar with the keypad keys as shown in
Figure 1.
Display
Red light emitting diodes (LEDs) display the actual
temperature of the air entering the unit at floor level.
The display can also be used to indicate the desired set
point temperature for room comfort. It is important to
remember that the temperature displayed is the
temperature sensed at the unit’s indoor air inlet and can
be significantly different from the bulk room
temperature at a distance from the unit.
On/Off Key
Each press of the key toggles the unit from an OFF
state to an ON state or from an ON state to an OFF
state. Heating and cooling functions, as well as the
display, and all indicating LEDs except for the fan
indicators, are enabled or disabled with this key. When
toggled OFF, the control preserves only two modes
active; fan-only, and room freeze protection.
Fan Key
Each press of the Fan Key cycles the fan through three
modes of operation; Low Speed, High Speed and Auto.
Small green LEDs will indicate the mode. The On/Off
key need not be ON to operate the fan and set fan
speeds. Auto Mode will cycle the fan on and off, and
determine the fan speed, in conjunction with the
heating or cooling demand.
Warmer Key
Pressing the Warmer Key will cause the display to
show the set point temperature for 3 seconds, and then
increases room temperature by 1 degree for every
subsequent press of the key.
Cooler Key
Pressing the Cooler Key will cause the display to show
set point temperature for 3 seconds, and then decreases
room temperature by 1 degree for every subsequent
press of the key
°F/°C Key
This key toggles the display between Fahrenheit and
Celsius temperature modes, and affects all displayed
temperatures.
Heat Key
The Heat Key toggles the unit in and out of heating
mode for every press of the key, provided the On/Off
Key is ON.
Cool Key
The Cool Key toggles the unit in and out of cooling
mode for every press of the key, provided the On/Off
Key is ON.
Figure 1
OPERATION USING KEYPAD
When the unit is first plugged in, or when recovering
from a power outage, there will be a random 5 to 15
second delay before the electronic control powers up.
This minimizes the large electrical surge that would
otherwise occur if all units in a building started up at
the same time.
To Initiate Heating or Cooling Mode
Press On/Off Key to turn on the LED display and
commence full functionality. Push the °F/°C Key to
obtain the desired temperature scale. Press the Heat or
Cool key as applicable, and the current indoor
temperature will be shown on the display.

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Set Desired Temperature
Press Cooler or Warmer key as applicable. Each push
of the key increases or decreases the set point
temperature by 1 degree, as applicable.
Set Fan Mode
Press Fan key to cycle through the fan settings as
indicated by the small green circular LEDs. Select
continuous High Speed fan, continuous Low Speed fan,
or Intermittent Fan by selecting Auto. Auto cycles the
fan on and off with the calls for heating or cooling.
Auto also sets fan speed according to the amount of
heating or cooling demanded. In Auto mode, the fan
will start up periodically to establish airflow; air
temperature will be sampled, and then the fan will shut
off again if there is no demand.
Disable Heating or Cooling, but Initiate Fan-Only
Press On/Off key to turn off LED display. Press Fan
key to cycle through the fan settings as indicated by the
small circular LEDs. Select continuous High or Low
speed. Do not select Auto, as it will turn the fan off.
CONTROL AT THE WALL THERMOSTAT
CONVERSION TO 24V REMOTE
THERMOSTAT
Except for the wall thermostat and thermostat cable,
everything is included with the unit to field convert a
keypad-operated unit to 24 Volt AC wall thermostat
operation by qualified service personnel. Specific
conversion instructions are detailed on the wiring
diagram affixed to each particular unit to be converted.
Conversion involves accessing the high voltage wiring
compartment and changing a DIP switch setting on the
electronic board. Once the DIP switch setting has been
changed, operation will be in remote thermostat mode
as soon as power is restored to the control.
WARNING: The conversion procedure involves
exposure to high voltage electrical circuits in the
control box in order to make the necessary change to
the DIP switch, and must be performed by qualified
service personnel. Failure to do so could result in
property damage, personal injury or death. Disconnect
electric power to the unit before servicing.
A factory-supplied 24 Volt wiring harness is provided
with every unit to facilitate connection to the wall
thermostat wiring. One end has a multi-pin connector
which mates with a connector exiting the unit. The
other end has preinstalled butt splice connectors, which
play a dual role in insulating any unused connectors,
and can also be used to make the wire connections for
wires that are used.
The final step is to apply the masking label provided, to
cover up the keypad. The keypad and display will be
disabled and no longer be available for control. The
masking label markings instruct the user to go to the
wall thermostat for controlling the unit.
COMPATIBLE THERMOSTATS
The features of the 24 VAC wall thermostat chosen
will dictate the extent of the features available from the
unit.
Electric Heat / Cool units can accommodate the
following thermostats in either manual or automatic
changeover:
Single Stage Heat/Cool, Single Speed Fan
Single Stage Heat/Cool, Two Speed Fan
Note: The thermostat selection must be verified to
ensure its control logic will always energize a Fan
output (G) on a call for heat – also known as an
Electric Heat Type Thermostat.
General:
All the above can have single speed or two speed fan
control.
The wiring diagrams affixed to the units will guide the
specific connection strategies for the particular
thermostats used.
THERMOSTAT LOCATION:
Proper functioning of the thermostat depends on
accurate room temperature sensing. Be conscious of
locating the thermostat where temperatures near the
thermostat are not representative of room temperature.
For example, do not install the thermostat where it is
subjected to direct sunlight, other sources of heat, or to
cold drafts, including air discharged from a supply air
register. A common error is forgetting to seal the hole
in the wall where the thermostat cable passes through,
directly behind the thermostat body. Air bleeding from
behind the wall can drastically affect the temperature
sensed by the thermostat.

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REMOTE THERMOSTAT OPERATION
When the unit is first plugged in, or when recovering
from a power outage, there will be a random 5 to 15
second delay before the electronic control powers up.
The keypad will be totally disabled once the DIP
switch has been set for remote mode. The unit will
obey the commands from the thermostat only.
The thermostat will automatically maintain the
temperature in the room, based on the setting pre-set by
the user. If the thermostat has only single fan speed
capability, a decision will need to be made as to
whether the fan will always run in high speed or low
speed, and then the appropriate fan speed wiring
connection can be made at the unit.
All the internal control features of the electronic board
remain active, except for keyboard and display
interface functions and room temperature sampling.
Room temperature is detected at the location of the
wall thermostat, and is usually a much more accurate
representation of bulk room temperature. The
thermostat used may have advanced features beyond
the basic functions described below. Consult your
thermostat Installation and Operating Instructions for
further information.
In addition to controlling room temperature, the room
thermostat is also used to select whether the unit is to
be in heating mode, or cooling mode, or in automatic
changeover between the modes. It also determines
whether the system is to be ON or OFF, and whether
the fan is to run continuously, or to cycle with heating
or cooling demand.
Figure 2
Once a comfortable temperature setting is established,
no other adjustments are necessary, except for fan
speed, which may or may not be adjustable on your
particular thermostat.
CAUTION: One side of the unit’s 24-volt control system
is grounded. When wiring the thermostat, care must be
taken not to ground the wires, or drive a nail through the
thermostat wire bundle, thereby potentially burning out
the transformer.
WALL THERMOSTAT OPERATION
Heat Sets the unit into heating mode.
Initiates heating when room
temperature falls below set point.
Off Disables heating and cooling
modes, but allows control of fan.
Cool Sets the unit into cooling mode.
Initiates cooling when room
temperature rises above set point.
Auto
(not shown) Found on automatic changeover thermostats only. Allows the
thermostat to decide whether it
should be in the heating or cooling
mode. Usually a 4 Fdifferential
or “deadband” will exist between
heating and cooling set points to
prevent inadvertent rapid
switching between modes.
Temperature
Setting Establishes the “set point”, or
desired room temperature.
Fan On Synonymous with “Fan
Continuous”. Fan will continue to
run after the heating and cooling
function has cycled off. Fan will
continue to run even when mode
switch is in Off position.
Fan Auto Synonymous with “Fan
Intermittent”. Fan will cycle on
and off with the heating cycle or
cooling cycle, and will not operate
between cycles.
ADDITIONAL FEATURES:
Some additional features of the Electronic Control
units are as follows:

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Room Freeze Protection
This feature is enabled when the unit is shipped from
the factory. The feature can be disabled by qualified
service personnel. If power is available to the unit, and
regardless of whether it is turned ON or OFF, the unit
will automatically supply heat to the room with the fan
running at low fan speed if the room temperature falls
to 50°F (10ºC). The heat will turn off when the room
temperature reaches 55°F (13ºC). For the feature to
work, the unit must be configured with an electric
heater. The feature is enabled whether the unit is
configured for keypad or remote thermostat. The
protection remains active when the unit is OFF, for
either keypad or remote thermostat application, as long
as the unit is plugged in, power is available, and a heat
source is configured in the unit and is working.
Compressor Short-Cycle Protection
If the electronic control shuts the compressor down for
any reason, a 3 minute time delay will elapse before the
compressor is allowed to re-start. This prevents
compressor overload during re-start due to unequal
system refrigerant pressures.
Indoor Coil Freeze Protection
Control of frost on the evaporator coil due to low
indoor loads, or cold outdoor ambient temperatures, is
provided.
Low Outdoor Temperature Lock-out
If the outdoor temperature is too low for proper
compressor operation, cooling operation will be
suspended until the outdoor temperature rises to an
acceptable point, depending on the application.
Indoor Temperature Limiting (Keypad Control
Only)
Using the keypad control and display, high and low
temperature limits can be established to prevent the
user from entering set point temperatures colder or
warmer than what the property manager or hotel
operator may desire. The temperature limit choices are
as follows:
Configuration Code Low Limit °F
(ºC) High Limit °F (ºC)
R1 63 (17) 86 (30)
R2 65 (18) 86 (30)
R3 65 (18) 90 (32)
R4 67 (19) 88 (31)
R5 67 (19) 92 (33)
R6 69 (20) 90 (32)
R7 69 (20) 72 (22)
The procedure to set the limits is as follows:
Depress the On/Off key, the °F/°C key, and the
Warmer key simultaneously for 5 seconds to enter the
limit setup mode. The Warmer and Cooler keys will
scroll through the R-values indicated in the above
table. Once the desired R-value has been obtained on
the display, press the On/Off key to accept the change,
and then press it again to effect the change and restore
the normal display.
Automatic Powered Damper
NFWC models are available with or without provision
for fresh air. However, if the units are configured to
bring in fresh air, they must have an automatic powered
fresh air damper that opens the fresh air door to bring
outdoor air into the room only when the indoor blower
is running. If the indoor fan shuts off, the damper
automatically closes and interrupts the heating coil’s
potential exposure to possible extremely cold air when
there is no blended air flow over the coil and/or no
flow of the heating medium inside the coil. The factory
default is fresh air with high speed fan operation only,
but it can be changed to open with low speed fan
operation only by having qualified service personnel
re-wire the unit as shown on the specific wiring
diagram affixed to the unit.
WARNING: The speed conversion procedure involves
exposure to high voltage electrical circuits in the
control box in order to make the necessary change to
the damper action tied to motor speed, and must be
performed by qualified service personnel. Failure to do
so could result in property damage, personal injury or
death. Disconnect electric power to the unit before
servicing.
OPTIONAL AIR DUCT KIT:
The NFWC series has been designed and certified
for use with an optional external duct kit. It is
recommended that only the Applied Comfort
Products duct kit be installed on the unit.
The NFWC has been designed to use a 4.5” tall by
7.5” wide insulated (3/8” insulation) Duct Plenum
fastened to the top of the unit, which connects to a
maximum 48” long insulated (1/4” insulation)
Extension Duct of the same size, and uses an Air
Terminal Grille at the end of the Extension Duct
having an actual outlet area of 7.25”x 4.25” with

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.125” thick non-adjustable louvers (all provided in the
kit). To ensure proper operation it is important that
all installation instructions shipped with the duct
kit are strictly followed. What is presented in these
instructions is a basic overview only.
The Duct Plenum is designed to be reversible
(shown with right discharge) and is permanently
capped at one end. A decision is made whether to
duct right or left and the Duct Plenum is
positioned with the opening directed accordingly.
A strip of blank-off plates (not shown) is supplied
with the kit to allow the installer to snap off and
adjust the number of active plates required to
divert a given amount of air to the adjacent room
via the Extension Duct.
Using the maximum number of plates to restrict
the plenum outlet opening results in a 60%
physical blockage that will divert up to up to 50%
of the total air flow to the adjacent room.
To preserve the intended functionality of the
design, do not attempt to add additional
restriction to exceed the 60% maximum
amount of blockage. The detailed installation
instructions shipped with the duct kit will provide
more detail regarding percent air diversion relative
to number of plates used.
To install the Duct Plenum, the Discharge
Grille/Control Door assembly must first be
removed from the Chassis Air Outlet by removing
the screw located under the control door.
The Duct Plenum can now be installed. Insert the
Duct Plenum tabs into the slots provided in the
Chassis Enclosure based on the direction you
require the air discharge. On the opposite end of
the tabs there will be an existing screw location.
Use the screw removed previously to secure the
Duct Plenum to the Chassis Air Outlet.
Lay the desired number of blank-off plates into the
Duct Plenum in accordance with the kit
installation instructions. Re-install The Discharge
Grille/Control Door assembly that was removed
from the Chassis Air Outlet so that the control
door is above the touchpad controls, and secure
using the screw provided in the kit. The Discharge
Grille/Control Door assembly should now reside
in the Duct Plenum outlet if the installation was
done correctly.
To complete the assembly, cut the 48” Extension
Duct to the desired length, slide it on to the
protruding flanges of the Duct Plenum outlet and
secure with the two beige screws provided, and
then terminate the duct with the Air Terminal
Grille by fastening it to the wall in the adjacent
room.
To give full access to remove the Chassis at a later
date, the Discharge Grille/Control Door assembly
can be removed with a single screw to give access
to the Duct Plenum, and the Duct Plenum can be
removed with a single screw by pulling slightly
upward and sideways on the capped end, once the
two beige screws have been removed from the
duct extension.