When the equipment is received, all items should be carefully
checked against the bill of lading to be sure all crates and cartons
have been received. Examine units for shipping damage, removing
the units from the packaging if necessary. Units in question
should also be internally inspected. If any damage is noted, the
carrier should make the proper notation on the delivery receipt,
acknowledging the damage.
4
Physical Data
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
Air Handler Model Number (Refrigerant)
Evaporator
Coil
RefrigerantR-410a
Nominal cooling capacity - tons [kW]1.8 [6.44] 2.1 [7.59] 2.5 [8.79] 3 [10.55] 3.5 [12.30] 4 [14.06]5 [17.58]
Condensate drain connection - (O.D.) in. [mm]
Blower Wheel Size (Dia x W), in. [mm]
Blower motor type/speeds
Blower motor output - hp [W]
Filter Standard - 1" [51mm] MERV3 disposable, in. [mm]
Electrical characteristics (60hz)
Shipping weight - lbs. [kg]
Operating weight - lbs. [kg]
Air Handler Model Number (Hydronic)
Hydronic
Coil
Nominal cooling capacity - tons [kW]2.1 [7.59] 3 [10.55] 4 [14.06]5 [17.58]
Condensate drain connection - (O.D) in. [mm]
Blower Wheel Size (Dia x W), in. [mm]
Blower motor type/speeds
Blower motor output - hp [W]
Filter Standard - 1" [51mm] MERV3 disposable, in. [mm]
Electrical characteristics (60hz)
Shipping weight - lbs. [kg]
Operating weight - lbs. [kg]
Note: Water connection dimensions are O.D.
Air Coil Total Face Area, ft2 [m2]
Tube outside diameter - in. [mm]
Number of rows
Fins per inch
Suction line connection - in. [mm] sweat
Liquid line connection - in. [mm] sweat
Air Coil Total Face Area, ft2 [m2]
Tube outside diameter - in. [mm]
Number of rows
Fins per inch
Water In connection - in. [mm] sweat
Water Out connection - in. [mm] sweat
GAH022 GAH026 GAH030 GAH036 GAH042 GAH048 GAH060
5.83 [0.54]
3/8 [9.52]
23
12
5/8 [15.87]7/8 [22.22]
3/8 [9.52]
3/4 [19.05]
11 x 10 [279 x 254]
ECM variable speed
1/2 [373]1 [746]
20 x 24 [508 x 635]
208/230 - 1ph
215 [97.52]220 [99.79]
195 [88.45]200 [90.71]
GAH026 GAH036 GAH048 GAH060
6.94 [0.64]
3/8 [9.52]
3
13
7/8 [22.22]
7/8 [22.22]
3/4 [19.05]
11 x 10 [279 x 254]
ECM variable speed
1/2 [373]1 [746]
20 x 24 [508 x 635]
208/230 - 1ph
220 [99.79]
200 [90.71]
8/15/14
4/28/14
General Installation Information
Safety Considerations
Warning: Before performing service or maintenance
operations on a system, turn off main power switches to the
equipment. Electrical shock could cause personal injury.
Installing and servicing heating and air conditioning equipment can
be hazardous due to system pressure and electrical components.
Only trained and qualified service personnel should install, repair
or service heating and air conditioning equipment. Untrained
personnel can perform the basic maintenance functions of cleaning
coils and cleaning and replacing filters. All other operations should
be performed by trained service personnel. When working on
heating and air conditioning equipment, observe precautions in
the literature, tags and labels attached to the unit and other safety
precautions that may apply.
Follow all safety codes. Wear safety glasses and work gloves.
Use a quenching cloth for brazing operations and have a fire
extinguisher available.
Note: Local codes and regulations take precedent over any
recommendations by the manufacturer. In addition to conforming to
manufacturer’s and local municipal building codes, the equipment
should also be installed in accordance with the National Electric
Code and National Fire Protection Agency recommendations.
5
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
General Installation Information cont.
Air Handler Sizing Selection
The Aston Series Air Handlers are designed for R410a refrigerant and should be matched with Aston indoor and outdoor series
compressor section according to the table below.
If the equipment is not needed for immediate installation it should
be left in its shipping carton and stored in a clean, dry area. Units
must only be stored or moved in the normal “up” orientation.
Unit Location
Locate the unit in an indoor area that allows for easy removal of
the filter and access panels (the air handler units are not approved
for outdoor installation). Location should have enough space
for service personnel to perform maintenance or repair. Provide
sufficient room to make refrigerant, electrical and duct connections.
If the unit is located in a confined space, such as a closet,
provisions must be made for return air to freely enter the space
by means of a louvered door, etc. The air handler section may be
installed on any level surface strong enough to support its weight.
When installed in a closet or on a stand, it should be mounted
on vibration absorbing material slightly larger than the base to
minimize vibration transmission to the building structure.
When installed in an attic or above a drop ceiling, the installation
must conform to all local codes. If the unit is suspended and
installed in the horizontal position, the entire length of the unit
should be supported. If the application requires the air handler to
be installed on the attic floor then the unit should be set in a full
size secondary drain pan. In this case the secondary drain pan
should be set on top of a vibration absorbing mesh. The secondary
drain pan is usually placed on a plywood base. A secondary drain
pan should be used when equipment is installed over a finished
living area to provide protection from water damage in case of
plugging of the air handler primary drain line. The secondary drain
line should terminate somewhere that is easily visible by the
homeowner. Be certain to show the homeowner the termination
location of the secondary drain line and to explain its purpose.
Indoor Split Model
(Dual Capacity)
Outdoor Split Model
(Dual Capacity)
Airfl ow(CFM)Electric Heat (kW)
Duct System
The duct system should be sized to handle the design airflow
quietly and efficiently. To maximize sound attenuation of the unit
blower, the supply and return plenums should include an internal
duct liner of fiberglass or constructed of ductboard for the first
few feet. On systems employing a metal duct system, canvas
connectors should be used between the unit and the ductwork. If
air noise or excessive airflow is a problem, the blower speed can
be changed. Application of the unit to un-insulated metal ductwork
in an unconditioned space will cause poor unit performance and
allow condensation to form on the duct and possibly cause damage
to the structure.
If the unit is connected to existing ductwork, check the duct
system to ensure that it has the capacity to accommodate the air
required for the unit application. If the duct is too small, as in the
replacement of heating only systems, larger ductwork should be
installed. All existing ductwork should be checked for leaks and
repaired as necessary.
Condensate Drain
To facilitate condensate removal, the air handler should be pitched
1/4” towards the drain in both directions. The drain line contains
cold water and should be insulated in unconditioned spaces to
avoid drain line condensation from dripping on ceiling, etc. The
drain pan has a primary and auxiliary drain connection. The
21S521A03 condensate hose assembly kit is provided to connect
the drain pan's primary stainless steel tube to the PVC coupling
The air handler drain connections must be connected to a drain line
and pitched away from the unit a minimum of 1/8” per foot to allow
the condensate to flow away from the air handler. A trap must be installed in the drain line below the bottom of the drain pan to
ensure free condensate flow (units are not internally trapped).
6/9/08
6
General Installation Information cont.
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
The primary condensate drain must be terminated to an open drain
or sump. Do not connect the condensate drain to a closed waste
system. An open vertical air vent should be installed to overcome
line length, friction and static pressure. It is recommended that
the auxiliary drain be connected to a drain line for all units. The
auxiliary drain should be run to an area where the homeowner
will notice it draining. The drain line should not be smaller than
the drain connection at the condensate pan. If the air handler is
located in an unconditioned space, water in the trap may freeze. It
is recommended that the trap material be of a type that will allow
for expansion of water when it freezes. Drain lines must be in
conformance with local codes.
Air Handler Configuration
The air handler is factory configured for upflow and horizontal
left hand air discharge installation (Figure 1). For bottomflow or
horizontal right hand discharge, certain field modifications
are required.
Warning: Do not lift or reposition the ‘A’ coil by grasping the
copper tube header or distributor. This could cause a tubing
fracture resulting in a refrigerant leak.
Vent
3/4" PVC
Coupling
3/4" PVC
1/8" per foot
3.0"
1.5"
Figure 1 - Factory configuration is top discharge and
horizontal left hand air discharge.
7
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
General Installation Information cont.
Bottomflow Application
To convert the air handler for bottomflow applications follow the
steps shown below:
1. Remove all access panels. Disconnect the blower
harnesses from the motor and loosen ground wire from
blower. Remove the blower by removing 2 screws from
the blower mounting bracket, and slide the blower
assembly out the front. Remove the stiffener bracket in
front of coil, 'A' coil/pan assembly and the horizontal
drain pan. This will lighten the cabinet and make it easier
to maneuver.
2. Rotate the cabinet 180° from the upright position so that
the discharge air opening is located at the bottom and
the return air opening is at the top.
3. Install the blower assembly into the blower discharge
opening at the bottom of the cabinet by sliding the
blower mounting bracket under the discharge support
bracket and secure in place with 2 screws. The blower
harness and motor ground wire should be reattached
before sliding the blower into place.
4. On the 042-060 install the NAHBC bottomflow
conversion kit per instructions in the kit. Failure to install
this kit will result in condensate blow-off from the 'A'
coil into the cabinet and ductwork.
5. Install the 'A' coil into the upper section of the cabinet
as pictured in Figure 2. Attach the stiffener bracket into
the two holes provided in the cabinet so that the bracket
is in front of the coil. The horizontal drain pan is not
needed and must be discarded. Plug the 2 drain hole
openings in the access panel with the plugs provided.
6. Replace the access panels.
7. Bottom air discharge units require the supply air opening
to be cut at least a 1/2” larger than the unit’s air outlet.
8. When installed on combustible flooring, protect the
edges of the floor opening with sheet metal over wrap or
other non-combustible material.
9. Bottom air discharge units should be sealed well to the
floor to prevent air leakage.
Figure 2 - Bottomflow Air Handler
Horizontal Right Air Discharge Application
To convert air handler for horizontal right air discharge applications
follow the steps shown below
1. Remove all access panels. Remove the stiffener bracket
in front of the coil, ‘A’ coil assembly and the horizontal
drain pan.
2. From the vertical upflow position, rotate the top of the
cabinet 90° to the right and set in place.
3. Remove the support bracket mounted to the top plate of
the ‘A’ coil. Rotate the ‘A’ coil support bracket 180° from
its original position and re-attach into existing holes in
the top plate of the coil. This must be done to prevent
the ‘A’ coil from falling into the drain pan (Figure 3).
4. Move the horizontal drain pan from the left side of the ‘A’
coil to the right hand side of the ‘A’ coil. Place the ‘A’ coil
and horizontal drain pan assembly into the cabinet
so that the support bracket is resting in the horizontal
drain pan as shown in Figure 3. Attach the stiffener
bracket into the two holes provided in the cabinet so that
the bracket is in front of the coil.
5. Remove the 2 drain plugs from the upper right of the
access panel and install them on the lower left of the
access panel. Replace the access panels.
6. If the unit is suspended, the entire length of the cabinet
should be supported.
Figure 3 - Horizontal Right Hand Air Discharge
Rotate the coil support bracket to this position
Important: When removing the coil, there is possible danger
of equipment damage and personal injury. Be careful when
removing the coil assembly from the unit.
8
General Installation Information cont.
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
Air Handler Installation
The air handler is attached to the shipping pallet with screws. Prior
to setting the unit in place remove the shipping screws located in
the front base right behind the air filter access panel. Also remove
the external shipping brackets at the rear of the cabinet.
An air filter must always be installed upstream of the air coil on the
return air side of the air handler. An air filter is provided with the
air handler. If there is limited access to the filter rack for normal
maintenance, it is suggested that a return air filter grille be installed.
In this instance the filter supplied with the air handler should be
removed. Be sure that the return duct is properly installed and free
of leaks to prevent dirt and debris from bypassing the filter and
plugging the air coil.
The cabinet should be sealed so that unconditioned warm air can
not enter the cabinet. Warm air will introduce moisture into the
cabinet which could result in water blow-off problems, especially
when installed in an unconditioned space. Make sure that the
liquid line, suction line and drain line entry points into the cabinet
are well sealed. Use the butyl tape supplied with the air handler to
seal around the copper lines entering the cabinet.
All wall penetrations should be sealed properly. The line set should
not come into direct contact with water pipes, floor joists, wall
studs, duct work, floors, walls and brick. The line set should not
be suspended from joists or studs with a rigid wire or strap which
comes into direct contact with the tubing. Wide hanger straps which
conform to the shape of the tubing are recommended. All line sets
should be insulated with a minimum of 3/8” closed cell insulation.
The line set insulation should be pliable, and should completely
surround the refrigerant line. As in all R-410a equipment, a
reversible liquid line filter drier is required to insure all moisture
is removed from the system. This drier is factory installed in the
series compressor section. This drier should be replaced whenever
“breaking into” the system for service. All exterior insulation should
be painted with UV resistant paint or covering to insure long
insulation life.
Connection to the Coil
Connect the refrigerant line set to the ‘A’ coil tubes. Nitrogen
should be bled through the system at 2 to 3 PSI to prevent
oxidation inside the refrigerant tubing. Use a low silver phoscopper braze alloy on all brazed connections. The air handler
TXV bulb is secured to the ‘A’ coil for shipping. The indoor and
outdoor compressor section is shipped with a factory charge and
the service valves are not to be opened until the line set and air
handler have been leak tested, purged and evacuated. A damp
towel or heat sink should be used on the service valves to prevent
damage caused by excessive heat.
Refer to the Refrigerant Line Sizing table to determine the proper
line set configuration for the system being installed. Line sets over
60 feet in length are not recommended. If the line set is kinked or
deformed and cannot be reformed, the bad section of pipe should
be replaced. A restricted line set will affect unit performance.
Line sets should be routed as directly as possible, avoiding any
unnecessary bends and turns.
Important Note:
The bulb will need to be attached to the suction line on the outside of
the cabinet once the refrigerant line connections have been made.
Leak Testing
The refrigeration line set must be pressurized and checked for
leaks before purging and charging the unit. To pressurize the line
set, attach refrigerant gauges to the service ports and add an inert
gas (nitrogen or dry carbon dioxide) until pressure reaches 60 to 90
PSIG. Never use oxygen or acetylene to pressure test the system.
Use an electronic leak detector or a good quality bubble solution to
detect leaks on all connections made in the field. Be sure to check
the service valve ports and stems for leaks. If a leak is found,
repair it and repeat the above steps. For safety reasons do not
pressurize the system above 150 PSIG. Purge pressure from the
line set slowly when the pressure test is complete. The system is
now ready for evacuation.
System Evacuation
Ensure that the line set and air coil are evacuated before opening
service valves. The line set and air coil must be evacuated to
250 microns with a good quality vacuum pump and use a vacuum
gauge to ensure that air and moisture are removed. With the
system shut off from the vacuum pump a sufficient system vacuum
is achieved when a 500 micron vacuum can be held for 30 minutes.
A fast rise to atmospheric pressure indicates a leak, while a slower
rise to around 1500 microns indicates moisture is still present in the
system and further evacuation is required.
Refrigeration
The GAH series air handlers are supplied with an expansion
device. Once the line set has been brazed into the air handler
the txv bulb must be attached to the suction line outside of the
cabinet and insulated with foam tape. Be careful not to crush the
txv bulb by over-tightening the clamp. The txv supplied has an
internal check valve so no external check valve is necessary. The
9
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
General Installation Information cont.
air handler TXV should be adjusted initially per TXV Superheat
Adjustments table. Check sub-cooling and superheat, refrigerant
charge and TXV may require further adjustment.
Charging the System
Refer to the unit Installation Manual for charging the system,
checking sub-cooling/superheat and unit operating parameters.
Refer to the Refrigerant Line Sizing table for initial refrigerant
TXV Superheat Adjustment Procedure (see figure 4)
charge amounts used with the compression section.
TXV’s may require adjustment for a specific application.
1. Remove the seal cap from the bottom of the valve.
2. Turn the adjustment screw counterclockwise to increase
superheat and clockwise to decrease superheat.
One complete 360° turn changes the superheat
approximately 3-4°F. You may need to allow as much as
30 minutes after the adjustment is made for the system
to stabilize.
3. Once the proper superheat setting has been achieved
replace and tighten the seal cap.
Warning – There are 8 total (360°) turns on the superheat
adjustment stem from wide open to fully closed. When adjusting
the superheat stem counterclockwise (superheat increase) and the
stop is reached, any further counterclockwise turning adjustment
will damage the valve.
NOTE: The air handler is factory supplied with a holding charge of
dry nitrogen.
TXV Superheat Adjustments
Part
Number
33P609-01factory set
33P609-03factory set
33P609-05factory set open 2 turns
33P609-06open 2 turns
GAH022,
GAH026,
GAH030
GAH036GAH042GAH048GAH060
Note: When installing these air handlers, follow the table
for initial txv setting.
Check sub-cooling and superheat to verify final setting.
NOTES: * The "Charge Amount with GAH Air Handler" column is based on the charge amount for a GAH Air Handler+Compressor Section/Split.
Additional charge will have to be added accordingly for line set length.
After Charge is added adjustments can be made to get appropriate subcooling and superheat.
Additional charge for R-410A is 0.50 oz. per ft. for 3/8 in. and 1.0 oz. per ft. for 1/2 in. tube.
Longer line sets will significantly reduce capacity and efficiency of the system as well as adversely effect the system reliability due to poor oil return.
Air
Handler
20 feet40 feet60 feet
SuctionLiquidSuctionLiquidSuctionLiquid
10
Factory
Charge (oz.)
*Charge Amount
with GAH Air
Handler (oz.)
4/6/10
General Installation Information cont.
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
Figure 4:
Decrease Superheat: Open Valve
Increase Superheat: Close Valve
11
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
Hydronic Models
The water heater and hydronic air handler must be located indoors
and not subject to freezing temperatures. The water heater must
be installed in accordance to local codes and its own installation
instructions. The piping between the water heater and air handler
should be kept to a minimum. Piping should be sized to allow for
water velocities of 2’-4’ per second. At average water velocities,
air bubbles should be carried along the piping to an air separator
where they can be discharged from the system. Water velocities
greater than 4’ per second could cause flow noise and should be
avoided. If water lines pass through an unconditioned space they
should be protected to prevent them from freezing. Valves should
be installed to allow system isolation. All closed loop hydronic
systems must be equipped with an expansion tank to allow room
for the heated liquid to expand. A system is considered closed
when a check valve or backflow prevention valve is installed in the
cold water pipe upstream of the water heater.
Once piping is complete all air must be purged from the water lines.
There is a dole valve at the top of the hydronic coil header that can
be opened to purge air from the coil. There is also a plug at the
bottom of the hydronic coil header for draining the coil.
Dole valve for air purging
Plug for coil drainage.
Typical Installation. See the Hydronic Application Guide for other applications
30 PSI
RELIEF VALVE
Back Flow Preventer /
Pressure Relief Valve
Dielectric
Unions
Dielectric
Unions
Pressure
Gauge
GEO
STORAGE
TANK
Ý
FPT
Vent
Expansion
Tank
Air
Air
Separator
LOAD PUMP
TO
DSH
P/T Ports
G Series
HYDRONIC AIR HANDLER
FROM
DSH
Source OUT
P/T PortsP/T Ports
*NOTE: A 30 PSI pressure relief valve
(Part No: SRV30) should be used in
hydronic applications.
Ball Valve
Source IN
G Series
HYDRONIC UNIT
12
Hydronic Models cont.
Water Presure Drop - Hydronic Coil
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
Flow gpm
3.00.50.50.50.40.40.40.4
4.50.90.90.90.80.80.80.8
6.01.41.41.41.21.21.21.2
9.02.82.62.52.42.42.42.3
12.04.64.44.24.04.04.03.9
15.07.06.86.66.06.05.95.8
40°F50°F60°F100°F110°F120°F130°F
Pressure Drop (PSI)
Coil Capacity vs. Entering Water Temperature
Entering Water Temperature °F
EAT °F100110120130140150
6544%56%69%81%94%106%
7037%50%63%75%87%100%
13
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
Electrical Data
All field wiring must comply with local and national fire, safety
and electrical codes. Be sure the available power is the same
voltage and phase as that shown on the unit serial plate. Refer
to the unit Electrical Data table for fuse and circuit breaker sizing.
The thermostat should be connected to the air handler and to the
compressor section. Line voltage power should be supplied to the
breakers on air handlers with 15kW and 20kW heater kits (see the
electric heat control section picture).
15kW and 20kW Wiring Instructions
If two separate circuits are used to supply power to the auxiliary
heat kit, the installer will need to verify that each leg of the auxiliary circuit breakers are wired from the power supply correctly in
order for the electric heat kit to operate properly. This can be done
by measuring the supply side voltage of the auxiliary heat circuit
breakers. Put a voltmenter on the L2 side of Circuit Breaker One
and on the L2 side of Circuit Breaker Two. The voltmeter should
read approximately 0 volts. If the meter reads high voltage, the auxiliary heat breakers need to be rewired so that breakers in the auxiliary heat kit match the wiring of the Disconnect Panel breakers.
Meaning, L1 and L2 from one breaker in the disconnect panel must
connect to L1 and L2 at one of the auxiliary heat circuit breakers
and L1 and L2 from the other breaker in the disconnect panel must
connect to L1 and L2 of the other auxiliary heat circuit breaker,
making sure that the L1 and L2 from each disconnect breaker
matches the L1 and L2 at each of the auxiliary heat breakers.
Air Handler Control Section:
Power should be supplied to PB on air handlers with no electric
heat and 5kW or 10kW heaters.
On air handlers with no electric heat installed, or with 5kW and
10kW heater kits the power should be supplied to L1 and L2 lugs
on PB (see air handler control section picture).
Electric Heat Control Section:
Power should be supplied to the breakers on air handlers with
15kW and 20kW heaters.
14
Electrical Data cont.
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
Model
022
026
030
036
042
048
060
Rated Voltage of 208/230/60/1
HACR circuit breaker in USA only
Air Handler Wiring Schematic - 208-230/60/1 97P787-02
Legend
Factory Low voltage wiring
Factory Line voltage wiring
Field low voltage wiring
Field line voltage wiring
Optional block
DC Voltage PCB traces
Internal junction
Quick connect terminal
TS
Thermal Limit Switch
Field wire lug
L1
Ground
N.O., N.C.
ER1 to ER4 - Aux heat stage relays
1 – To operate in 208V mode replace the blue transformer
wire connected to PB-L2 with red transformer wire.
2 – Jumper wires are Factory Installed, and are needed for
electric heat operation.
3 – Dip switches are used to select the air flow.
Notes:
4 – Use manufacturer’s part number 19P592-01
(jumper bar assembly) when single source power is
required.
5 – Low voltage wiring CLASS 2.
P
G
EHC
EHC
1 2 3
PB -
SW1 -
HE -
Light emitting diode - Green
208-230V Relay coil
Electric Heat Contactor
Polarized connector
Power block
DIP package 10 position
Heater element
Breaker
Dual Power Supply Connections
If two separate circuits are used to supply power to the
auxiliary heat kit, the Installer will need to verify that each leg of
the auxiliary heat circuit breakers are wired from the power
supply correctly in order for the electric heat kit to operate
properly. This can be done by measuring the supply side
voltage of the auxiliary heat circuit breakers. Put a voltmeter on
the L2 side of Circuit Breaker One and on the L2 side of Circuit
Breaker Two. The voltmeter should read approxi
If the meter reads high voltage, the auxiliary heat breakers
need to be rewired so that breakers in the auxiliary heat kit
match the wiring of the Disconnect Panel breakers. Meaning,
L1 and L2 from one breaker in the disconnect panel must
connect to L1 and L2 at one of the auxiliary heat circuit
breakers and L1 and L2 from the other breaker in the
disconnect panel must connect to L1 and L2 of the other
auxiliary heat circuit breaker, making sure that the L1 and L2
from each d
isconnect breaker matches the L1 and L2 at each
of the auxiliary heat breakers.
mately 0 v
olts.
Yel
Grn/Yel(1)
Thermostat
C
R
Y1
Y2
G
O
W
208-230/60/1
Transformer
24V
Blk/Wh
C
XFRM
SEC
R
P3
ODD
Y1
Y2
O/B
W1
W2
G
Black
Red
NOTE 1
Blue
Note 3
C
R
SW1
G
W1
PB
L2L1
P4
8
LED
1
2
3
4
5
6
7
8
9
10
On
W2
3
1
16
12
5
7
11
4
10
6
14
15
9
2
13
13
Black (16)
Black (12)
Black (11)
Black (10)
Black (14)
Black (15)
Black (13)
Air Handler No Electric Heat
Black (8)
Black (3)
Black (1)
Black (5)
Black (7)
Black (4)
Black (6)
Black (9)
Black (2)
Brown
Orange
16
12
11
10
14
15
13
8
3
1
5
7
4
6
9
2
Grn
2 3 4 51
RPM grnd
C2
C1
RPM
R
COOL
ADJUST
HEAT
DELAY
BK
Y1
Y /Y2
On/Off
O
W / W1
EM / W2
ECM
Blower
Motor
16
Wiring Schematics cont.
208-230/60/1
G
PB
L2L1
LED
16
12
1
2
3
11
4
5
10
6
7
8
14
9
10
15
13
W2
Grn(9)
Yel
Grn/Yel(1)
Thermostat
C
R
Y1
Y2
G
O
W
Transformer
24V
Blk/Wh
C
XFRM
SEC
R
ODD
O/B
Black
Red
NOTE 1
Blue
Note 3
P3
C
R
On
SW1
Y1
Y2
G
W1
W2
W1
Air Handler 5kW Electric Heat
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
Gry(12)
Gry(13)
Gry(6)
HE1
TS1
Gry(4)
Brown
Orange
Grn
P4
8
Black (8)
3
Black (3)
1
Black (1)
Black (16)
Black (12)
5
Black (5)
7
Black (7)
Black (11)
4
Black (4)
Black (10)
6
Black (6)
Black (14)
Black (15)
9
Black (9)
2
Black (2)
Black (13)
2 3 4 51
8
RPM grnd
3
C2
1
C1
16
RPM
12
R
5
COOL
7
ADJUST
11
HEAT
4
DELAY
10
BK
Y1
6
14
Y /Y2
15
On/Off
O
9
2
W / W1
EM / W2
13
ECM
Blower
Motor
Wht(28)
NOTE 2
P1
C
1
2
3
4
C1234
Grn(9)
ER1
Gray
NO
ER2
NO
ER3
NO
ER4
NO
P2
Electric Heat
Grn(9)
208-230/60/1
G
PB
L2L1
P4
Black (8)
8
3
LED
1
2
3
4
5
6
7
8
9
10
W2
Black (3)
1
Black (1)
16
Black (16)
12
Black (12)
5
Black (5)
7
Black (7)
11
Black (11)
4
Black (4)
10
Black (10)
6
Black (6)
14
Black (14)
15
Black (15)
9
Black (9)
2
Black (2)
Black (13)
13
Yel
Grn/Yel(1)
Thermostat
C
R
Y1
Y2
G
O
W
Transformer
24V
Blk/Wh
C
XFRM
SEC
R
ODD
O/B
Black
Red
NOTE 1
Blue
Note 3
P3
C
R
On
SW1
Y1
Y2
G
W1
W2
W1
Air Handler 10kW Electric Heat
Brown
Orange
Yel(7)
Gry(12)
Yel(16)
Gry(13)
Yel(15)
Gry(6)
HE1
HE3
Electric Heat
TS1
TS3
Gry(4)
Yel(5)
Grn
2 3 4 51
8
RPM grnd
3
C2
1
C1
16
RPM
12
R
5
COOL
7
ADJUST
11
HEAT
4
DELAY
10
BK
Y1
6
14
Y /Y2
15
On/Off
O
9
2
W / W1
EM / W2
13
ECM
Blower
Motor
Wht(8)
Grn(9)
NOTE 2
P1
C
1
2
3
4
C1234
TDR
Wht(10)
Blu(11)
Gray
ER1
NO
ER2
NO
ER3
NO
ER4
NO
P2
17
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
Wiring Schematics cont.
Grn(9)
PB
L2L1
P4
Black (8)
8
3
LED
1
2
3
4
5
6
7
8
9
10
W2
Black (3)
1
Black (1)
16
Black (16)
12
Black (12)
Black (5)
5
7
Black (7)
11
Black (11)
4
Black (4)
10
Black (10)
6
Black (6)
Black (14)
14
15
Black (15)
9
Black (9)
2
Black (2)
Black (13)
13
Yel
Grn/Yel(1)
Thermostat
C
R
Y1
Y2
G
O
W
Transformer
24V
Blk/Wh
C
XFRM
SEC
R
ODD
Black
Red
NOTE 1
Blue
Note 3
P3
C
R
On
SW1
Y1
Y2
G
O/B
W1
W2
W1
Air Handler w/ 15kW Electric Heat
Brown
Orange
14
8
3
1
16
12
5
7
11
4
10
6
15
9
2
13
Red (2)
Black(3)
Grn
2 3 4 51
RPM grnd
C2
C1
RPM
R
COOL
ADJUST
HEAT
DELAY
BK
Y1
Y /Y2
On/Off
O
W / W1
EM / W2
ECM
Blower
Motor
Wht(8)
Grn(9)
208-230/60/1
Circuit 2
G
P1
C
1
2
3
4
NOTE 2
L1L2
BRK2
Blk(25)
Yel(26)
C1234
Wht(10)
TDR
208-230/60/1
Gry(24)
ER1
Gray
ER2
ER3
ER4
Blu(11)
Circuit 1
BRK1
NO
NO
NO
NO
P2
L1L2
Gry(20)
Gry(12)
Blk(14)
Yel(16)
Blk(21)
Yel(22)
EHC
G
Blu
Blu
Note 4
EHC
HE1
TS1
HE2
TS2
HE3
TS3
Electric Heat
Gry(13)
Blk(18)
Yel(17)
Grn(9)
PB
L2L1
P4
Black (8)
8
3
LED
1
2
3
4
5
6
7
8
9
10
W2
Black (3)
1
Black (1)
16
Black (16)
12
Black (12)
Black (5)
5
7
Black (7)
11
Black (11)
4
Black (4)
10
Black (10)
6
Black (6)
Black (14)
14
15
Black (15)
9
Black (9)
2
Black (2)
Black (13)
13
Yel
Grn/Yel(1)
Thermostat
C
R
Y1
Y2
G
O
W
Transformer
24V
Blk/Wh
C
XFRM
SEC
R
ODD
Black
Red
NOTE 1
Blue
Note 3
P3
C
R
On
SW1
Y1
Y2
G
O/B
W1
W2
W1
Air Handler w/ 20kW Electric Heat
Brown
Orange
3
1
16
12
5
7
11
4
10
6
14
15
9
2
13
Red (2)
Black(3)
Grn
8
2 3 4 51
RPM grnd
C2
C1
RPM
R
COOL
ADJUST
HEAT
DELAY
BK
Y1
Y /Y2
On/Off
O
W / W1
EM / W2
ECM
Blower
Motor
Wht(8)
Grn(9)
208-230/60/1
Circuit 2
G
P1
C
1
2
3
4
NOTE 2
L1L2
BRK2
Blk(25)
Yel(26)
Pnk(27)
C1234
Wht(10)
TDR
208-230/60/1
Gry(24)
ER1
Gray
ER2
ER3
ER4
Blu(11)
Circuit 1
BRK1
NO
NO
NO
NO
P2
L1L2
Gry(20)
Pnk(23)
Gry(12)
Blk(14)
Yel(16)
Blk(21)
Yel(22)
EHC
Pnk(18)
G
Blu
Blu
Note 4
EHC
HE1
TS1
HE2
TS2
HE3
TS3
HE4
TS4
Electric Heat
Gry(13)
Blk(15)
Yel(17)
PNK(19)
18
ECM Blower Control
The ECM blower motor is controlled by an interface board installed
in the air handler and allows field selectable CFM settings. The
interface board receives inputs from the thermostat and converts
them to signals used by the ECM motor. There are four different
airflow settings that are field selectable via DIP switches (see
Blower Performance table).
Cooling/Heating settings
The cooling/heating CFM settings determine the normal cooling/
heating CFM when the unit is not in dehumidification mode or
auxiliary heat mode. DIP switches 1 and 2 ‘off’ is the lowest CFM
setting while with DIP switches 1 and 2 ‘on’ is the highest CFM
setting. To prevent air coil freeze up, the lowest CFM setting can
not be used when dehumidification mode is selected. DIP 9 must
be ‘on’ to enable normal airflow settings.
Dehumidification Mode settings
This setting provides for field selection of humidity control (via
setting DIP 9 ‘off’). The cooling airflow settings are determined by
the Cooling/Heating DIP switch settings above. Dehumidification
mode reduces the selected normal cooling CFM by 15%-20%
which increases the moisture removing capability of the heat pump.
To prevent air coil freeze up, the lowest CFM setting can not be
used when dehumidification mode is selected.
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
Dehumidification Mode (Continuous) – This mode is selected via
setting DIP 9 ‘off’ on the ECM interface board and will be engaged
whenever an ‘O’ input is present. In this mode any time the unit is
operating in cooling mode, it will run at a CFM level 15%-20% lower
than the selected normal cooling CFM.
NOTE: Do not select dehumidification mode if the lowest Cooling/
Heating airflow level is selected (DIPS 1 & 2 off).
Auxiliary Heat settings - DIP 5 & 6 on the ECM interface board are
used to select the desired CFM in auxiliary/emergency heat mode.
Whenever auxiliary or emergency electric heat is energized this air
flow setting will be used.
19
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
Blower Performance
Blower Performance Variable Speed ECM
Max
Model
022
026
030
036
042
048
060
Factory CFM settings are in boldface
CFM is controlled within 5% up to maximum ESP
Maximum ESP includes allowance for wet coil and standard fi lter
DIP switch 9 must be 'OFF' to select dehumidifi cation mode
Discharge flange is field installed and extends 1" (25.4 mm) from cabinet
24
Unit Start Up
• Check that supply voltage matches nameplate data.
• Fuses, breakers and wire size are correct.
• Confirm that the 15kW or 20kW auxiliary heat kit
is wired correctly (see "Electrical Data" section if
applicable).
• Low voltage wiring is complete.
• Piping is complete and water system is cleaned
and flushed.
• Air is purged from the closed loop system.
• Isolation valves are open, water control valves or pumps
are wired.
• Condensate line is open and correctly pitched.
• Transformer switched to 208v if applicable.
• DIP switches are set correctly.
• Blower rotates freely.
• Blower speed is correct.
• Air filter/cleaner is clean and in position.
• Service/access panels are in place.
• Return air temperature is between 50-80°F heating and
60-95° cooling.
• Check air coil cleanliness to insure optimum performance.
Clean as needed according to maintenance guidelines.
To obtain maximum performance the air coil should be
cleaned before startup. A 10 percent solution of
dishwasher detergent and water is recommended for
both sides of coil. A thorough water rinse should follow.
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
Maintenance Filters
Filters must be clean to obtain maximum performance. They
should be inspected monthly under normal operating conditions
and be replaced when necessary. Units should never be operated
without a filter. Always replace the filter with the same type as
originally furnished.
Condensate Drain
In areas where airborne bacteria produce slime in the drain pan, it
may be necessary to treat chemically to minimize the problem. The
condensate drain can pick up lint and dirt, especially with dirty filters.
Blower Motors
The ECM motor is equipped with sealed ball bearings and requires
no periodic lubrication.
Air Coil
The air coil must be cleaned to obtain maximum performance.
Check once a year under normal operating conditions and, if dirty,
brush or vacuum clean. Care must be taken not to damage the
aluminum fins while cleaning.
Caution: Fin edges are sharp.
25
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
Replacement Procedures
Obtaining Parts
When ordering service or replacement parts, refer to the model
number and serial number of the unit as stamped on the serial
plate attached to the unit. If replacement parts are required,
mention the date of installation of the unit and the date of failure,
along with an explanation of the malfunctions and a description of
the replacement parts required.
In Warranty Material Return
Material may not be returned except by permission of authorized
warranty personnel. Contact your local distributor for warranty
return authorization and assistance.
16-19, 26 Updated Wiring Schematics, Unit Start Up01 April 2015MA
5-7, 22-24 Updated Hydronic Data15 Aug 2014MA
4-6,19,20 Updated Drain Pan20 May 2014DS/MA
AllUpdated Dimensional Data for New Vertical Condensate Drain02 May 2014DS
AllUpdated Nomenclature For New ECM Motor20 Feb 2013DS
22Added Service Parts List20 Feb 2013DS
23Added Revision Guide20 Feb 2013DS