Dettson AHB080014 User manual

Specifications subject to change without notice. September 2019
X40158 Rev.D
These instructions must be read and understood completely before attempting installation.
SAFETY CONSIDERATIONS
Improper installation, adjustment, alteration, service,
maintenance, or usecan cause explosion, fire, electrical shock, or
other conditions which may cause death, personal injury, or
property damage. Consult a qualified installer, service agency, or
your distributor or branch for information or assistance. The
qualified installer or agency must use factory-authorized kits or
accessories when modifying this product. Refer to the individual
instructions packaged with the kits or accessories when installing.
Follow all safety codes. Wear safety glasses, protective clothing,
and work gloves. Use quenching cloth for brazing operations.
Have fire extinguisher available. Read these instructions
thoroughly and follow all warnings or cautions included inliterature
and attached to the unit. Consult local building codes, the current
editions of the National Electrical Code (NEC) NFPA 70.
In Canada refer to the current editions of the Canadian Electrical
Code CSA C22.1 Recognize safety information. This is the safety-
alert symbol . When you see this symbol on the unit and in
instructions or manuals,be alert to the potential for personal injury.
Understand these signal words; DANGER, WARNING, and
CAUTION. These words are used with the safety-alert symbol.
DANGER identifies the most serious hazards which will result in
severe personal injury or death. WARNING signifies hazards
which could result in personal injury or death. CAUTION is used
to identify unsafe practices which may result in minor personal
injury or product and property damage. NOTE is used to highlight
suggestions which will result in enhanced installation, reliability or
operation.
TABLE OF CONTENTS
General Information/Installation..............................2
Installation..............................................................2
Horizontal Installation.............................................3
Ductwork Connection .............................................3
Filter Installation.....................................................3
Electrical Connection..............................................4
Motor Speed and Airflow........................................5
Blower Performance...............................................5
Airflow Check.........................................................5
Wiring Diagram ......................................................5
Replacement Parts.................................................6
WARNING
ELECTRICAL SHOCK HAZARD
Failure to turn off electric power could result in personal
injury or death.
Before installing or servicing system, turn off main power
to the system. There may be more than one disconnect
switch, including accessory heater(s).
INSTALLATION INSTRUCTIONS
Air Handler (115 Volt)
AHB080014, AHB120017, AHB160022, AHB200024

INSTALLATION INSTRUCTIONS Air Handler : AHB
2Specifications subject to change without notice. X40158 Rev.D
Figure 1
Dimensions and Clearances –in (mm)
CLEARANCES
ALL Sides………………………………… 0”
From Supply Duct………………………. 0”
Recommended Service From Front….. 20” (508mm)
(Service for blower)
ALL DIMENSIONS in (mm)
GENERAL INFORMATION
WARNING
DEATH, PERSONAL INJURY, AND/OR PROPERTY DAMAGE
HAZARD
Failure to carefully read and follow this warning could result
in equipment malfunction, property damage, personal injury
and/or death.
The information contained in this manual is intended for use
by a qualified service technician familiar with safety
procedures and equipped with the proper tools and test
instruments.
Installation must conform with local building codes and with
the National Electrical Code NFPA70 current edition.
The blower is unique and utilizes a 115vac PSC blower motor. The
cabinet may be used for cooling or heat pump applications. The
cabinet can be installed in an upflow, downflow or horizontal position
(Figure 3, 4).
LOCATION
Select the best position which suits the installation site conditions. The
location should provide adequate structural support, space in the front
of the unit for service access, clearance for return air and supply duct
connections, space for refrigerant piping connections and condensate
drain line connections. THESE BLOWERS ARE NOT TO BE USED
WITH ELECTRIC HEAT.
If the unit is located in an area of high humidity, nuisance sweating of
casing may occur. On these installations a wrap of 2” (51mm)
fiberglass insulation with a vapor barrier should be used.
CAUTION
CUT HAZARD
Failure to follow this caution may result in personal injury.
Sheet metal parts may have sharp edges or burrs. Use care
and wear appropriate protective clothing and gloves when
handling parts.
INSTALLATION
The unit is ready to install in any position without modifications.
Refer to the coil instructions for information on drain pan
configurations etc. Make sure coil is set up properly for desired
position of blower cabinet.
Coil must be secured to blower cabinet with the three tabs that are
part of the blower cabinet base. Bend the tabs out from the bottom
so they fit over the coil cabinet.
Position coil cabinet in relation to the blower so they will be correct
for desired application.
For upflow and horizontal applications apply foam seal strip around
top of coil cabinet. For downflow application apply foam seal strip
around bottom of coil cabinet. Set blower on top of coil cabinet so
they are flush. Secure cabinets together using the three tabs on the
bottom of the cabinet. Bend the tab out from the bottom so it fits over
the coil cabinet. If no pilot holes are present, drill a hole as required
for a screw.
20 ½’’
(521)
24’’ (610) –AHB08 & AHB12
25’’ (635) –AHB16 & AHB20
12-7/16” (316) –AHB08
15-3/4” (400) –AHB12
19-1/4’’ (489) –AHB16
22-3/4’’ (578) –AH B20
14-3/16” (360) –AHB08
17-1/2” (445) –AHB12
21’’ (533) –AHB16
24-1/2’’ (622) –AHB20

INSTALLATION INSTRUCTIONS Air Handler : AHB
X40158 Rev.D Specifications subject to change without notice. 3
Figure 2
Attach Coil to Blower Cabinet
Figure 3
Upflow/Downflow Airflow Positions
NON-DUCTED RETURN AIR CLOSET
INSTALLATION
The cabinet can be installed in a closet with a false bottom to form a
return air plenum, or mounted on an open platform inside the closet.
Platform should be high enough to provide a free (open) area for
adequate return airflow into the bottom of the cabinet. The open area
can be on the front side or a combination of front and sides, providing
there is clearance on the sides between cabinet and closet. Refer to
ACCA Manual D for sizing and free area recommendations.
NOTE: Local codes may limit application of systems without a ducted
return to single story dwellings.
HORIZONTAL LEFT AND RIGHT
INSTALLATIONS
The cabinets can be installed in either downflow, horizontal left or
horizontal right applications. When a coil cabinet is applied, refer to
the coil installation manual for proper drain pan and airflow
requirements. They must have the drain pan repositioned for right
hand airflow. Refer to coil installation manual.
CAUTION
PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in property damage.
A field fabricated auxiliary drain pan, with a separate drain
is REQUIRED for all installations over a finished living
space or in any area that may be damaged by overflow from
a restricted main drain pan. In some localities, local codes
require an auxiliary drain pan for ANY horizontal
installation.
SUSPENDED CABINET INSTALLATION
1. The cabinet may be supported on a frame or shelf, or it may be
suspended.
2. Use metal strapping or threaded rod with angle iron supports
under the auxiliary drain pan to suspend cabinet. These supports
MUST run parallel with the length of the cabinet (Figure 5).
3. Ensure that there is adequate room to remove service and access
panels after installing supporting brackets.
4. Place field installed vibration isolators in auxiliary drain pan to
support cabinet.
DUCT CONNECTIONS
Supply Duct
Supply duct must be attached to the outside of flange on outlet end of
unit. Flexible connectors may be used if desired.
Return Duct
Return duct should be attached to bottom of unit using sheet metal
screws or other fasteners.
FILTER INSTALLATION
Filters must be field supplied. A remote filter grille or other means
must be provided. Refer to ACCA Manual D for remote filter sizing.
Panels
removed
for clarity only
Place seal
on top of
Coil Cabinet
around
perimeter
Bend Tabs (both sides
and back) on Bottom of
Blower Cabinet to Fit
over Coil Cabinet
Figure 4 Horizontal Airflow Positions

INSTALLATION INSTRUCTIONS Air Handler : AHB
4Specifications subject to change without notice. X40158 Rev.D
NOTE
If increased structural strength is needed in the horizontal position,
use two field supplied connecting plates in place of the tabs on the
bottom of the blower.
ELECTRICAL CONNECTIONS
WARNING
ELECTRICAL SHOCK or UNIT DAMAGE HAZARD
Failure to follow this warning could result in personal injury,
death, and/or property damage.
Turn OFF electric power at fuse box or service panel before
making any electrical connections and ensure a proper
ground connection is made before connecting line voltage.
All electrical work MUST conform with the requirements of local codes
and ordinances and the National Electrical Code NFPA 70 current
edition.
THE LOW VOLTAGE TRANSFORMER AND THE FAN RELAY
ARE STANDARD ON ALL MODELS AND ARE PREWIRED AT
THE FACTORY. LINE VOLTAGE CONNECTIONS ARE MADE TO
THE WIRE PIGTAILS IN THE UNIT.
OVERCURRENT PROTECTION
The power supply wiring to the unit MUST be provided with
overcurrent protection. Governing codes may require this to be fuses
ONLY or circuit breakers.
For blower cabinets AHB08, AHB12 and AHB16 a 15 AMP circuit
should be used. For AHB20 a 20 AMP circuit should be used.
LINE VOLTAGE CONNECTIONS
Line voltage wiring may be brought into the unit through the top right-
hand corner. A hole for a 1/2” or 3/4” (12.7mm or 19mm) conduit fitting
is provided.
Connect field wiring to the wire pigtails. All line voltage connections
must be made with copper wire.
Line Voltage Connection
1. Provide line voltage power supply (115V) from a separate circuit.
2. Connect (115V) Hot to Black wire and Neutral to White wire.
GROUNDING CONNECTION
Use a copper conductor(s) from the ground lug to a grounded
connection in the electric service panel or a properly installed
grounding rod.
Figure 5 Horizontal Installation
Field-Fabricated
Drain Pan
Supports MUST run parallel with blower cabinet
Refrigerant
Lines
Drain
Lines
Vibration
Isolators
See Note
Below
Volts Phase Hertz
No. of
Wires
Wire Size
Max. Ft.
Length
No. of
Wires
Wire Size
MB08 115 160 Single 1/3 5.0 6.3 15 212 NEC* 1 14
MB12
MB16
MB20 115 160 Single 3/4 11.0 13.8 15 212 NEC* 1 14
* Refer to NEC anc local codes
Single
Supply Wire 75ºC copper
Ground Wire
15
Recommended
115
Supply
circuit No.
H.P.
Maximum
Motor
Amps
MCA
Branch
Circuit
Ampacity
Maximum
Overcurrent
Protection
Device
1
60
14
Supply Circuit
2
12
NEC*
1
1/2
6.5
8.1
See Note
beside
AHB08
AHB12
AHB16
AHB20

INSTALLATION INSTRUCTIONS Air Handler : AHB
X40158 Rev.D Specifications subject to change without notice. 5
LOW VOLTAGE CONTROL CONNECTIONS
The 24 volt power supply is provided by an internally wired 115/24V
low voltage transformer which is standard on all models.
Field supplied low voltage wiring can enter the unit on the top left
hand corner.
Install the strain relief bushing (supplied with unit) in the selected
hole.
Connect low voltage field wiring to the Brown (24V Common) and
Red (24V Hot), and Grey (24V Fan) pigtails.
MB08
ESP
In wc
SPEED
VOLTS
0.20
0.30
0.40
0.50
0.60
0.70
0.80
Low
115v
1011
1015
1011
985
942
875
796
Med
115v
1241
1225
1202
1175
1135
1075
991
High
115v
1387
1380
1372
1350
1311
1225
1119
MB12
ESP
In wc
SPEED
VOLTS
0.20
0.30
0.40
0.50
0.60
0.70
0.80
Low
115v
1037
1050
1058
1055
1041
1025
996
Med
115v
1323
1340
1352
1355
1345
1320
1276
High
115v
1671
1685
1696
1685
1654
1600
1531
MB16
ESP
In wc
SPEED
VOLTS
0.20
0.30
0.40
0.50
0.60
0.70
0.80
Low
115v
1046
1055
1055
1046
1034
1015
981
Med
115v
1369
1380
1384
1384
1368
1340
1300
High
115v
1718
1735
1750
1750
1736
1690
1634
MB20
ESP
In wc
SPEED
VOLTS
0.20
0.30
0.40
0.50
0.60
0.70
0.80
Low
115v
1397
1380
1366
1348
1321
1288
1235
Med
115v
1796
1790
1777
1750
1705
1640
1554
High
115v
2396
2300
2255
2190
2106
1995
1873
* THE MAXIMUM EXTERNAL STATIC PRESSURE IS 0.8’’ W.C.,
WITHOUT COOLING COIL. DEDUCT STATIC PRESSURE OF
COIL FOR MAXIMUM STATIC PRESSURE.
AIR FLOW CHECK
For proper system operation, the air flow through the indoor coil
should be between 350 and 450 cfm (165 and 212 L/s) per ton of
cooling capacity. The air flow through the unit can be determined by
measuring the external static pressure to the unit and selecting the
motor speed tap that will most closely provide the required air flow.
1. Set up to measure external static pressure at the supply and
return duct connections.
2. Drill holes in the ducts for pressure taps, pitot tubes, or other
accurate pressure sensing devices.
3. Connect these taps to a level inclined manometer or draft gauge.
4. Ensure thecoil and filter are clean, and all the registers are open.
5. Determine the external static pressure with the blower operating.
6. Refer to the Air Flow Data tables, to find the speed tap that will
most closely provide the required air flow for the system.
7. Refer to Motor Speeds and Airflow in these instructions if the
speed tap is to be changed.
8. Recheck the external static pressure with the new speed tap, and
confirm speed tap selection.
CARE AND MAINTENANCE
The system should be regularly inspected by a qualified service
technician. Consult the servicing dealer for recommended frequency.
Between visits, the only consumer servicerecommended or required
is air filter maintenance and condensate drain operation.
Keep the low voltage wiring as short as possible inside the control
box.
Complete connections between indoor blower, outdoor section,
indoor thermostat according to instruction provided with the
Condenser Installation Instructions and refer to Wiring Diagram.
MOTOR SPEEDS AND AIRFLOW
The motor speed can be set to one of three speeds. To change the
blower speed unplugs the black wire connection at the blower motor
and move to desired speed tap.
AIR FILTER
Inspect air filters at least monthly and replace or clean as required.
Disposable type filters should be replaced. Reusable type filters may
be cleaned by soaking in mild detergent and rinsing with cold water.
The frequency of cleaning depends upon the hours of operation and
the local atmospheric conditions. Install filters with the arrows on the
side pointing in the direction of air flow. Clean filters keep unit
efficiency high.
LUBRICATION
The bearings of the blower motor are permanently lubricated.
CONDENSATE DRAINS
During the cooling season check the condensate drain lines to be
sure that condensate is flowing from the primary drain but not from
the secondary drain. If condensate ever flows from the secondary
drain, the unit should be promptly shut off and the condensate pan
and drains cleaned to insure a free flowing primary drain.
AHB WIRING DIAGRAM
AHB08
AHB12
AHB16
AHB20

INSTALLATION INSTRUCTIONS Air Handler : AHB
X40158 Rev.D Specifications subject to change without notice. 6
REPLACEMENT PARTS
ITEM
NO.
CURRENT
PART#
DESCRIPTION
MB080014C1 MB120017C1 MB160021C1 MB200024C1
B60077-13 1 - - -
B60077-14 - 1 - -
B60077-15 - - 1 -
B60077-16 - - - 1
B60017-01 1 - - -
B60017-02 - 1 - -
B60017-03 - - 1 1
3B60106 WIRE CHANNEL 1 1 1 1
4B60107 DECK BLOWER RAIL RIGHT/LEFT 2 2 2 2
B60093 1 - - -
B60094 - 1 - -
B60095 - - 1 -
B60096 - - - 1
B60101 2 - - -
B60102 - 2 - -
B60103 - - 2 -
B60104 - - - 2
B60097 1 - - -
B60098 - 1 - -
B60099 - - 1 -
B60100 - - - 1
B60076-01 1 - - -
B60076-02 - 1 - -
B60076-03 - - 1 -
B60076-04 - - - 1
B60089-02 1 1 - -
B60090-02 - - 1 1
B60087-01 1 - - -
B60087-02 - 1 - -
B60088-01 - - 1 -
B60088-02 - - - 1
9
LEFT SIDE WRAPPER
10
BACK WRAPPER
7
REAR BLOWER DECK
8
PANEL TOP ASS'Y
5
FRONT BLOWER DECK
6
SIDE BLOWER DECK
1
BLOWER DOOR ASS'Y
2
PLATE HEATER CLOSURE ASS'Y
ITEM
NO.
CURRENT
PART#
DESCRIPTION
MB080014C1 MB120017C1 MB160021C1 MB200024C1
B60089-01 1 1 - -
B60090-01 - - 1 1
B60105-01 1 - - -
B60105-02 - 1 - -
B60105-03 - - 1 -
B60036-04 - - - 1
13 B60108 BLOWER RAIL RIGHT/LEFT 1 1 1 1
B01888-01 1 1 1 -
B01888-02 - - - 1
B01890-02 MOTOR ASS'Y (WITH MOTOR MOUNTS) 1/3HP - 3Spd 1 - - -
B01890-04 1/2HP - 3Spd - 1 - -
B01890-06 1/2HP - 3Spd - - 1 -
B01890-08 3/4HP - 3Spd - - - 1
Z01I027 BLOWER HOUSING WITH WHEEL 100-7R 1 - - -
Z01I028 100-8R - 1 - -
Z01I029 100-9R - - 1 1
17 B01024 CAPACITOR SUPPORT 1 1 1 1
L01I003 CAPACITOR 370V 10 MF 1 1 1 -
L01I012 440V 20 MF - - - 1
B60109-01 BRACKET CTL MTG 1 - - -
B60109-02 - 1 - -
B60109-03 - - 1 1
20 L01H009 24VAC SPDT RELAY 1 1 1 1
21 L01F011 TRANSFORMER 120-24v, 40VA 1 1 1 1
18
19
14
MOTOR MOUNT ASS'Y (BAND AND LEGS)
15
16
11
RIGHT SIDE WRAPPER
12
BRACE, BOTTOM FRONT
DETTSON INDUSTRIES INC.
DETTSON.COM
AHB08
AHB12
AHB16
AHB21
AHB08
AHB12
AHB16
AHB21