Marvair GeoScholar Series User manual

WARNING
SAFETY REQUIREMENTS
• If the information in these instructions are not
followed exactly, a re may result causing property
damage, personal injury or loss of life.
• Read all instructions carefully prior to beginning the
installation. Do not begin installation if you do not
understand any of the instructions.
• Improper installation, adjustment, alteration, service
or maintenance can cause property damage,
personal injury or loss of life.
• Installation and service must be performed by a
qualied installer or service agency in accordance
with these instructions and in compliance with
all codes and requirements of authorities having
jurisdiction.
• Follow all safety codes.
MODEL NO.: ______________________ SERIAL NO.: _________________
DATE OF START-UP.:_______________
INSTALLATION AND
START-UP
GeoScholar
Heat Pump
(CSI 15740)
MODELS VWIA, VWISA and VWCA, VWCSA
2, 2.5, 3, 3.5, 4 & 5 Tons
Part # 01516
GeoScholar IS Manual 03/2019
Rev. 2
P.O. Box 400 • Cordele, GA 31010
156 Seedling Drive • Cordele, GA 31015
[phone] • Fax: [phone]
Email: [email protected]
Internet: www.marvair.com

GeoScholar (I&S) 03/2019 15700 - 2 HVAC Equipment
How To Use This Manual
This manual is intended to be a guide to the Marvair®GeoScholar line of vertical packaged heat
pumps. It contains installation, troubleshooting, maintenance, warranty, and application information. The
information contained in this manual is to be used by the installer as a guide only. This manual does not
supersede or circumvent any applicable national or local codes.
If you are installing the GeoScholar heat pump, rst read the entire manual and Appendices for any
of the options and accessories before beginning the installation. The Appendices describe the installation
of the base stand, the plenum, trim strips, wall brackets, outdoor louvers and the sound reduction panel.
If a malfunction occurs, follow this troubleshooting sequence:
1. Make sure you understand how the GeoScholar unit works.
2. Identify and correct installation errors.
3. If you are still unable to correct the problem, contact the Factory at 1-800-841-7854 for additional
assistance.
Please read the following “Important Safety Precautions” before beginning any work. Failure
to follow these rules may result in death, serious bodily harm, property damage and damage to
the equipment. Denitions identifying hazard labels are shown below.
Failure to comply will result in death or severe personal injury and/or
property damage.
Failure to comply could result in death or severe personal injury and/or
property damage.
Failure to comply could result in minor personal injury and/or property
damage.
Important Safety Precautions
1. USE CARE when LIFTING or TRANSPORTING equipment.
2. TRANSPORT the UNIT UPRIGHT. Laying it down on its side may cause oil to leave the compres-
sor, resulting in DAMAGE upon START-UP.
3. TURN ELECTRICAL POWER OFF AT THE breaker or fuse box BEFORE installing or working on
the equipment. LINE VOLTAGES ARE HAZARDOUS or LETHAL.
4. OBSERVE and COMPLY with ALL applicable PLUMBING, ELECTRICAL, and BUILDING CODES
& ordinances.
5. SERVICE may be performed ONLY by QUALIFIED and EXPERIENCED PERSONS.
* Wear safety goggles when servicing the refrigeration circuit
* Beware of hot surfaces on refrigerant circuit components
* Beware of sharp edges on sheet metal components
* Use care when reclaiming or adding refrigerant
6. Use COMMON SENSE - BE SAFETY CONSCIOUS
Specications subject to change without notice.
© Marvair®, Division of AIRXCEL®, Inc.
!IMPORTANT
!WARNING
!CAUTION
!DANGER
!WARNING

GeoScholar (I&S) 03/2019 15700 - 3 HVAC Equipment
SECTION 15700
HEATING, VENTILATING AND AIR CONDITIONING EQUIPMENT
INSTALLATION AND START-UP INSTRUCTIONS
FOR GEOSCHOLAR HEAT PUMP (15740)
TABLE OF CONTENTS
Article Description Page
1.01 Tools/Field Furnished Supplies ......................................................4
1.02 Inspection/Unpacking/Handling......................................................4
1.03 Standard Controls ..........................................................................7
1.04 Controllers......................................................................................8
1.05 Options.........................................................................................10
1.06 Location Preparation.................................................................... 11
1.07 Power and Control Wiring (Rough-In).......................................... 11
1.08 Condensate Drain Line (Rough-In) ..............................................16
1.09 Wet Heat (Rough-In) ....................................................................16
1.10 Preparation of the GeoScholar Units ...........................................16
1.11 Installation Through the Outside Wall ..........................................19
1.12 Electric, Condensate, Water and Wet Heat Hook-ups .................20
1.13 Ventilation System Calibration .....................................................29
1.14 Control Adjustments.....................................................................31
1.15 Remote Thermostat Installation ...................................................36
2.01 Start-up Procedure.......................................................................37
Appendix A Ratings and Data ....................................................................... A-1
Appendix B Base Stand Installation .............................................................. B-1
Appendix C Free Blow and Wet Heat Plenum Installation for VWCA............ C-1
Appendix D Free Blow Plenum Installation for VWIA .................................... D-1
Appendix E Trim Strip Installation ................................................................. E-1
Appendix F Wall Bracket Installation............................................................. F-1
Appendix G Outdoor Louver/Collar Installation..............................................G-1
Appendix H Sound Reduction Panel ............................................................. H-1
Appendix I Electric Heat Installation ..............................................................I-1
Appendix J Check, Test and Start Form ........................................................J-1

GeoScholar (I&S) 03/2019 15700 - 4 HVAC Equipment
SECTION 15700
HEATING, VENTILATING AND AIR CONDITIONING EQUIPMENT
1.01 TOOLS/FIELD FURNISHED SUPPLIES
WARNING
TO AVOID PERSONAL INJURY, ADEQUATE PROTECTIVE CLOTHING MUST BE WORN
AND PRECAUTIONS IN HANDLING AND INSTALLING THIS EQUIPMENT MUST BE
PRACTICED AT ALL TIMES.
•Power Drill/Driver & Extension
•T25 TORX Bits
•Needle Noise Pliers
•Wire Stripper/Cutter
•Spirit Level
•Tape Measure
•Screwdriver with Slotted Bit
•Caulk Gun
•Sealant Caulk (tube)
•Wire Nuts for Power and Control Wiring Gauges
•Supplies to Install PVC Condensate Drain
•Floor Fasteners for Cabinet (4 required for 1/2” pass through holes) - Appropriate Drivers
for Floor Fasteners
•Supplies to Install Wet Heat Coil (Hot Water) (if appropriate)
•25 Ft. of Polyurethane Foam Strips, 1” Wide x 1/2” Thick, Adhesive Backing, for
GeoScholar /Wall Interface.
1.02 INSPECTION/UNPACKING/HANDLING
A. The GeoScholar heat pumps are shipped to the job site on 4x4 wood base framing,
and enclosed in shrink wrap.
Freeblow and ducted plenums are shipped on wooden skids and enclosed in shrink
wrap.
Outdoor louvers/collar assemblies, louvers and collars are shipped in corrugated
containers.
Base stands are shipped on a wooden skid and are enclosed in shrink wrap.
Trim pieces are enclosed in corrugated carton and strapped to a wooden skid.
The sound reduction panel (models VWCA & VWCSA only) is shipped in a wooden
crate after being shrink wrapped.
!

GeoScholar (I&S) 03/2019 15700 - 5 HVAC Equipment
B. Immediately upon delivery to the jobsite, each GeoScholar heat pump and
the appropriate additional accessories should be inspected for visible and
concealed damage. All damage must be reported to the freight carrier within 15
days, on the freight carrier’s form.
The GeoScholar heat pump and additional accessories should be stored inside and
not exposed to outdoor weather conditions. Do not remove equipment from packing
until it is ready to be installed.
CAUTION
DO NOT STACK THE UNIT OR ANY ACCESSORIES ON TOP OF ONE ANOTHER.
THE UNITS SHOULD ALWAYS REMAIN IN THE UPRIGHT POSITION WHEN BEING
SHIPPED, STORED, HANDLED OR INSTALLED.
DO NOT STORE THE UNIT OR ACCESSORIES IN OUTDOOR
WEATHER CONDITIONS.
IF IT IS NECESSARY TO TILT THE GEOSCHOLAR HEAT PUMP WHILE MOVING IT
DURING INSTALLATION, BE SURE THE TOP END IS ALWAYS ABOVE THE BOTTOM
BY AT LEAST 30 INCHES. THE UNIT SHOULD NOT BE ALLOWED TO REMAIN IN
THE TILTED POSITION ANY LONGER THAN REQUIRED FOR THE ACTUAL MOVING
PROCESS.
C. Note the unit identication label is located on left side cabinet panel at the lower front
corner. The identication label has the model and serial number on it and the type of
refrigerant and amount of refrigerant charge.
IMPORTANT
WHEN THE HEAT PUMP IS INSTALLED, MODEL NUMBER AND SERIAL NUMBERS
ARE TO BE RECORDED ON THE COVER OF THIS MANUAL AND MAINTAINED
IN A LOCATION FOR IMMEDIATE ACCESS, WHEN REQUESTING FURTHER
INFORMATION CONCERNING THIS EQUIPMENT.
Serial Number Date Code
A = January G = July L = 2000 T = 2006
B = February H = August M = 2001 U = 2007
C = March J = September N = 2002 V = 2008
D = April K = October P = 2003 Y = 2009
E = May L = November R = 2004 Z = 2010
F = June M = December S = 2005 A = 2011
!

GeoScholar (I&S) 03/2019 15700 - 6 HVAC Equipment
For the GeoScholar heat pump system, the identication numbering system is
shown below. The model identication number is located as shown in Figure 1.
Models with an “S” indicate a 2-stage compressor. Installation is identical for the
heat pumps regardless of the type of compressor. However, a 2-stage cooling
thermostat must be used with all 2-stage compressor units.
VWI = GeoScholar III Series
VWC - GeoScholar QV Series
Power Vent with
Motorized Damper Special Options
G =Hot Gas Reheat/Dehumidification
VW•
40 =39,000 BTUH
48 =47,000 BTUH
60 =56,500 BTUH
System Ty pe
J =
Nominal Cooling
24 =23,500 BTUH
30 =30,000 BTUH
36 =35,000 BTUH
HP = Heat Pump
Power Supply
A=208/230V,1,60Hz
C =208/230V,3,60Hz
D= 460V,3,60Hz
Configuration
N= Manual Damper (std)
H=GreenWheel®ERV
B =Motorized Damper
Heat – kW
00 15
05
7.5
99 (Hot Water)
10
•••• •
HP
GG = Tw o Stage Hot Gas Reheat
Refrigerant
A = R-410A
Refrigerant
A
S = 2-Stage Compressor
S
Figure 1. General External Component Identication and Access to GeoScholar
QV Series Heat Pump

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1.03 CONTROLS
1.03A. STANDARD CONTROLS
1. Programmable Logic Controller (PLC) Microprocessor
GeoScholar heat pumps use a factory installed PLC microprocessor to control the
operation, the safety switches and function options. LED’s show operational status
and provide assistance with diagnosis if troubleshooting is ever required. Various
control functions are eld selectable. The PLC is also capable of communicating
to PLC’s in other GeoScholar units to allow run time leveling and does not require
additional equipment installed in the GeoScholar unit. The PLC microprocessor
provides improved reliability because of the reduction of components, the
components utilized are more durable and the control box wiring has been simplied.
Pertinent statistical data about the life of the refrigeration system can be accessed
through the PLC.
The PLC microprocessor provides for the following control and operation functions:
• Anti-Short Cycle Timer - Prevents the compressor from destructive short
cycling due to momentary power interruptions. One of three time intervals can
be eld selected.
• BAS Control Relay - Provides 24 VAC coil to control operation from Building
Automation System (BAS). Note - an additional BAS control relay can be
added when 120 or 240 VAC coils are required.
2. High and Low Refrigerant Pressure and Loss of Charge Switches
These switches render the compressor and pump inoperative whenever the limits of
the pressure switches are exceeded. In the event of high pressure, the GeoScholar
heat pump will turn off and lockout.
The low pressure (A/C) and loss of charge (HP) switch render the compressor and
pump inoperative whenever the limit of the switch is exceeded after one minute.
The high and low pressure and loss of charge switches are resettable at the wall
thermostat or by turning power off and then on to the GeoScholar heat pump. A fault
LED located on the PLC indicates that a lockout has occurred and whether it is due
to high or low refrigerant pressure.
3. The indoor blower fan speed control (VWCA models only) provides adjustable air
volume from the indoor blower.
4. The motorized fresh air damper with PowerVent and GreenWheel® ERV
ventilation options are equipped with a fresh air fan speed control. The fresh air
fan speed control controls both the ventilation intake and exhaust blowers together,
automatically balancing the intake and exhaust cfm up to 450 cfm.

GeoScholar (I&S) 03/2019 15700 - 8 HVAC Equipment
5. Fresh water/anti-freeeze solution switch. This two position selector switch must be
set based upon the liquid used for the heat source. If the system is using fresh water,
select fresh water. If the system is using an antifreeze solution, e.g. glycol, select
anti-freeze solution. Brine or salt solutions should NOT be used due to corrosion of
the heat exchanger.
6. Freeze Stat. A thermostat clamped to the outlet water line of the water coil senses
the temperature of the water. If the sensor detects water temperature of 37°F or lower
and the compressor and pump are on, the compressor is turned off, but the pump will
continue to run. If the compressor and pump are off when a temperature of 37ºF is
detected, the pump will be turned on. The freeze stat is disabled (not operable) if the
antifreeze solution position is selected in “F” above.
1.03B OPTIONAL CONTROLS
1. All units have the following control options available.
A. The spring wound timer is a eld installed kit used to enable operation of the
heat pump for up to six hours, or override the building automation system. (p/n
08557)
B. The motorized fresh air damper with PowerVent and GreenWheel® ERV
ventilation options can be equipped with an exhaust fan air speed control, which
controls the ventilation exhaust blower independent of the fresh air intake blower.
1.04 CONTROLLERS
1.04A THERMOSTATS & SUB-BASES
1. GeoScholar™ heat pumps with one stage of heat. All units with 2-stage compressors
require a two stage cool thermostat.
A. Digital, non-programmable thermostat (p/n 50121). One stage heat, one
stage cool. Fan switch: Auto & On. Manual changeover system switch: Cool-Off-
Heat. Low temperature protection. °F or °C selectable. Thirty minute power loss
memory retention.
B. Digital, seven day programmable thermostat (p/n 50123). One stage heat, one
stage cool. Fan switch: Auto & On. Auto-changeover. Keypad lockout. Non-volatile
program memory. Title 24 compliant.
C. Digital, non-programmable thermostat (p/n 50186). One stage cool/one stage
heat. Manual or auto changeover. Fan mode: Auto or On. Permanent retention
of settings upon power loss. Field adjustable temperature calibration. Max heat
and minimum cool set points. Adjustable temperature differential. Remote sensor
capable. Keypad lock out. Status LED. °F or °C selectable.
IMPORTANT
MINIMUM AIR FLOW IS REQUIRED FOR PROPER OPERATION.

GeoScholar (I&S) 03/2019 15700 - 9 HVAC Equipment
2. Thermostat guards.
A. Clear thermostat guard with keylock & clear plastic cover & base (p/n
50092). For use with 50121, 50123, 50186, 50107 & 50252 thermostats.
B. Clear thermostat guard with keylock & clear plastic cover & base (p/n 50119).
For use with 50248 thermostat.
1.04B HUMIDITY CONTROLLERS
1. Humidity Controller
A. Digital humidity controller, (p/n 50254). To be used with units with hot gas or
electric reheat. Programmable dehumidistat, humidistat and ventilation control.
Time of day can be set for dehumidifier, humidifier or ventilation to run. Auto
changeover for humidification or dehumidification. Permanent memory retention of
set points. Humidity sensor can be field calibrated. High & low dehumidification set
points. Outdoor temperature and humidity sensor included. ºF or ºC selectable.
1.04C ENERGY MANAGEMENT SYSTEMS
1. MAR5000 Energy Management System provides a number of functions while
remaining extremely cost sensitive. For a complete description of the operation and
features of the MAR5000 EMS, please see the MAR5000 Product Data Sheet. The
MAR5000 features:
• Temperature control.
• Dynamic recovery time.
• Run time limitation of heat pump to minimize energy costs.
• Humidity measurement and direct control of the dehumidication function.
• Seven relays for interfacing with the HVAC system or external devices.
• Ventilation control.
• One dry contact set of inputs enables data feed from any dry contact output
device, e.g., a door switch.
• Support for peak load shedding.
• A precise time clock that will keep accurate time for lengthy power outages
(at least 2 1/2 weeks).
• Intelligent occupancy and departure anticipation.
Options include:
• Unoccupied continuous fan shutoff.
2. The direct digital control (DDC) interfaces with the building automation system
(BAS) is to be dened by the specier, in consultation with the Marvair®sales
representative. Marvair will factory install the DDC sent by the DDC manufacturer,
and purchased by the customer.

GeoScholar (I&S) 03/2019 15700 - 10 HVAC Equipment
1.05 OPTIONS
1.05A TWO STAGE COMPRESSOR
1. Models with a “S” in the in the 5th letter of the model number have a 2-stage
compressor. A two stage compressor is able to maintain more precise temperature
control and humidity levels. The 2-stage operation is only operational in the cooling
mode-heating and dehumidication are 1-stage.
Installation of heat pumps with a 2-stage is identical to hose with a 1-stage
compressor. However, a 2-stage cooling thermostat must be used. Do not use the
Mar5000 controller with a unit with a 2-stage compressor.
1.05B WATER SIDE ECONOMIZER (VWIA MODELS ONLY)
1. A water side economizer is a factory installed option that can reduce the cost of
cooling the classroom. The water side economizer is a set of water coils installed
in the plenum. If the loop water is sufciently cool and cooling is required by the
room thermostat, a valve opens to allow the cool water to ow into the coils.
Simultaneously, the indoor blower turns on to pull the air across the coils and into the
classroom. When either the room temperature is satised or the entering water rises
above the set point, the economizer operation is terminated. The following schematic
shows the internal water piping for the waterside economizer.
Figure 2. Water Side Economizer
L
oop
W
a
t
er
Senso
r
Notes:
PLENUM - WATERSIDE ECONOMIZER
Hose
FlexibleFlexible
COIL-NC
Connect to Hi
g
h Pressure
1" MPT Water Out
Pressure-Actuated
1" MPT Water In
Water-Regulating
Valve
24 Vol
t
2-WAY
Signal
Heating
3
Refrigerant Liquid Line
LH WATERSIDE ECONOMIZER
Hose
Co-Axial
1
RH WATERSIDE ECONOMIZER
3-WAY
COIL-NC
Heat Exchanger
2
Tem
p
erature
Controller
DASHED LINES ( ) REPRESENT EVERYTING INSIDE OF PLENUM

GeoScholar (I&S) 03/2019 15700 - 11 HVAC Equipment
1.06 LOCATION PREPARATION
WARNING
THE GEOSCHOLAR HEAT PUMP MUST BE INSTALLED IN CONFORMANCE WITH ALL
APPLICABLE LOCAL AND NATIONAL ELECTRICAL, PLUMBING AND BUILDING CODES.
A. The GeoScholar heat pump must be installed on an outside wall for access to outside
air when the GeoScholar unit is providing fresh air for ventilation. The wall opening
dimensions are shown in Figure 3. It must not interfere with any windows or doors
to the outside. The outdoor air path must not be impeded by shrubbery or other
obstructions. Do not locate the GeoScholar heat pump where noxious fumes or gas
can be drawn in from the outdoor air and introduced in the classroom.
The GeoScholar heat pump must be installed on a hard, level, smooth surface such
as concrete, wood or tile. Do not install the unit on a carpeted surface.
To remove carpet from where the “footprint” of the unit will be, when installed,
carefully measure, cut and remove carpet from an area based on the dimensions of
the GeoScholar cabinet as described in Figures 4 and 5; and allowing for any offset
or standoff from the nished interior surface of the wall.
Prior to installation of the GeoScholar heat pump, provisions are to be made for the
following, as appropriate.
1. Wall opening dimensions for the GeoScholar heat pump are as shown in Figure
3. The unit is designed for installation through a 14 inch thickness nished wall.
For nished wall depth less than 14 inches, the unit will stand off from the interior
nished wall and it will be necessary to order and install trim pieces to provide a
nished, color coordinated enclosure that ts ush to the interior wall.
Figure 3. Wall Opening Dimensions for GeoScholar Heat Pump
1.07 POWER AND CONTROL WIRING (ROUGH-IN)
A. Line voltage power supply must be sized to provide adequate power for the
operation of the specic model heat pump and, if chosen, the electric heat option.
Information on line power requirements, line sizing and fuse sizing is shown on data
!
MODEL All Units
A 36.75
B 8.00
C 32.00
C* 36.00
*When 4”high base stand is used, the C*
dimension is specied.
Dimensions are in inches.

GeoScholar (I&S) 03/2019 15700 - 12 HVAC Equipment
or rear. The locations of the knockouts for power leads are shown in Figures 4 - 6.
Depending on the location of the GeoScholar heat pump relative to the outside wall,
the exact rough-in location for power lines in the school room can be determined. Six
feet of power line should be available inside the cabinet for routing and connecting
the power lines, after the GeoScholar unit is installed. If entry is from bottom, the
stub-out should be no higher than 1/2” from the classroom oor to allow the unit to
slide into the wall opening.
B. Low voltage wiring can be roughed in to either the back (outside wall) or bottom
(oor) of the cabinet. Six feet of low voltage wire should be available for routing and
termination within the unit. If the entry is from the bottom, the stub-out should be no
higher than 1/2” from the classroom oor to allow the GeoScholar heat pump to slide
into the wall opening. Reference Figures 4 -6 as noted above, for control wiring entry
points into the cabinet.
label on unit. The power leads can enter the heat pump either through the bottom

GeoScholar (I&S) 03/2019 15700 - 13 HVAC Equipment
Figure 4. GeoScholar Heat Pump Models VWCA24/30/36
Dimensional Data
NOTE: ACTUAL LOCATION OF WATER INLET AND OUTLET WILL VARY WITH SPECIFIC
GEOSCHOLAR UNIT.
BASE VIEW
CONDENSATE
DRAIN K.O. PLATE
ELEC. K.O.
PLATE
FRONT
1 5/8
3 1/2
1 7/8
8 1/2
4
2 7/8
6
11
13 3/4
2 3/4
2
WATER INLET/OUTLET
IN BASE OF UNIT 1 1/2" OPENINGS
OUTLET DUCT
7 7/8
6 1/8
9 1/8 9 1/8
(ON DUCTED PLENUM ONLY)
USE 28" X 8" DUCT WORK TO
CONNECT TO DUCTED PLENUM
27 7/8
FRONT
TOP VIEW
35 3/4
2 3/4
4 1/4
2
WATER INLET/OUTLET
IN TOP OF UNIT 1 1/2" OPENINGS
APPROX.
REAR
GRILLE, EXHAUST AIR
GRILLE, RETURN AIR
FRONT VIEW
GRILLES
AVAILABLE
PLENUM ONLY
ON FREEBLOW
FRONT AND SIDE
3
7/8Ø TUBING
IF USING BASE OPENING
33
RIGHT SIDE VIEW
101
16
20
33 1/8
1
7 7/8
6 1/8
OUTLET DUCT
(ON DUCTED PLENUM ONLY)
SIDE GRILLE
85
6
46
13
SHOWN WITH OPTIONAL PLENUMS
REAR VIEW
46 1/8
3
4
2 1/2
3 1/2
2
(FREEBLOW AND DUCTED) FOR
ILLUSTRATION ONLY.
3 1/2
2
APPROX.
42
IN BACK OF UNIT 1 1/2" OPENINGS
WATER INLET/OUTLET
DRAIN K.O.'s
CONDENSATE
ELECTRICAL K.O.'s

GeoScholar (I&S) 03/2019 15700 - 14 HVAC Equipment
NOTE: ACTUAL LOCATION OF WATER INLET AND OUTLET WILL VARY WITH SPECIFIC
GEOSCHOLAR UNIT.
Figure 5. GeoScholar Heat Pump Model VWCA40/48/60
Dimensional Data
6 1/4
1 7/
8
7
5 3/4
6
7 7/8
4
CONDENSATE
K.O. PLATE
ELECTRICAL
K.O. PLATE
4BASE VIEW
FRONT
16 3/8
8 1/2
WATER INLET/OUTLET
IN BASE OF UNIT
2 1/2
2" OPENING
35 3/4
TOP VIEW
9 1/829 7/89 1/8
6 1/8 6 1/8
TO CONNECT DUCTED PLENUM
USE 30" x 10" DUCTWORK
(ON DUCTED PLENUM ONLY)
OUTLET DUCT
FRONT
9 3/4
9 7/8
9 3/4
WATER INLET/OUTLET
IN TOP OF UNIT 2" OPENINGS
4 3/4
2 1/2
3 1/2
48
90
FRONT VIEW
48 1/8
ON FREEBLOW PLENUM
GRILLES AVAILABLE
FRONT AND SIDE
ONLY
33
29 1/8 13
RH SIDE VIEW
29 1/4
SIDE GRILLE
16
106
6
51
REAR VIEW
6 3/4
4 1/22 1/8
6 5/8
10 3/8
CONDENSATE
3/4 X 1.0 K.O.'s
ELECTRICAL
3/4 X 1.0 K.O.'s
2 1/2
4 1/8
43 1/4
FRESH AIR
INTAKE
EXHAUST
AIR
WATER INLET/OUTLET
IN BACK OF UNIT
2" OPENING

GeoScholar (I&S) 03/2019 15700 - 15 HVAC Equipment
Figure 6. GeoScholar Heat Pump Model VWIA24-60
Dimensional Data

GeoScholar (I&S) 03/2019 15700 - 16 HVAC Equipment
1.08 CONDENSATE DRAIN LINE (ROUGH-IN)
A. The condensate drain line can be roughed in to drain the GeoScholar heat pump
from either the back (outside) or the bottom (oor). The locations for the condensate
stub-outs can be determined from the cabinet knockouts identied in Figures 4/5/6.
The factory installed condensate connection within the cabinet is a female PVC
tting designed for a 3/4” slip connection.
CAUTION
INSPECT THE FLEXIBLE CONDENSATE DRAIN LINE INSIDE THE GEOSCHOLAR
UNIT (WHEN INSTALLED) FOR POSSIBLE TUBING COLLAPSE. CORRECT AS
APPROPRIATE.
TO PREVENT CONDENSATE OR RAIN WATER FROM RUNNING DOWN THE INTERIOR
OF THE WALL, INSTALL FLASHING UNDER THE OUTDOOR AIR BOX OVER
THE SILL OF THE WALL OPENING.
THE SECONDARY CONDENSATE LINE ON THE VWCA24, 30 & 36 IS TERMINATED
IN THE BOTTOM OF THE UNIT. THIS LINE MUST BE EITHER ROUTED OUT OF THE
GEOSCHOLAR UNIT TO A SUITABLE LOCATION OR TEED INTO THE PRIMARY
CONDENSATE LINE. FAILURE TO ROUTE THE CONDENSATE OUT OF THE UNIT,
COULD RESULT IN EXTENSIVE WATER DAMAGE.
THE SECONDARY CONDENSATE LINE IN THE VWCA40, 48 & 60 UNITS SHOULD BE
RUN THROUGH THE OUTDOOR AIR BOX AND THROUGH THE EXTERNAL LOUVER.
ROUTE THE CONDENSATE DRAIN AWAY FROM THE GEOSCHOLAR UNIT WITH
SUFFICIENT DOWNWARD SLOPE TO INSURE ADEQUATE DRAINAGE.
THE VWIA DOES NOT HAVE A SECONDARY DRAIN.
1.09 WET HEAT (ROUGH-IN)
A. Hot water coil connections are made by dropping supply and return lines through the
knockout locations in the top of the plenums, as described in Figures 4 and 5 for the
heat pump. Access to the interior cabinet is through these factory-notched locations.
1.10 PREPARATION OF THE GEOSCHOLAR HEAT PUMP
WARNING
TO AVOID PERSONAL INJURY, ADEQUATE PROTECTIVE CLOTHING MUST BE WORN
AND PRECAUTIONS IN HANDLING AND INSTALLING THIS EQUIPMENT MUST BE
PRACTICED AT ALL TIMES.
After the rough-in is complete, the GeoScholar heat pump and accessories must
be prepared for nal installation prior to start-up. The following items are to be
completed prior to nal installation.
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GeoScholar (I&S) 03/2019 15700 - 17 HVAC Equipment
A. Remove the lower front panel of the GeoScholar heat pump for access to the
shipping skids. Unscrew the four hold-down lag bolts from the inside of the unit. The
four lag bolts on all the the VWIA models and the VWCA24-30-36 can be accessed
from the front of the unit. On the VWCA40-48-60, the front two lag bolts can be
accessed from the front of the unit. The back two lag bolts can be accessed through
the condensate opening in the rear of the unit. Remove the cover plates to access
the bolts.
Remove the shipping skids from under the GeoScholar heat pump.
B. If the base stand accessory was chosen, install the base stand in accordance with
installation instructions included with the base stand or see Appendix B at end of
manual.
C. Hot Water Plenum. The protective lm on top of the GeoScholar cabinet and on the
plenum must be removed to install the plenum. Fasten the plenum to the top of the
cabinet in accordance with the instructions included with the plenum or Appendix C at
end of manual.
D. Electric Heaters. On the 2, 2½, 3 and 3½ ton VWCA units, electric heaters are
shipped attached to the top of the unit. Remove the metal shipping plate from the
electric heat assembly mounted on top of the cabinet. Remove protective shipping
plate over electric heater and check for damage before connecting power to the unit.
Reference the tag afxed to the shipping plate on top of the cabinet for directions.
On 4 & 5 ton VWCA units and all VWIA units, the electric heaters are shipped inside
the heat pump in the lower compartment. Please see Appendix I for installation
instructions for electric heaters for all VWIA units.
Figure 5. Tag for Plate Removal Attached to Protective Plate on Electric Resistance
Heat Element at Top of the GeoScholar Cabinet.
ATTENTION: “INSTALLER”
REMOVE PROTECTIVE SHIPPING
PLATE OVER ELECTRIC HEATER
BEFORE CONNECTING POWER TO
UNIT. CHECK FOR DAMAGE.
E. Freeblow Plenum/Ducted Plenum. Install plenum to top of cabinet after shipping
plate has been removed from electric heater (if appropriate). Instructions are
included with plenum or see Appendix C at end of manual.
The air distribution system which is eld supplied and installed downstream of the
specied ducted plenum must be engineered to assure sufcient air ow, even
under adverse conditions, such as dirty lters. The information provided in Figure 1,
Appendix A should be used to design the air distribution system duct size leaving the
GeoScholar heat pump, keeping the external static pressure to a minimum.
Applications using duct work should be designed and installed in accordance with the
current edition of the National Fire Protection Association codes and standards 90A

GeoScholar (I&S) 03/2019 15700 - 18 HVAC Equipment
IMPORTANT
BE SURE TO SEAL THE OPEN AREAS BETWEEN LINES ENTERING THE GEOSCHOLAR
CABINET AND THE KNOCKOUT OPENINGS, TO PREVENT AIR LEAKAGE.
I. If the heat pump is to t ush against the inside of the exterior wall, cut to length,
strips of open cell polyurethane foam 1” wide by 1/2” thick with adhesive backing,
eld supplied, on one side. This may be applied to the back of the heat pump and
plenum along and ush with the two vertical and top horizontal edges. These strips
will provide a nished appearance to the wall/heat pump interface and provide a seal
between the equipment and wall. If the heat pump is applied with a side against a
wall (in a corner), use the same strip material on the end panel along the side vertical
edge.
J. Prior to sliding the GeoScholar heat pump into the wall opening, check to be sure
that the oor surface is hard, smooth and level (concrete, wood, vinyl tile or the
equivalent). If the oor is carpeted, cut out an appropriate “footprint” based on the
Figure 3 or 4 drawings and the location of the unit relative to the inside nished wall
(ush or offset). Be sure the surface is level or provisions are made to level the unit
upon installation.
K. On 4 & 5 ton VWCA units and all VWIA units, the outdoor air box must be eld
and 90B. The duct system must be engineered to insure sufcient air ow through
the unit to prevent over-heating of the heater element. This includes proper supply
duct sizing, sufcient quantity of supply registers, adequate return and lter area.
Ductwork must be of correct material and must be properly insulated. The duct work
must be constructed of galvanized steel with a minimum thickness of .019. Ductwork
must be rmly attached, secured and sealed to prevent air leakage. Do not use duct
liner on inside of supply duct within four feet of the unit.
Galvanized metal duct extensions should be used to simplify connections to ductwork
and grilles. Use fabric boots to prevent the transmission of vibration through the duct
system. The fabric must be U.L. rated to a minimum of 197°F.
F. Install the outdoor louver/collar assembly to the outdoor side of the wall opening.
The louver/collar assembly may be fastened to the air box (or air box extension) as
described in the instructions for outdoor louvers/collars. The louver must be installed
with the blades pointing downward on the outside and the louver and the collar must
be water sealed to the outside wall surface with the appropriate caulking material.
See the instructions that come with the outdoor louver for installation details or see
Appendix F at the end of this manual.
G. Weather Panels are eld supplied and do not come with the GeoScholar heat pump.
If a weather panel covers the wall opening described in Figure 2, remove the weather
panel prior to installing the unit into the wall opening.
H. After measuring for correct locations of power/control wiring entry, condensate drain
line, and the appropriate wet heat lines, remove the appropriate knock-out access
ports from the cabinet. Be sure they align with the rough-in points for the noted
pipes and wires. Be sure electrical, condensate and wet heat piping will not cause
interference or be damaged by sliding the GeoScholar heat pump into place.

GeoScholar (I&S) 03/2019 15700 - 19 HVAC Equipment
WARNING
WHEN FASTENING LOUVER/COLLAR ASSEMBLY TO AIR BOX, DO NOT
OVERTIGHTEN LOUVER SCREWS. OVERTIGHTENING SCREWS WILL CAUSE
DAMAGE AND WARP THE LOUVER/COLLAR ASSEMBLY.
C. Check (with a spirit level) to see that the heat pump is level and plumb. If it is not, take
the appropriate corrective action to level and plumb the system. 1/8” thick washers
installed. Install the outdoor air box onto the back of these GeoScholar heat pumps
before sliding the unit into position. Apply a weather-proof sealant; i.e., silicone,
onto the back of the GeoScholar heat pump prior to installing the outdoor air box to
prevent water leaks.
1.11 INSTALLATION THROUGH THE OUTSIDE WALL.
A. Slide the GeoScholar heat pump into the wall opening slowly, being careful to clear
the appropriate stubouts. The heat pump, when installed properly, should have a
clearance between the air box outside edge and the nished outside wall as shown in
Figure 7. Proper t up of the louver/collar assembly to the air box to the outside wall
requires the noted recess dimension to be maintained after installing the unit.
B. To minimize sound in the classroom, insulate all four sides of the outdoor air box that
is internal to the classroom with the following:
Layer 1: 1/2” Rubatex
Layer 2: 1-1/2: Duct Board
Figure 7. Dimension Between GeoScholar Heat Pump Air Box and Finished Outside
Wall for Outdoor Louver/Collar Assembly Installation
(Note: model VWCA shown, but dimensions are the same for the VWIA.)
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NOTE: To prevent condensate OR RAIN WATER from running down the interior of the wall,
install ashing under the outdoor AIR BOX over the sill of the wall opening.
FREEBLOW PLENUM
DISTANCE (INCHES) BETWEEN AIR BOX
AND OUTSIDE FINISHED WALL
LOUVER/COLLAR
OUTSIDE WALL
NOTE: TO PREVEN CONDENSATE OR RAIN WATER FROM RUNNING
DOWN THE INTERIOR OF THE WALL, INSTALL FLASHING UNDER
THE OUTDOOR AIR BOX OVER THE SILL OF THE WALL OPENING.

GeoScholar (I&S) 03/2019 15700 - 20 HVAC Equipment
!
with 1/2” pass through holes can be installed appropriately under the fastener holes in
the base of the heat pump to make the system level and plumb.
D. Secure the heat pump to the oor with appropriate eld supplied fasteners, through the
four 1/2” diameter through holes in the base.
E If the GeoScholar heat pump is offset from the outside wall, trim strips should be
installed at this time. Check instructions that come with trim strips for installation or
see Appendix D at end of this manual.
F. If appropriate, install wall brackets to the inside surface of the outside wall and to the
cabinet of the GeoScholar unit, at this time. Check instructions with wall brackets for
installation or see Appendix E at end of this manual.
1.12 ELECTRICAL, CONDENSATE, WATER AND WET HEAT HOOK-UPS
WARNING
ALL ELECTRICAL AND PLUMBING FITTING AND REFRIGERATION WORK MUST
MEET THE REQUIREMENTS OF LOCAL AND NATIONAL CODES AND ORDINANCES.
WORK SHOULD BE DONE ONLY BY PROFESSIONALLY QUALIFIED AND TRAINED
SERVICE PEOPLE.
IMPORTANT
STUBOUTS SHOULD BE LOCATED (FROM THE FLOOR OR WALL) TO BE DIRECTLY
OPPOSITE THE SELECTED CABINET KNOCKOUT ON THE CABINET, AS SHOWN IN
FIGURES 3/4/5. THIS IS A REQUIREMENT IF A BASE STAND IS TO BE INSTALLED
AND STUBOUTS ARE COMING THROUGH THE FLOOR.
A. 1. For line voltage wiring, the power supply must have the correct voltage, phase
and ampacity for the selected GeoScholar unit. Check the data label on each
GeoScholar unit to determine these values.
Be sure that the power to the line voltage wiring is off prior to hooking-up the
wiring within the GeoScholar cabinet. Remove the lower front panel for access
to the disconnect on the VWCA models. On the VWIA models, the disconnect is
located behind the right door. Figures 8a and 8b illustrate the disconnect location
with the lower front panel removed. Turn the disconnect to “OFF” position.
Remove the middle front panel for access to the control center. On the VWIA
models, the control center is located behind the right door. The electrical
schematic for the heat pump is contained in a pocket on the inside of the middle
front panel door. Figure 9 shows typical control centers for the GeoScholar heat
pump. Figures 10a and 10b show typical single and three phase wiring diagrams
for the GeoScholar heat pump.
2. Power supply service must be with the allowable voltage range stamped on the
identication plate. To operate a nominal 230/208V model on 208V, change
the transformer line tap from 240V to 208V, following the instructions on
the electrical schematic.