Geostar GAH022 User manual

INSTALLATION MANUAL
GEOTHERMAL HEAT PUMPS
AFFORDABLE RENEWABLE CLEAN
ASTON SERIES AIR HANDLER

3
Table of Contents
Model Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Initial Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Physical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
General Installation Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11
Hydronic Models. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12-13
Electrical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14-15
Wiring Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16-18
ECM Blower Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Blower Performance Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Dimensional Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21-24
Unit Startup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Replacement Procedures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Service Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Revision Guide. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
ASTON SERIESAIR HANDLER INSTALLATION MANUAL

4
Initial Inspection
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.
Model Nomenclature
ASTON SERIESAIR HANDLER INSTALLATION MANUAL
GAH 036 * 00 0 1 R
1-3 4-6 7 8-9 10 11 12
Model
GAH –G Series Air Handler
Unit Capacity
Refrigeration (DX) Models with Nominal CFM
022 MBTUH 800
026 MBTUH 925
030 MBTUH 980
036 MBTUH 1225
042 MBTUH 1425
048 MBTUH 1625
060 MBTUH 1760
Hydronic Models with Nominal CFM
026 MBTUH 925
036 MBTUH 1225
048 MBTUH 1625
060 MBTUH 1760
Vintage
* = Factory Use Only
Air Coil
R–Refrigerant
H - Hydronic
Motor
1–ECM 208-230/60/1
Disconnect
0–No Breaker Installed
(only on 5kW & 10kW Heaters)
1–Breaker Installed
(only on 15kW & 20kW Heaters)
Electric Heat
00 –None
05 –5kW (022 –036 only)
10 –10kW (030 –060 only)
15 –15kW (042 –060 only)
20 –20kW (060 only)
Rev.: 08 April 2013D
NOTE: To field convert the GAH042-060 to bottomflow air discharge, the NAHBC kit must be ordered.

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
General Installation Information
Physical Data
ASTON SERIESAIR HANDLER INSTALLATION MANUAL
GAH022 GAH026 GAH030 GAH036 GAH042 GAH048 GAH060
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
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]
4/28/14
GAH026 GAH036 GAH048 GAH060
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
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]
8/15/14
220 [99.79]
200 [90.71]
208/230 - 1ph
ECM variable speed
1/2 [373] 1 [746]
20 x 24 [508 x 635]
3/4 [19.05]
11 x 10 [279 x 254]
Air Handler Model Number (Hydronic)
Hydronic
Coil 3
7/8 [22.22]
13
7/8 [22.22]
6.94 [0.64]
3/8 [9.52]
Air Handler Model Number (Refrigerant)
Evaporator
Coil
5.83 [0.54]
3/8 [9.52]
23
12
5/8 [15.87] 7/8 [22.22]
3/8 [9.52]
Refrigerant R-410a
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]
Note: Water connection dimensions are O.D.

6
General Installation Information cont.
Moving and Storage
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.
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).
ASTON SERIESAIR HANDLER INSTALLATION MANUAL
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.
Air Handler Indoor Split Model
(Single) Indoor Split Model (Dual Capacity) Outdoor Split Model (Dual Capacity) Airflow(CFM) Electric Heat (kW)
GAH022B***1R 103*022 - 800 5
GAH026B***1R - 103*026 104*026 925 5
GAH030B***1R 103*030 - - 980 5, 10
GAH036B***1R 103*036 - - 1225 5, 10
GAH036B***1R - 103*038 104*038 1225 5, 10
GAH042B***1R 103*042 - - 1425 10, 15
GAH048B***1R 103*048 - - 1625 10, 15
GAH048B***1R - 103*049 104*049 1625 10, 15
GAH060B***1R 103*060 - - 1760 10, 15, 20
GAH060B***1R - 103*064 104*064 1760 10, 15, 20
GAH060B***1R 103*070 - - 1760 10, 15, 20
GAH060B***1R - 103*072 104*072 1760 10, 15, 20
6/9/08

7
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.
General Installation Information cont.
Figure 1 - Factory configuration is top discharge and
horizontal left hand air discharge.
1.5"
3.0"
3/4" PVC
Coupling
Vent
3/4" PVC
1/8" per foot
ASTON SERIESAIR HANDLER INSTALLATION MANUAL

8
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.
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.
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.
Figure 2 - Bottomflow Air Handler
Figure 3 - Horizontal Right Hand Air Discharge
Rotate the coil support bracket to this position
General Installation Information cont.
ASTON SERIESAIR HANDLER INSTALLATION MANUAL

9
General Installation Information cont.
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 phos-
copper 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
ASTON SERIESAIR HANDLER INSTALLATION MANUAL

10
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.
TXV Superheat Adjustment Procedure (see figure 4)
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.
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
charge amounts used with the compression section.
TXV Superheat Adjustments
ASTON SERIESAIR HANDLER INSTALLATION MANUAL
Part
Number
GAH022,
GAH026,
GAH030
GAH036 GAH042 GAH048 GAH060
33P609-01 factory set
33P609-03 factory set
33P609-05 factory set open 2 turns
33P609-06 open 2 turns
Note: When installing these air handlers, follow the table
for initial txv setting.
Check sub-cooling and superheat to verify final setting.
Unit
Size Air Handler
20 feet 40 feet 60 feet Factory
Charge (oz.)
*Charge Amount
with GAH Air
Handler (oz.)
Suction Liquid Suction Liquid Suction Liquid
022 GAH022 5/8” OD 3/8” OD 5/8” OD 3/8” OD 3/4” OD 3/8” OD 56 78
030 GAH030 5/8” OD 3/8” OD 3/4” OD 3/8” OD 3/4” OD 3/8” OD 56 78
036 GAH036 5/8” OD 3/8” OD 3/4” OD 3/8” OD 3/4” OD 1/2” OD 56 86
042 GAH042 3/4” OD 3/8” OD 3/4” OD 3/8” OD 7/8” OD 1/2” OD 74 99
048 GAH048 3/4” OD 3/8” OD 7/8” OD 3/8” OD 7/8” OD 1/2” OD 90 115
060 GAH060 7/8” OD 1/2” OD 7/8” OD 1/2” OD 1-1/8” OD 1/2” OD 92 112
070 GAH060 7/8” OD 1/2” OD 7/8” OD 1/2” OD 1-1/8” OD 1/2” OD 108 132
026 GAH026 5/8” OD 3/8” OD 3/4” OD 3/8” OD 3/4” OD 1/2” OD 52 74
038 GAH036 3/4” OD 3/8” OD 3/4” OD 3/8” OD 3/4” OD 1/2” OD 56 86
049 GAH048 3/4” OD 3/8” OD 7/8” OD 3/8” OD 7/8” OD 1/2” OD 90 115
064 GAH060 7/8” OD 1/2” OD 7/8” OD 1/2” OD 1-1/8” OD 1/2” OD 92 112
072 GAH060 7/8” OD 1/2” OD 7/8” OD 1/2” OD 1-1/8” OD 1/2” OD 104 132
4/6/10
Refrigerant Line Sizing
NOTES: * The "ChargeAmount with GAH Air Handler" column is based on the charge amount for a GAHAir 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.

11
General Installation Information cont.
Figure 4:
Decrease Superheat: Open Valve
Increase Superheat: Close Valve
ASTON SERIESAIR HANDLER INSTALLATION MANUAL

12
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. Plug for coil drainage.
Dole valve for air purging
Typical Installation. See the Hydronic Application Guide for other applications
ASTON SERIESAIR HANDLER INSTALLATION MANUAL
LOAD PUMP
Source OUT
P/T PortsP/T Ports
Ball Valve
Dielectric
Unions
Dielectric
Unions
G Series
HYDRONIC UNIT
G Series
HYDRONIC AIR HANDLER
*NOTE: A 30 PSI pressure relief valve
(Part No: SRV30) should be used in
hydronic applications.
Ý
FPT
Expansion
Tank
Air
Vent
Pressure
Gauge
30 PSI
RELIEF VALVE
Air
Separator
TO
DSH FROM
DSH
Back Flow Preventer /
Pressure Relief Valve
Source IN
GEO
STORAGE
TANK
P/T Ports

13
Hydronic Models cont.
Flow gpm Pressure Drop (PSI)
40°F 50°F 60°F 100°F 110°F 120°F 130°F
3.0 0.5 0.5 0.5 0.4 0.4 0.4 0.4
4.5 0.9 0.9 0.9 0.8 0.8 0.8 0.8
6.0 1.4 1.4 1.4 1.2 1.2 1.2 1.2
9.0 2.8 2.6 2.5 2.4 2.4 2.4 2.3
12.0 4.6 4.4 4.2 4.0 4.0 4.0 3.9
15.0 7.0 6.8 6.6 6.0 6.0 5.9 5.8
Water Presure Drop - Hydronic Coil
Entering Water Temperature °F
EAT °F 100 110 120 130 140 150
65 44% 56% 69% 81% 94% 106%
70 37% 50% 63% 75% 87% 100%
Coil Capacity vs. Entering Water Temperature
ASTON SERIESAIR HANDLER INSTALLATION MANUAL

14
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 auxil-
iary 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 aux-
iliary heat breakers need to be rewired so that breakers in the aux-
iliary 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.
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).
Air Handler Control Section:
Power should be supplied to PB on air handlers with no electric
heat and 5kW or 10kW heaters.
Electric Heat Control Section:
Power should be supplied to the breakers on air handlers with
15kW and 20kW heaters.
ASTON SERIESAIR HANDLER INSTALLATION MANUAL

15
Low Voltage Point to Point Wiring
To Air
Handler From Thermostat To Compressor Section
CC C
RR R
GG
OO O
Y1 Y1 Y1
Y2 Y2 Y2
W2 W
LL
Air Handler transformer must be 75VA. 5/29/08
Electrical Data cont.
Model Electric Heat Capacity Supply
Circuit
Aux. Heat
Minimum
CFM Rated Voltage Voltage Min/
Max Blower Motor FLA Heater Ampacity Total Unit FLA Minimum Circuit
Ampacity Maximum Fuse/ HACR
KW BTUH
240v 240v 208v 240v 208v 240v 208v 240v 208v 240v
022 00 -
208-230/60/1 197/253
4.0 - - 4.0 4.0 5.0 5.0 10 10
4.8 16,382 single 740 4.0 17.3 20.0 21.3 24.0 26.6 30.0 30 30
026 0 0 - 4.0 - - 4.0 4.0 5.0 5.0 10 10
4.8 16,382 single 740 4.0 17.3 20.0 21.3 24.0 26.6 30.0 30 30
030 0 0 - 4.0 - - 4.0 4.0 5.0 5.0 10 10 4.8 16,382 single 740 4.0 17.3 20.0 21.3 24.0 26.6 30.0 30 30
9.6 32,765 single 900 4.0 34.7 40.0 38.7 44.0 48.4 55.0 50 60
036 0 0 - 4.0 - - 4.0 4.0 5.0 5.0 10 10 4.8 16,382 single 740 4.0 17.3 20.0 21.3 24.0 26.6 30.0 30 30
9.6 32,765 single 900 4.0 34.7 40.0 38.7 44.0 48.4 55.0 50 60
042
0 0 - 7.0 - - 7.0 7.0 8.8 8.8 15 15
9.6 32,765 single 900 7.0 34.7 40.0 41.7 47.0 52.1 58.8 60 60
14.4 49,147 single 1,275 7.0 52.0 60.0 59.0 67.0 73.8 83.8 80 90
14.4 49,147 L1/L2 7.0 34.7 40.0 41.7 47.0 52.1 58.8 60 60
L3/L4 - 17.3 20.0 17.3 20.0 21.6 25.0 25 25
048
0 0 - 7.0 - - 7.0 7.0 8.8 8.8 15 15
9.6 32,765 single 900 7.0 34.7 40.0 41.7 47.0 52.1 58.8 60 60
14.4 49,147 single 1,275 7.0 52.0 60.0 59.0 67.0 73.8 83.8 80 90
14.4 49,147 L1/L2 7.0 34.7 40.0 41.7 47.0 52.1 58.8 60 60
L3/L4 - 17.3 20.0 17.3 20.0 21.6 25.0 25 25
060
0 0 - 7.0 - - 7.0 7.0 8.8 8.8 15 15
9.6 32,765 single 900 7.0 34.7 40.0 41.7 47.0 52.1 58.8 60 60
14.4 49,147 single 1,275 7.0 52.0 60.0 59.0 67.0 73.8 83.8 80 90
14.4 49,147 L1/L2 7.0 34.7 40.0 41.7 47.0 52.1 58.8 60 60
L3/L4 - 17.3 20.0 17.3 20.0 21.6 25.0 25 25
19.2 65,530 single 1,700 7.0 69.3 80.0 76.3 87.0 95.4 108.8 100 110
19.2 65,530 L1/L2 7.0 34.7 40.0 41.7 47.0 52.1 58.8 60 60
L3/L4 - 34.7 40.0 34.7 40.0 43.4 50.0 50 50
7/11/08
Rated Voltage of 208/230/60/1
HACR circuit breaker in USA only
ASTON SERIESAIR HANDLER INSTALLATION MANUAL

16
Wiring Schematics
Air Handler Wiring Schematic - 208-230/60/1 97P787-02
Air Handler No Electric Heat
Thermostat
R
C
Y1
O
W
Y2
Transformer
GECM
Blower
Motor
Grn
On/Off
BK
RPM
C2
RPM grnd
2 3 4 51
Blk/Wh
Yel
24V
C1
EM / W2
ADJUST
DELAY
COOL
Y /Y2
R
Y1
O
W / W1
HEAT
L2L1
PB
Orange
Brown
P4
XFRM
SEC
C
11
12
16
8
1
7
6
13
9
10
15
3
5
4
2
14
R
Y1
Y2
On
SW1
1
2
3
4
5
6
7
8
9
10
O/B
G
W1
ODD
W2
C
R
LED
W1 W2
Black
Blue
Red NOTE 1
11
12
16
8
1
7
10
3
5
4
6
13
9
15
2
14
G
Grn/Yel(1)
Note 3
P3
13 Black (13)
Black (2)
Black (9)
Black (15)
Black (14)
Black (6)
Black (10)
Black (4)
Black (11)
Black (7)
Black (5)
Black (12)
Black (16)
Black (1)
Black (3)
Black (8)
208-230/60/1
Notes:
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.
4 – Use manufacturer’s part number 19P592-01
(jumper bar assembly) when single source power is
required.
5 – Low voltage wiring CLASS 2.
Light emitting diode - Green
208-230V Relay coil
Electric Heat Contactor
Polarized connector
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
Thermal Limit Switch
Field wire lug
Ground
HE -
PB -
SW1 -
Heater element
Power block
DIP package 10 position
Legend
N.O., N.C.
G
L1
ER1 to ER4 - Aux heat stage relays
123
P
EHC
EHC
Breaker
TS
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 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.
Dual Power Supply Connections
ASTON SERIESAIR HANDLER INSTALLATION MANUAL

17
Air Handler 10kW Electric Heat
Thermostat
R
C
Y1
O
W
Y2
Transformer
G
Grn
2 3 4 51
Blk/Wh
Yel
24V
208-230/60/1
L2L1
PB
Orange
Brown
TDR
Wht(10) Blu(11)
Grn(9)
Wht(8)
Grn(9)
P4
XFRM
SEC
C
R
Y1
Y2
On
SW1
1
2
3
4
5
6
7
8
9
10
O/B
G
W1
ODD
W2
C
R
LED
W1 W2
Black
Blue
Red NOTE 1
Gry(4)
Yel(5)
G
Grn/Yel(1)
Electric Heat
HE1 TS1
Gry(12)
Yel(16)
Note 3
P3
ECM
Blower
Motor
On/Off
BK
RPM
C2
RPM grnd
C1
EM / W2
ADJUST
DELAY
COOL
Y /Y2
R
Y1
O
W / W1
HEAT
11
12
16
8
1
7
10
3
5
4
6
13
9
15
2
14
11
12
16
8
1
7
6
13
9
10
15
3
5
4
2
14
Black (13)
Black (2)
Black (9)
Black (15)
Black (14)
Black (6)
Black (10)
Black (4)
Black (11)
Black (7)
Black (5)
Black (12)
Black (16)
Black (1)
Black (3)
Black (8)
Gry(13)
Gry(6)
Yel(15)
Yel(7)
P2
P1
C1234
Gray
ER4
NO
ER3
NO
ER2
NO
ER1
NO
C
1
2
3
4
HE3 TS3
NOTE 2
Grn(9)
Air Handler 5kW Electric Heat
Thermostat
R
C
Y1
O
W
Y2
Transformer
G
Grn
23451
Blk/Wh
Yel
24V
208-230/60/1
L2L1
PB
Orange
Brown
Grn(9)
Wht(28)
P4
XFRM
SEC
C
R
Y1
Y2
On
SW1
1
2
3
4
5
6
7
8
9
10
O/B
G
W1
ODD
W2
C
R
LED
W1 W2
Black
Blue
Red NOTE 1
Gry(4)
G
Grn/Yel(1)
Electric Heat
Note 3
P3
ECM
Blower
Motor
On/Off
BK
RPM
C2
RPM grnd
C1
EM / W2
ADJUST
DELAY
COOL
Y /Y2
R
Y1
O
W / W1
HEAT
11
12
16
8
1
7
10
3
5
4
6
13
9
15
2
14
11
12
16
8
1
7
6
13
9
10
15
3
5
4
2
14
Black (13)
Black (2)
Black (9)
Black (15)
Black (14)
Black (6)
Black (10)
Black (4)
Black (11)
Black (7)
Black (5)
Black (12)
Black (16)
Black (1)
Black (3)
Black (8)
Gry(6)
Gry(13)
Gry(12)
P2
P1
C1234
Gray
ER4
NO
ER3
NO
ER2
NO
ER1
NO
C
1
2
3
4
HE1 TS1
NOTE 2
Wiring Schematics cont.
ASTON SERIESAIR HANDLER INSTALLATION MANUAL

18
Wiring Schematics cont.
Air Handler w/ 20kW Electric Heat
Thermostat
R
C
Y1
O
W
Y2
Transformer
G
Grn
2 3 4 51
Blk/Wh
Yel
24V
208-230/60/1
G
L2L1
PB
Orange
Brown
TDR
Grn(9)
L1L2
BRK2
L1L2
BRK1
Wht(8)
Grn(9)
P4
XFRM
SEC
C
R
Y1
Y2
On
SW1
1
2
3
4
5
6
7
8
9
10
O/B
G
W1
ODD
W2
C
R
LED
W1 W2
G
Circuit 2 208-230/60/1
Circuit 1
Black
Blue
Red NOTE 1
Red (2)
Black(3)
Grn/Yel(1)
Electric Heat
Note 3
P3
ECM
Blower
Motor
On/Off
BK
RPM
C2
RPM grnd
C1
EM / W2
ADJUST
DELAY
COOL
Y /Y2
R
Y1
O
W / W1
HEAT
11
12
16
8
1
7
10
3
5
4
6
13
9
15
2
14
11
12
16
8
1
7
6
13
9
10
15
3
5
4
2
14
Note 4
Black (13)
Black (2)
Black (9)
Black (15)
Black (14)
Black (6)
Black (10)
Black (4)
Black (11)
Black (7)
Black (5)
Black (12)
Black (16)
Black (1)
Black (3)
Black (8)
EHC
Yel(17)
Blk(15)
Gry(13)
HE3 TS3
HE2 TS2
HE1 TS1
Gry(12)
Blk(14)
Yel(16)
EHC
Blu
Blu
Blu(11)
Wht(10)
Gry(24)
Blk(25)
Yel(26)
Blk(21)
Gry(20)
Yel(22)
P2
Gray
ER4
NO
NOTE 2
ER3
NO
ER2
NO
ER1
NO
C
1
2
3
4C1234
P1
PNK(19)
Pnk(23)
Pnk(27) HE4 TS4
Pnk(18)
Air Handler w/ 15kW Electric Heat
Thermostat
R
C
Y1
O
W
Y2
Transformer
G
Grn
2 3 4 51
Blk/Wh
Yel
24V
208-230/60/1
G
L2L1
PB
Orange
Brown
TDR
Grn(9)
L1L2
BRK2
L1L2
BRK1
Wht(8)
Grn(9)
P4
XFRM
SEC
C
R
Y1
Y2
On
SW1
1
2
3
4
5
6
7
8
9
10
O/B
G
W1
ODD
W2
C
R
LED
W1 W2
G
Circuit 2 208-230/60/1
Circuit 1
Black
Blue
Red NOTE 1
Red (2)
Black(3)
Grn/Yel(1)
Electric Heat
Note 3
P3
ECM
Blower
Motor
On/Off
BK
RPM
C2
RPM grnd
C1
EM / W2
ADJUST
DELAY
COOL
Y /Y2
R
Y1
O
W / W1
HEAT
11
12
16
8
1
7
10
3
5
4
6
13
9
15
2
14
11
12
16
8
1
7
6
13
9
10
15
3
5
4
2
14
Note 4
Black (13)
Black (2)
Black (9)
Black (15)
Black (14)
Black (6)
Black (10)
Black (4)
Black (11)
Black (7)
Black (5)
Black (12)
Black (16)
Black (1)
Black (3)
Black (8)
EHC
Yel(17)
Blk(18)
Gry(13)
HE3 TS3
HE2 TS2
HE1 TS1
Gry(12)
Blk(14)
Yel(16)
EHC
Blu
Blu
Blu(11)
Wht(10)
Gry(24)
Blk(25)
Yel(26)
Blk(21)
Gry(20)
Yel(22)
P2
Gray
ER4
NO
NOTE 2
ER3
NO
ER2
NO
ER1
NO
C
1
2
3
4C1234
P1
ASTON SERIESAIR HANDLER INSTALLATION MANUAL

19
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.
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.
ASTON SERIESAIR HANDLER INSTALLATION MANUAL

20
DIPS Switch Description
Air Handler DIP
Switches
1Used to set normal CFM
2
3Not used
4
5Used to set aux./emergency heat CFM
6
7Not used
8
9 Used to set dehumidification CFM
10 Not used
Blower Performance
Blower Performance Variable Speed ECM
Model Max ESP
(wg)
Blower
Motor
(hp)
HP CFM Setting Normal Mode Htg & Clg Dehumidification Mode Clg Aux CFM Setting Aux
Emerg
Mode
S1 S2 Stg 2 Stg 1 Blower S9 Stg 2 Stg 1 Blower S5 S6
022
0.50 1/2 On On 900 700 450 Off 775 600 450 On On 1000
0.50 1/2 Off On 800 625 400 Off 680 530 400 Off On 800
0.50 1/2 On Off 700 540 375 Off 600 450 375 On Off 775
0.50 1/2 Off Off 640 480 350 Off Off 740
026
0.50 1/2 On On 1050 800 525 Off 850 700 525 On On 1150
0.50 1/2 Off On 925 725 475 Off 760 620 475 Off On 950
0.50 1/2 On Off 800 625 425 Off 670 540 425 On Off 925
0.50 1/2 Off Off 740 575 400 Off Off 825
030
0.50 1/2 On On 1150 950 600 Off 975 775 600 On On 1250
0.50 1/2 Off On 980 780 500 Off 825 640 500 Off On 1000
0.50 1/2 On Off 900 700 440 Off 750 580 440 On Off 975
0.50 1/2 Off Off 800 630 425 Off Off 900
036
0.50 1/2 On On 1300 1025 760 Off 1105 871 760 On On 1300
0.50 1/2 Off On 1225 950 685 Off 1041 808 685 Off On 1250
0.50 1/2 On Off 1150 850 620 Off 940 690 620 On Off 1225
0.50 1/2 Off Off 1075 800 550 Off Off 1200
042
0.75 1 On On 1500 1100 750 Off 1250 900 750 On On 1550
0.75 1 Off On 1425 1010 650 Off 1180 840 650 Off On 1450
0.75 1 On Off 1300 975 635 Off 1080 800 635 On Off 1400
0.75 1 Off Off 1150 850 625 Off Off 1275
048
0.75 1 On On 1700 1300 975 Off 1400 1080 975 On On 1700
0.75 1 Off On 1625 1240 875 Off 1350 1025 875 Off On 1550
0.75 1 On Off 1450 1100 750 Off 1200 900 750 On Off 1525
0.75 1 Off Off 1300 1000 675 Off Off 1400
060
0.75 1 On On 1850 1750 1175 Off 1540 1450 1175 On On 1850
0.75 1 Off On 1760 1625 1050 Off 1460 1350 1050 Off On 1760
0.75 1 On Off 1720 1575 1015 Off 1425 1300 1015 On Off 1725
0.75 1 Off Off 1680 1525 975 1428 Off Off 1700
2/3/10
Factory CFM settings are in boldface
CFM is controlled within 5% up to maximum ESP
Maximum ESP includes allowance for wet coil and standard filter
DIP switch 9 must be 'OFF' to select dehumidification mode
ASTON SERIESAIR HANDLER INSTALLATION MANUAL