Specifications

VCES-ERV-IOM-3B – Indoor ERV
10
Electrical Requirements
Location of wire connections required are shown in Ap-
pendix C.
A junction box or disconnect switch must be field supplied
where line voltage connections are made. Consult the
local building electrical codes for the proper selection of
power disconnect device(s).
A low voltage remote control wiring interface is provided
on the unit. The installer must provide wiring for the con-
trols that may be supplied optionally. The optional wall
controls require a four-wire LVT 24 gauge (or equivalent).
This control is 12 VDC. Other terminals are 24 VAC or dry
contact control. Terminals are available for the following
controls:
• Low-Com-High
– Makes dry contact for speed setting.
• Wall control
– Four-wire LVT 24 gauge minimum (12 VDC).
• Occupied (or night setback) timer/sensor
– Needs dry contact to operate. 24 VAC required
when timer is used. Do not use with Xtra wall
control.
• Enthalpy control
– 24VAC.
• Remote fan control
– Requires single pole, double throw switch.
• Dirty filter sensor
– Makes dry contact.
• Low temperature control
– Makes dry contact.
• Wheel rotation sensor
– Makes dry contact.
• CO
2
ventilation control
– Makes dry contact.
• Unoccupied recirc contacts
– 24 VAC.
• Smoke detector
– Makes dry contact.
For more information on the controls available for the
outdoor energy recovery ventilators, see the following Ap-
pendix E references:
• Wall Control Connection
• Occupied Timer/Sensor Connection
• Enthalpy Control
• Remote Fan Control
• Dirty Filter Sensor
• Wheel Rotation Sensor used as Low Temperature
Control (Wheel Failure)
• Wheel Rotation Sensor
• CO
2
Ventilation Control
• Unoccupied Recirc Contacts
• Smoke Detector
Recirculation Defrost
Recirculation defrost is a temperature initiated time based
cycle which will de-energize the exhaust fan and the
wheel drive motor, close the outdoor air damper and
circulate return air through both sides of the wheel. If re-
circulation is in operation, it will run approximately 15%
of the time, only when the outdoor air temperature falls
below 5°F [−15°C]. Please note that if the indoor relative
humidity is expected to be 30% or less, please contact a
Venmar CES representative or use the Venmar Select™
software as frost control may not be required.
Exhaust Only Defrost
Exhaust only defrost is a temperature initiated time-based
cycle which will de-energize the supply fan, close the
outdoor air damper and exhaust return air through the ex-
haust side of the wheel as it continues to rotate. If exhaust
only is in operation, it will run approximately 15% of the
time, only when the outdoor air temperature falls below
5°F [−15°C]. Please note that if the indoor relative humid-
ity is expected to be 30% or less, please contact a Venmar
CES representative or use the Venmar Select software as
frost control may not be required.
Electrical Connections
Start-up
Controls
Frost Control
WARNING
Unit cabinet must have an uninterrupted, unbroken elec-
trical ground to minimize the possibility of personal injury
if an electrical fault should occur. Failure to follow this
warning could result in the installer being liable for per-
sonal injury of others.
!