Airmark GFT Series User manual

IO-123163 Effective 01-14-2016 1
INSTALLATION GUIDE
1. Safety Instruction
!WARNING
Potential safety hazards are alerted using the following symbols. The symbol is used in conjunction with terms
that indicate the intensity of the hazard.
This symbol indicates a potentially hazardous situation, which if not avoided,
could result in serious injury, property damage, product damage or death.
Certied technicians or those individuals
meeting the requirements specied by
NATE may use this information. Property
and product damage or personal injury hazard may occur
without such background.
Disconnect ALL power sources prior to
servicing. Failure to do so may cause
personal injury or property damage.
Product designed and manufactured
to permit installation in accordance
with local and national building codes.
It is the installer’s responsibility to ensure that product is
installed in strict compliance with national and local codes.
Manufacturer takes no responsibility for damage (personal,
product or property) caused due to installations violating
regulations. In absence of local/state codes, refer to National
Electric Code: NFPA 90A & 90B Uniform Mechanical Code.
When this unit is installed in an enclosed
area, such as a garage or utility room with
any Carbon Monoxide producing devices
(i.e. automobile, space heater, water heater etc.) ensure that
the enclosed area is properly ventilated.
The unit is designed for operation with
120V, single phase, 60 Hz power supply.
Aspen will not be responsible for
damages caused due to modication of the unit to operate
with alternative power sources.
Unit is not approved for outdoor
installations.
This symbol indicates a potentially hazardous situation, which if not avoided,
may result in moderate injury or property damage.
Only factory authorized kits and
accessories should be used when
installing or modifying this unit unless it is
so noted in these instructions. Some localities may require
a licensed installer/service personnel.
CAUTION
!
CAUTION
!
!WARNING
!WARNING
!WARNING
!WARNING
!WARNING
!WARNING
GFT/GFS Series - Cased/Uncased
Ceiling Mount Hydronic Heat Dx Cool
Air Handler
2. Introduction
The GFS/T Series air handlers are versatile horizontal ceiling mount
units. These air handlers have the following standard features:
Louvered ceiling access panel has separate frame that attaches to
ceiling joists. Solid access panel available for use with end return
installations. Compatible with most brands of air conditioners or heat
pumps.
I. Application Versatility
II. Motor
Constant torque EC motor allows motor speed control with embedded
software. Blowers are mounted on a plate so they can be easily
removed for service.
III. Cabinet (GFT Only)
Sturdy, fully insulated galvanized steel cabinet with painted front
panels. Knockout for duct return.
IV. Electronic Circuit Board
Electronic circuit board provides 30 secs ON/OFF blower time delay,
extracting more heat/cool from the coil.
V. DX Coil
High efciency ried copper tubes/enhanced aluminum ns provide
maximum heat transfer. All coils immersion tested at 500 psi then
nitrogen pressurized and factory sealed for maximum reliability.
Liquid-line Schrader allows pre-installation pressure testing.
Available with either orice or TXV metering device. Field-installable
bolt-on TXVs are also available. Primary & secondary condensate
drain. All drain connections are 3/4” MPT. Access door allows for coil
cleaning. Certied for use with either R22 or R410a.
VI. Warranty
One year limited parts warranty.

2IO-123163 Effective 01-14-2016
4. Installation Preparation
Read all the instructions in this guideline carefully while paying
special attention to the WARNING and CAUTION alerts. If any of
the instructions are unclear; clarify with certied technicians. Gather
all the tools needed for successful installation of the unit prior to
beginning the installation.
If the unit is to be installed in garages, warehouses or other areas
where they may be subjected to physical damage, adequate
protective barriers must be installed. Unit shall be installed 18” away
from source of ignition.
If the unit is located in high humidity areas like attics or unconditioned
garages; the air handler casing might experience nuisance sweating.
In such installation scenarios, wrapping the casing with a 2” berglass
insulation with vapor barrier shall be used.
The drain lines must be installed with ¼” per foot pitch to provide free
drainage. A condensate trap MUST be installed on the primary drain
line to ensure proper drainage of the condensate. The trap must be
installed in the drain line below the bottom of the drain pan (Fig.
4D-1)
Since coil is upstream of the blower, all
drains MUST be trapped or sealed. Failure
to do so will result in condensate overow
from the drain pan. Aspen will NOT be responsible for any
damages resulting from failure to follow these instructions.
CAUTION
!
Ductwork for air conditioning systems should be installed in
accordance with standards of the National Fire Protection Association
Pamphlet No. 90A or 90B, and also be sized in accordance with
National Environmental System Contractors Association Manual K,
whichever is applicable.
On any job, non-ammable exible collars should be used for the
return air and discharge connections to prevent transmission of
vibration. Although these units have been specially designed for
quiet vibration-free operation, air ducts can act as soundboards, and
if poorly installed, amplify the slightest vibration to the annoyance
level.
All main supply and return air drops should be properly size as
determined by the designer of the duct system and should not
necessarily be the size of the duct ange openings of the unit. When
installing a central air return grille in or near the living space, it is
advisable to design the ductwork so that the grille is not in direct
line with the opening in the unit. The use of one or two elbows and
acoustical duct liner will also ensure quieter system operation.
It is recommended that wherever supply and return air sheet metal
duct pass through unconditioned areas, they be insulated to prevent
excessive heat loss during heating operation. When applied in
conjunction with summer air conditioning, sheet metal duct routed
through unconditioned areas should be insulated and have an
outside vapor barrier to prevent formation of condensation.
The drain pan has primary (white) and secondary (red) drain
connections. If a secondary drain line is required, it should be run
separately from the primary and should terminate in a highly visible
location. Condensate disposal through the secondary drain line
indicates that the primary drain line is plugged and needs cleaning. If
a secondary drain line will not be provided, plug the secondary drain.
Drain plugs are NOT to be reused without plumbers tape or putty.
The drain line connectors should be hand tightened to a torque of
approximately 35-40 lb (4-5 turns).
Fig 4A-1. Air Handler Dimensions
Fig 4D-1. Condensate Drain Trap
3. Inspection
üOn receiving the product, visually inspect it for any major shipping
related damages. Shipping damages are the carrier’s responsibility.
Inspect the product labels to verify the model number and options
are in accordance with your order. Manufacturer will not accept
damage claims for incorrectly shipped product.
Drain lines from the auxiliary drain pan
should NOT be connected to the primary
drain line of the coil.
CAUTION
!
If the drain pan is constructed of nylon
or plastic, use Teon tape to connect the
drain lines to the threads in the drain pan.
DO NOT USE SOLVENT-BASED PIPE DOPE. THIS WILL
REDUCE THE LIFE OF THE PAN.
CAUTION
!
The GFT series of horizontal ceiling mount air handlers are designed
for zero clearance installation on the sides and back.
4A. Clearances
4B. Installation Options
4C. Condensate Drain
4D. Ductwork
ENCLOSURE DIMENSIONS
UNIT MODEL A” B” C”
GFT 18-24 51-3/4 36-7/8 40
GFT 30-36 66-1/2 48-7/8 55

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5. Installation
Ensure that the unit is adequately sized.
The tonnage of the outdoor unit should
never exceed the tonnage of this unit.
CAUTION
!
The coil was manufactured with a dry
nitrogen pre-charge. Release the pressure
through the Schrader valve test port prior
to installation. If holding pressure is not present, return coil
to distributor for exchange.
!WARNING
Some Aspen coils may include a Schrader
valve on the suction manifold. Ensure
that the Schrader valve and valve core
(where present) are protected from heat during brazing and
installation to prevent leakage. Use a core removal tool to
temporarily remove the core when brazing. Replace the core
once brazing is completed.
CAUTION
!
6. Air Handler Orientation
ü Clean coil ns with degreasing agent or mild detergent and rinse
ns clean prior to installation.
üThe refrigerant line sizes should be selected according to the
recommendations of the outdoor unit manufacturer.
üCare must be taken to ensure all connection joints are burr-free
and clean. Failure to do so may increase chances of a leak. It is
recommended to use a pipe cutter to remove the spun closed end of
the suction line.
üTo reduce air leakage, rubber grommets may be present where
the lines pass through the coil case. To avoid damage, remove
grommets prior to brazing by sliding over the lines. Use a quenching
cloth or allow the lines to cool before reinstalling the grommets.
ü Use of wet rags/quenching cloth is highly recommended to prevent
weld-related damages to the casing and Schrader valve (if present).
1. Using a 5/16” nut driver, remove the hex screws holding the
control panel cover. Remove the control panel cover, disconnect the
fan motor wiring, and remove the blower assembly.
2. Using a 5/16" nut driver, remove the hex screws securing the
heater/AC coil assembly to the slide brackets. The slide brackets are
located on the left and right sides of the assembly.
3. Slide the heater/AC coil assembly out of the brackets and
remove.
4. Mount the enclosure to the ceiling joists through the four mounting
holes using four lag screws.
5. Ensure the unit is level to allow for proper condensate drainage.
6A. Mounting
The unit has pre-drilled holes for ceiling mounting.
To facilitate an easier installation, the blower/fan and heater/AC coil
assemblies are removed prior to mounting the enclosure.

4IO-123163 Effective 01-14-2016
7. Connecting Ducting
8. Metering Devices/Liquid Line Connection
1. Secure the supply air ducting to the duct ange of the air handler.
Canvas connectors are recommended for reducing potential noise
transmission.
Aspen coils are available with two kinds of metering devices a)
owrator or b) TXV. The following instructions are separated into
sections by metering device.
2. A ducted return requires a non-louvered panel.
1. A bottom return installation requires a louvered panel.
3. Both louvered and non-louvered panels are mounted to the ceiling
using screws.
7B. Bottom Return
1. To connect return air ducting to the air handler, remove the
knockout on the rear side of the enclosure to install the ducting.
7A. Remote/Ducted Return
6. Reinstall the components removed prior to mounting the enclosure.
Fig 8A-1. Flowrator assembly components
8A. Flowrator Coils

IO-123163 Effective 01-14-2016 5
Note: Photos are for basic illustration purposes only. Actual
equipment conguration may differ from that shown.
Use Piston sizes recommended by the
outdoor unit manufacturer whenever
possible. The piston should be sized
according to the capacity of the outdoor unit.
CAUTION
!
Failure to install the proper piston can
lead to poor system performance and
possible compressor damage.
!WARNING
I. Installation
I-1. Disassemble owrator
body using two wrenches
and unscrewing with a
counterclockwise motion.
I-3. Slide the attachment nut onto
the liquid line stub out.
I-4. Braze the stub-out portion to the liquid line and let cool.
I-6. Tighten the nut to a torque of approximately 10-30 ft-lbs. Do NOT
overtighten the nut. Overtightening will impede the piston movement
during operation.
I-5. Taking care that the white
Teon seal is still in place inside
the owrater body, rmly seat the
stub and screw the attachment
nut to owrater body.
Be aware of the Teon O-ring. Be sure to
replace the O-ring to attain a proper
seal. (The Teon O-ring is located between
the two halves of the owrator)
CAUTION
!
I-2. Replace the Teon O-ring
(located between the halves).
Discard Schrader if present.
During some installations, a piston change may
be required. If so, the installer MUST change
the piston. Use piston sizes recommended by
the outdoor unit manufacturer. If a sizing chart is
not available, use the piston size chart provided
below to size the required piston. The size of the
piston is stamped on the piston body (Fig 8A-2).
II. Piston Replacement
Fig 8A-2
Use the chart below when matching coil with an outdoor unit with a
different nominal capacity than the coil.
Note: Photos are for basic illustration purposes only. Actual
equipment conguration may differ from that shown.
II-4. Slide the 13/16” nut over
the lineset and separate the two
halves of the owrator.
II-1. Evacuate the system as per manufacturer guidelines and
recommendations
II-2. Turn the 13/16” nut once to release any residual pressure in the
coil.
II-3. After ensuring that the coil
is free of any residual pressure,
disassemble the owrator body
completely using two wrenches.
Take great care not to distort the
feeder tubes. The wrench used
to clasp the nut should be turned
in counter-clockwise direction to
unscrew the nut.

6IO-123163 Effective 01-14-2016
Be aware of the Teon O-ring. Be sure to
replace the O-ring to attain a proper
seal. (The Teon O-ring is located between
the two halves of the owrator)
CAUTION
!
Pay close attention to the piston
orientation. The pointed end of the piston
MUST go into the distributor body, towards
the coil. Failure to ensure this orientation will cause the
piston to be bypassed during operation which might
damage the outdoor unit.
CAUTION
!
II-6. Replace the piston with one
of the correct size. Do not force
the new piston into the body.
Make sure the piston moves
freely in body.
II-7. Assemble the two halves correctly and ensure that the white
Teon O-ring is present between the two halves (See I-5). Slide the
13/16” nut onto the distributor body.
II-8. Tighten the nut to a torque of approximately 10-30 ft-lbs. Do NOT
overtighten the nut. Overtightening will impede the piston movement
during operation.
II-9. If present, slide the rubber grommet back to position to prevent
air leakage.
8B. TXV Coils
Ensure that the TXV selected is compatible
with the refrigerant used in the outdoor
system (R22 or R410A). TXV caps are
painted green for R22 or pink for R410A. In absence of color,
the caps will be marked with the compatible refrigerant.
CAUTION
!
The sensing bulb and TXV body MUST
be protected from overheating during
brazing. The sensing bulb and TXV body
must be covered using a quench cloth or wet cloth when
brazing. Pointing the brazing ame away from the valve and
sensing bulb provide partial protection only.
!WARNING
Fig 8B-1. Components of a typical TXV assembly
The valves should be sized according to
the capacity of the outdoor unit. Failure
to install the right valve can lead to poor
performance and possible compressor damage.
CAUTION
!
Ensure that the TXV bulb is in direct
contact with the suction/vapor line. Gap
between the bulb and tube should be
avoided. Failure to do so will impair the proper functioning
of the TXV valve.
CAUTION
!
I. TXV Bulb Horizontal Mounting
The orientation and location of the TXV bulb has a major inuence
on the system performance.
It is recommended that the TXV bulb be installed parallel to the
ground (on a horizontal plane). The bulb position should be above and
between 4 o’clock and 8 o’clock. Fig. 8B-2 shows the recommended
position for the TXV bulb installation in the horizontal plane.
The TXV sensing bulb SHOULD be mounted on the suction line
approximately 6” from the TXV or coil housing using the metal clamp
provided. In order to obtain a good temperature reading and correct
superheat control, the TXV sensing bulb must conform to ALL of the
following criteria:
1. The sensing bulb MUST be in direct and continuous
contact with the suction line.
2. The sensing bulb should be mounted horizontally on
the suction line.
3. The sensing bulb MUST be mounted above and between
the 4 and 8 o’clock position on the circumference of the
suction line.
4. The sensing bulb MUST be insulated from outside air.
A properly mounted sensing bulb will prevent false readings caused
by liquid refrigerant that may have formed inside the suction/vapor
line. Insulation will protect the sensing bulb from false readings due
to contact with warm air.
Fig 8B-2. Recommended location for horizontal TXV bulb mount
II-5. Pull the piston out using
a small wire or pick. Verify the
piston size (size is typically
stamped on the body of the
piston - Fig 8A-2). If a different
piston size is required by the
outdoor unit manufacturer,
replace the piston using the small
wire provided with the piston kit.

IO-123163 Effective 01-14-2016 7
If the TXV sensing bulb is mounted
vertically, the capillary MUST be directed
upwards. The bulb must be mounted on
the wall opposite to that being directly hit by the refrigerant
and oil leaving the distributor tubes.
CAUTION
!
II. TXV Bulb Vertical Mounting
Fig 8B-3. Recommended location
for vertical TXV bulb mount
The TXV sensing bulb should
be mounted in a horizontal
plane in relation to the suction/
vapor line. However, some
installation congurations
may require that the sensing
bulb be mounted vertically.
In this instance, place the
bulb opposite the piping wall
being hit by refrigerant and
oil leaving the distributor
tubes, and with capillary tubes
directed upwards as shown in
Fig. 8B-3.
Note: Photos are for basic illustration purposes only. Actual
equipment conguration may differ from that shown.
III. Field-Installed TXV Retrot
When installing an expansion valve, it is not necessary to slide the
coil out of the housing.
III-1. Inspect the TXV box to conrm that the valve is compatible
with the refrigerant in the system.
Male
(Inlet) Female
(Outlet) III-2. Remove the valve from
the box and note the location
of the inlet side (threaded
male port) and the outlet side
(female swivel nut port).
III-5. Braze the stub-out portion to the liquid line and let cool.
III-4. Slide the attachment nut onto the liquid line stub out
(See 8A, I-3)
Do not attempt to touch brazed joints
while hot. Severe burns may result.
!WARNING
III-3. After ensuring that the
Teon O-ring seal is still in place
inside the owrator body, screw
the female swivel nut onto the
owrator body.
III-6. Remove the additional
Teon O-ring seal from the box
and place on the shoulder just
inside the TXV inlet port. Screw
the nut attached to the stub-out
portion of the owrator body onto
the inlet port of the TXV.
A. Remove the valve stem from
the Schrader port mounted on the
suction line.
III-7. Tighten all connections taking care to use proper back up.
III-9a. Some Aspen coils come with a Schrader valve on the suction
line. If a Schrader port is present:
III-8. Remove the valve identication sticker from the valve and
place it adjacent to the Aspen model number on unit name plate.
For disassembly and piston removal refer to section 8A-I.
B. Screw are nut on TXV
equalization tube on to the
Schrader valve stem.
III-9b. In some cases, a suction line schrader port may not be
present. If a Schrader port is NOT present:
When handling or manipulating the
equalizer tube, take great care not to kink
or make extreme bends in the tubing.
CAUTION
!
A. Install a eld-supplied braze-on schrader
valve like that shown on the suction line near
the intended sensing bulb mounting location.
Follow valve manufacturer instructions and
recommendations for installation.
B. Attach equalizer tube to valve as described in
section III-9a above.
III-10. Mount the sensing bulb as described in section 8B-I or 8B-II.

8IO-123163 Effective 01-14-2016
9. Connecting Refrigerant Lines
1. Release nitrogen holding
charge by depressing the
Shrader Valve at the liquid line
connection on the air handler.
If no gas releases from the
air handler, contact distributor
regarding potential leak.
2. Cut off Shrader Valve tting at
the liquid line connection. Use a
tubing cutter for this step. Clean
the burr from the cut tubing to
reduce the chance of future
leaks. Connect the liquid line to
the tubing at the indoor unit.
3. Use a tubing cutter to remove
the spun end from the suction
line connection at the air
handler. Clean the burr from the
cut tubing to reduce the chance
of future leaks.
4. To avoid heat damage to grommets where present, remove these
prior to brazing by sliding them over the refrigerant lines and out of
the way.
5. Check to determine if the
evaporator coil has a Shrader
tting on the suction manifold.
If yes, remove the valve core
to prevent heat damage during
brazing. Replace the valve core
once the piping has cooled.
6. If the air handler has a TXV metering device, remove the sensing
bulb from the suction line prior to brazing to prevent heat damage
from occurring. Replace the sensing bulb once the piping has cooled.
7. Flow nitrogen through the piping when brazing.
8. Braze both refrigerant line connections using proper brazing
procedures.
9. When all line connections are brazed, perform a proper system
evacuation procedure per the outdoor unit manufacturer instructions.
10. Seal the penetration openings where the lineset piping enters the
air handler cabinet.
1. Following outdoor unit manufacturer instructions and
recommendations, charge the system with dry nitrogen to a maximum
pressure of 150 PSIG.
3. If any leaks are discovered, relieve system pressure and repair
leaks. Repeat steps 1-3.
4. With no leaks or weak connections present, evacuate the system
and charge as per the outdoor unit manufacturer instructions and
specications.
10. Leak Check
2. Check all brazed and screw-
on line connections by applying a
soap solution to the joint. A leak
will produce bubbles in the soap
solution.
11. Electrical Installation
These units are designed for a single phase 120VAC, 60 Hz power
supply. Wire selection and wiring must be in accordance with the
National Electric Code and/or local codes. Unit terminals are
designed to accommodate copper or aluminum wiring. If aluminum
wiring is used, please observe special precautions relative to sizing,
wire connections and corrosion protection.
Fig.11-1 shows the typical electrical connections.
Line voltage wiring should be routed through the access holes at
the side of the air handler. Proper electrical conduit connection
ttings should be used. Connect the power wiring to the line side
connections on the air handler. The electrical ground wire should
be connected to the grounding lug. Ensure both the eld supplied
ground wire and air handler GREEN ground wire are both secured
to the grounding lug of the air handler (Fig 11-2).
Fig. 11-1
Fig. 11-2

IO-123163 Effective 01-14-2016 9
Fig 11-3.
11A. Single Stage Cooling
During cooling mode operation, indoor blower wire “G” will energize
a time delay relay located on the control board inside the air handler.
After a short time delay period, the time delay relay will apply 120VAC
to the motor via the “MTR“ terminal. (See Schematic Fig 20-1.) Fan
time delay periods are 30 seconds ON delay and 120 seconds OFF
delay.
The Y wire from the thermostat is not connected at the air
handler. This wire goes directly to the outdoor unit 24 volt wiring
to turn on the outdoor condensing unit when a call for cooling
takes place. The 24 volt common for the outdoor unit circuitry
is connected at the air handler brown wire. (See Fig 11-1.)
The hydronic heater low voltage wiring terminal “W” is wired directly
from the thermostat to the air handler. The indoor blower, on a call for
heat, will ON delay for a period of 5 seconds. When the call for heat
has been satised, the indoor blower will have an OFF delay time
period of 60 seconds.
Operating CFM based upon each speed tap number is shown on
the electrical wiring diagram of the unit. Final air volume adjustments
should be made by referencing total external static pressure (Table
11A-1).
Table 11A-1.
120VAC 24VAC (Fig 11-3).
Transformer
11B. Heating
The unit ships with a micro-processor based board
which controls the electrical functioning of the unit. An
inspection of the controls is recommended prior to startup.
Fig.11-C1 provides a schematic of the control board present in the
unit. The unit ships from the factory with the aquastat jumper in the
OFF position (right two pins) and the heating selector in the HW
position (right two pins). If an aquastat is used in the application; the
jumper should be changed to the ON position (left two pins).
Note: Terminals T and N located on the top right side of the board are
not intended for eld use and should be left disconnected.
11C. Jumper Placement
The aquastat (AQ) jumper must be in the
OFF position at all times, except for when
an aquastat is used. If the jumper is moved
to the ON position without installing an aquastat, the blower
will not be energized.
CAUTION
!
11D. Pump/Valve/Boiler Wiring
Fig.11C-3
The freeze protection sensor is connected to the “FP” and “R“
terminals. This sensor is normally open and will close when the
sensor detects a temperature of less than 40ºF. The pump will
operate and stay ON for a minimum of 30 seconds.
The board has a built-in timer which circulates hot water 6 times a
day for 60 seconds to prevent the hydronic coil from freezing.
11E. Freeze Protection Sensor Wiring
On units shipped from the factory with a pump installed (Fig 11C-3),
the pump will be energized on a call for heat.
On units that were shipped without factory installed pumps, two
black wires should be connected to the terminals marked “BOILER”
T T (see Fig 11C-1). In applications where a boiler provides the hot
water supply, these wires should be connected to the boiler control
wiring. Terminals “BOILER” T T are normally open dry contacts.
In applications where a valve or pump is used to regulate the
hot water supply, the two black wires located on the “BOILER” T
T terminals should be removed and placed on the two terminals
marked “VALVE”. These wires should be connected to a 24V valve
or pump relay according to local requirements and instructions of the
valve or relay manufacturer.
On a call for heat, 24V will be sent to the eld-installed valve or pump
relay, the valve will open or pump relay will close contacts allowing
the pump to run. Water will circulate through the water (hydronic) coil
for 60 seconds prior to energizing the blower. After the thermostat is
satised, the blower will continue to stay energized for a minimum of
30 seconds. The additional blower run time helps maximize heating
efciency.
The air handler uses a 120VAC
to 24VAC step-down transformer.
Fig.11-C1
BLOWER DATA
UNIT
MODEL RPM AMP VOLT HP
CFM VS. STATIC PRESSURE
0.1 0.2 0.3 0.4 0.5
GFS/T
18-24 1625 7.0 120
1/2 680 620 560 490 430
800 730 670 600 530
GFS/T
30-36 1/2 (X2) 1150 1070 990 900 800
1270 1180 1100 1000 900
Add .05 static when enclosure and/or ceiling panel are used. GFS/T 30 and 36 have two motors and four blowers.

10 IO-123163 Effective 01-14-2016
1. Bring airow up to the maximum CFM possible according to Table
11A-1.
2. Evacuate refrigeration system to micron level required by outdoor
unit manufacturer.
14. System Charging
An improperly charged system may cause
degradation in system performance and
damage the compressor. After installation
of the coil, refer to the outdoor unit manufacturer for charging
techniques and amount of charge. If outdoor unit manufacturers
charging instructions are unavailable, then refer to instructions
below to charge the system.
CAUTION
!
14B . Expansion Valve Coils
Add refrigerant until the subcooling measured at the outdoor unit
liquid line matches the subcooling recommendation of the outdoor
manufacturer (typically 7º – 10º F). If chart is unavailable refer to
Table 14B-1.
Table 14B-1
14A . Flowrator Coils
Add refrigerant until the superheat measured at the outdoor unit
suction/vapor line matches the superheat listed in Table 14B-1.
3. Release system charge from outdoor unit and call for cooling.
4. Use outdoor unit equipment manufacturer specic charging charts
if available and make proper charge adjustment based upon outdoor
unit instructions.
5. If outdoor unit instructions and charts are not available, use Aspen
provided charts. Make certain indoor air temperature is near comfort
level setpoint of 75°F prior to establishing superheat and subcooling
levels.
12. Condensate Drain
1. Select desired condensate drain openings according to air handler
orientation. Both Primary and Secondary outlets can be used.
2. Pipe condensate system using proper PVC ttings.
3. Ensure a minimum 2” trap is installed in the condensate drain.
Locate the trap near to the connection opening on the air handler.
See illustration.
1. Select a speed tap from the CFM table and connect appropriate
motor lead wire to the “MTR“ terminal on the control board.
2. Call for fan only operation at the thermostat.
3. Read the external static pressure level on the Magnehelic gauge.
4. Make speed tap selection change to get the air volume as close
as possible to the required level.
5. If the static pressure is above .5” wc, excessive turbulence
or duct friction needs to be reduced. (Obstructions in the
duct system can also cause excessive static pressure.)
6. When proper air volume is established, move on to the charging
procedure.
13. Air Volume Adjustment
Air volume needs to be set to the level recommended by the outdoor
unit equipment manufacturer. Most systems will require around 400
CFM of indoor air for every 1 ton of system cooling capacity. The air
volume must be set prior to attempting system charge.
Use a Magnehelic Gauge with a 1” scale and two static pressure
tips to measure the static pressure during the air volume adjustment
procedure. The high port static pressure tip should be placed in the
supply duct near the outlet of the air handler.

IO-123163 Effective 01-14-2016 11
15. Adjustment of Heat Anticipator
After all connections are made, start-up and checkout must be
performed before proper evaluation of the entire system can be
made. Make sure that heat anticipator is properly set as noted
on thermostat instructions. Load requirements can vary in each
residence and it may be necessary for the installer or homeowner
to make slight adjustments to the heat anticipator setting for longer
or shorter cycles. It is recommended to change the setting no more
than plus or minus 0.05 amps at a time. Greater changes can cause
the unit to rapid cycle or remain on excessively.
7. Check the pump to ensure proper operation. The water inlet of the
unit should be hot if the water temperature in the water heater has
reached the set point. If water is not being circulated through the coil
but the pump is running, then open the air bleed valve in the unit and
purge any air left in the system.
8. Adjust the water heater thermostat so that the water temperature
entering the hot water coils is 120 – 180ºF depending on the amount
of heat required by the structure. This is done with the unit energized
and operating long enough for all temperatures to stabilize.
After all connections are made, start-up and check-out must be
performed before proper evaluation of the entire system can be
made. Make sure that heat anticipator is properly set as noted on
thermostat instructions.
Load requirements can vary in each residence and it may be
necessary for the installer or homeowner to make slight adjustments
to the heat anticipator setting for longer or shorter cycles. It is
recommended to change the setting no more than plus or minus 0.05
amps at a time. Greater changes can cause the unit to rapid cycle
or remain on excessively. To properly check the unit’s operation,
the installer should have an electrical current measuring device
(0-10 amp Amprobe, Fluke), air pressure measuring device (0-1.0
in slope gauge), and a temperature-measuring device (0-200ºF
thermometer).
Install the Amprobe to measure blower current, the slope gauge to
measure static air pressure at the units and the temperature device
to measure unit supply and return air temperature. Before taking
measurements, be sure that all registers, grilles and dampers are
open or are set to their proper positions. Be sure that clean lters
are in place. Temperature measuring device must be installed
to obtain average temperature at both inlet and outlet. For outlet,
measure temperature of each main trunk at a location far enough
away to avoid heater radiation and read the average temperatures.
Table 16-1 below shows the CFM that should be achieved at various
external static pressures.
Purging The System
1. Open air vent and allow water heater to ll with water. Close air
vent when water heater is full and all air has been purged.
2. Ignite water heater. Set thermostat on water heater to 140 degrees.
3. Close the valve on the hot water supply from the water heater (“A”)
and open the valve on the cold water return to the water heater (“B”).
Then open the air vent in the fan coil. Use bucket or hose to discard
water during purging process at air bleed valve. Purge air completely
from line.
4. Once air is purged, close return valve (“B”) and open supply valve
(“A”). Purge the coil and lines of air completely.
5. After air is purged from the system and lled with water, open the
return valve (“B”). Then close the air vent in the fan coil.
6. Apply power to the fan coil and set the room thermostat on heat.
Raise the temperature setting to activate the circulating pump
16. Start-Up
The hot water (hydronic) coil and all
water lines MUST be purged of air
prior to starting the pump. Failure to
do so could result in pump damage. Aspen will not be
responsible for any property or personnel damage caused
by failure to follow this instruction.
!WARNING
Hot water owing to the coil should be
in the range of 120º - 180º F. Water at
these temperatures can cause rst-
degree burns. Use of proper safety gear while installing
or servicing the equipment is strongly recommended
as is installation of a water-tempering valve (for
water temperatures of above 140ºF) to supply lower
temperature water to xtures in the house. N170L series
or equivalent should be used.
!WARNING
Connect the hydronic coil to the water heater system as shown in Fig
16-1 and 16-2. Use exible piping and insulate all pipes. Plumbing
must be in compliance with state or local codes (Code CMR248
in Massachusetts). The units for hydronic heat have different top
and heater box congurations. This conguration is not suitable
for electric heat. DO NOT try to install hydronic heater in a unit not
equipped for it. Verify connections: hot water to “in” and cold water
to “out”. 7/8” OD stubs are provided for plumbing connections. Bleed
the air ow system through the bleeder port or optional valve.
Fig. 16-1 Fig. 16-2

12 IO-123163 Effective 01-14-2016
Below are brief descriptions of the key components of the unit
and installation. This manual only provides general idea of the
components and recommended practices. The installer should use
best judgement to ensure safe installation and operation of the unit.
1. Room Thermostat- This is the device that controls that operation
of your heating and/or cooling unit. It senses the indoor temperature
and signals the equipment to start or stop maintaining the temperature
you have selected for your comfort. The room thermostat should be
in a central, draft free inside wall location for best operation. Do not
place any heat producing apparatus such as lights, radio, etc., near
the thermostat as this will cause erratic operation of the comfort
system. The thermostat can accumulate dust or lint which can affect
its accuracy. It should be cleaned annually.
2. Air Filter(s) - All central air moving comfort systems must include
air lter(s). These lters will be located either in the equipment or in
the return air duct system upstream of the equipment. The lter(s)
removes dust and debris from the air thus helping to keep your air-
conditioned space clean. More important, the lter keeps dust and
debris from collecting on the heat transfer surfaces thus maintaining
18. Operation and Maintenance
4. a) Do not store combustible materials
or use gasoline or other ammable liquids
or vapors in the vicinity of this appliance.
b) Do not operate the comfort equipment with panels
removed.
c) Have your contractor point out and identify the various
cut-off devices, switches, etc., that serve your comfort
equipment. There is a main switch that will cut off energy to
your heating system. Know where they are so that you may
cut off the ow of energy in the event of overheating.
!WARNING
optimum equipment efciency and performance. Inspect and clean
or replace lters every month. This routine maintenance procedure
will pay big dividends in reduced operating cost and reduced service
expense. Never operate comfort equipment without lter(s).
3. Fuses and/or Circuit Breakers- This comfort equipment should
be connected to the building electric service in accordance with
local and National Electric codes. This electrical connection will
include over-current protection in the form of circuit breakers. Have
your contractor identify the circuits and the location of over-current
protection so that you will be in a position to make inspections or
replacements in the event the equipment fails to operate.
5. Periodic Checkup and Service- This product is designed to provide
many years of dependable, trouble-free comfort when properly
maintained. Proper maintenance will consist of annual check-ups
and cleaning of the internal electrical and heat transfer components
by a qualied service technician. Failure to provide periodic checkup
and cleaning can result in excessive operating cost and/or equipment
malfunction.
6. Lubrication- Direct drive blower motors are equipped with
permanently lubricated bearings and do not require further lubrication.
7. Air lter replacement: An air lter can restrict the airow of air to the
fan coil if it is not cleaned or replaced periodically. When replacing
the air lter, always replace with the same type and size as originally
furnished with the unit.
Turn on power supply. Set thermostat fan switch to on. Set the
cooling indicator to maximum, heating to minimum. System switch
may be on heat or cool. Check slope gauge measurement against
appropriate air ow chart. Make damper, register and motor speed
adjustments to obtain required airow.
Set thermostat fan switch to auto, system to heat and thermostat
heating indicator to maximum heat. Blower should start and all heat
be energized.
Check air ow using temperature rise method.
17. Checking Air Flow/Temperature Rise Method
CFM
OUTPUT BTUH
TEMP RISE
=
•
()
..108
Note: BTUH output should be computed by 500 x Gallons Per
Minutes x System Temperature Change = BTUH OUTPUT. 1. Equipment Sizing Select an air handler with a heating output
that exceeds the space heating loss of the structure and that has a
cooling coil sized to match the outdoor condensing unit. Note: The
heating output of the air handler or hot water coil will not be greater
than the output of the selected hot water heater. Therefore, if the
water heater is undersized the heating BTUH of the air handler will
be LESS than its rated output.
2. Water Heater Selection
The following sizing information should only be used as a basic
guide to adequate water heater sizing because of variations in each
family’s domestic hot water requirements. For additional assistance
in water heater sizing contact a professional engineer. Proper water
heater sizing should consider both the gallon capacity AND the BTU
input of the water heater.
a. To determine water heater GALLON CAPACITY: A minimum
40-gallon high recovery and/or high efciency gas or oil-red
water heater is recommended. The following volume-sizing
guide is satisfactory in most areas of the country (Table 19-1).
19. Hydronic Related General Information
b. To determine water heater BTU INPUT (assumes a water
heater recovery efciency of 76%): For mild climates: BTU
INPUT=structure’s heat loss x 1.51. For colder climates: BTU
INPUT=structure’s heat loss x 1.58.
3. Pump Replacement
a. Disconnect electrical power to the unit before servicing.
b. Remove access door to reveal pump. Close supply valve (“A”)
and return valve (“B”). Open the air bleed valve to de-pressurize
the system and drain water.
c. Remove the metal pump housing by loosening the four screws
on the pump. DO NOT UN-SOLDER PUMP.
d. Replace the new pump housing assembly and reconnect
components to the pump. Before assembling, make sure that
the runner on the o-ring is in place on the pump housing.
e. Purge the system of the air as described earlier and re-connect
the electrical power.
Table 19-1.

IO-123163 Effective 01-14-2016 13
4. Little or no heat from water coil.
a. Purge the system.
b. The inlet connections may be reversed at the fan coil.
c. Water heater thermostat is not set at proper temp.
d. Water heater thermostat is not calibrated.
e. Dip tube in the water heater may not be installed correctly or
could be restricted.
f. Look for restrictions in heating system from water heater to
fan coil. Some water heaters are supplier with check valves,
remove any extra check valves except for the one supplied with
the fan coil.
g. The air handler is undersized for space being heated.
h. Water heater is undersized.
Note: All units installed in Massachusetts are required to be in
compliance with CMR 248 Massachusetts State Plumbing Code
and/or Massachusetts Fuel Gas Code.
These codes require the use of an optional pump timer to circulate
the hydronic loop independent of the thermostat.
1. Noisy Pump
System may not be totally purged of air. Purge the system again as
described in the start up section above.
2. T&P valve on water heater weeps This normally occurs when a
backow preventer has been installed in the cold water supply line
to the water heater. An expansion tank may be necessary to correct
this problem. Please contact a qualied plumbing professional for
assistance.
3. Hot water is circulating through the water coil during cooling
cycle The check valve may be stuck open and allowing hot water to
circulate through the coil.
20. Common Problems and Solutions
21. Final System Checkout
1. Make certain all cabinet openings are properly sealed and any
grommets moved during installation are moved into proper place.
2. With cooling system operating, check for condensate leakage.
3. Perform leak detection inspection of refrigerant circuit and
connecting piping.
4. Secure all cabinet doors

14 IO-123163 Effective 01-14-2016
Fig. 20-1 Wiring diagram for GFS/GFT models
HIGH VOLTAGE Disconnect ALL power sources prior to servicing. Failure might lead to safety hazard.
24V (COM) 24V (HOT)
TRANSFORMER
COM 120V
BK
WH
RBR
WH
WHR
BKBKWH BK BK BK
DIAGRAM # 101125
CURRENT 04/06/15
BK BK
WH WH
BK
RBR RBRBR GN/BK
ECM WIRING
SPEED TAPS
WH GN
UNIT
MODEL MED LO
GFS/T 18-24 GFS/T 30-36
HI
CFM AT .3 TAP SETTING
SPECIAL WIRING REQUIRED FOR
ALTERNATE SPEED TAP SETTINGS
COLOR CODE
W BK RD BK/W GN
- WHITE - BLACK - RED - BLACK/WHITE STRIPE - GREEN
WIRING CODE
FACTORY LOW VOLT
FIELD HIGH VOLT
FIELD LOW VOLT
FACTORY HIGH VOLT
Y B O GR BR GN/BK GN/RD
- YELLOW - BLUE - ORANGE - GRAY - BROWN -GREEN/BLACK STRIPE -GREEN/RED STRIPE
NOTE 2
NOTE 1
UNIT
MODEL
TABLE 1
ECM SPEED SETTING
SPEED
TAP
GN/BK
GFS/T 36 GFS/T 30 GFS/T 24
BK
GN
R
BR
BK
WH
WHR
BK
GN/BK
SPEED TAP
SEE TABLE 1
BR
WH
NOTE 4
NOTE 3
GFS/T 18
W
MED BLUE
HI YELLOW
MED BLUE
HI YELLOW
NOTE 5
650
1050
550
850 700
500
ORANGE & RED N/C

IO-123163 Effective 01-14-2016 15
Massachusetts Applicable Installation Diagram Massachusetts Applicable Installation Diagram

16 IO-123163 Effective 01-14-2016
373 Atascocita Rd.
Humble, TX 77396
Phone: [phone]
Toll Free: 800.423.9007
Fax: [phone]
www.airmark-ac.com
© Copyright 2015 AirMark. All Rights Reserved
Revised 10/29/2015. Subject to change without notice and without incurring obligation.