Marvair Scholar III™ VAISA I&S Manual 03/2019 Rev. 8
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THE INTERNAL TRANSFORMER IS NOT DESIGNED TO
POWER OTHER EXTERNAL DEVICES.
3. For Scholar III™ heat pump or air conditioner that interfaces with a building
automation system (BAS) or energy management system (EMS), detailed
instructions for the specific system being installed will be supplied separately by
the manufacturer of the BAS/EMS system.
The control of the GreenWheel
®
ERV or Ventilation relay (VR) and the
energy management relay (EMS) are 24 volt inputs to the PLC. If 120 V. of
240 inputs are required, additional relays must be installed in the factory or
in the field.
The unit control system is factory wired to operate upon an input signal from any
appropriate 24 VAC control thermostat or DDC control system. If unit shutdown
is desired during unoccupied periods of the temperature controlled space it may
be accomplished by the following: The Controls Contractor must provide a set
of contacts (24 VAC pilot duty) between terminals E1 and E2. When the field
supplied contacts between E1 and E2 are closed the system will shut down.
The unit control system is factory wired to energize the ventilation package
anytime the Indoor Fan/Blower is energized. If additional control of the ventilation
package is desired, it may be accomplished by the following: The Controls
Contractor must remove the factory installed jumper between terminals V1 and
V2 then provide a set of contacts (24 VAC pilot duty) between terminals V1
and V2. When the field supplied contacts between V1 and V2 are closed the
ventilation package will operate when the Indoor Fan/Blower is energized.
4. For models with an internal thermostat, no internal control wiring is required.
W2
G
X
H
E
R
A
Y
O
W2
G
C
R
A
Y
O
HEA
T
PUMP*
LOW VOL
T
AGE SECTION
Thermostat
Field Supplied
Seven (7) Conductor, Color Coded
18 Gauge Thermostat Cable
Blue
Red
Humidity Controller
Yellow
To Pigtail from
HUM on PLC
*A/C’
s do not have “O”.
W2
G
X
H
E
R
A
Y
O
W2
G
C
R
A
Y
O
Thermostat
Field Supplied
Seven (7) Conductor, Color Coded
Thermostat Cable
Scholar QV™ Heat Pumps and Air Conditioners
Note: A/C’s do not have “O”.
Figure 9a. Humidity Controller
Wiring Detail
Figure 9. Remote Wall Mounted
Thermostat Wiring Detail
