HE4XRT
Due to continuing product development, specifications are subject to change without notice.
© 2012 RenewAire LLC
134775_005 HE4XRTMan_Jan12.indd Revised 01/2012 www.renewaire.com
Page 9
E.
Control System with 2 Non-powered Relay Contacts: Use
this schematic if the external control system provides no
voltage or current at its output contacts. Install jumper
(provided) between terminals 2 & 3. Connect one side of
each of the output contacts to Terminal 1. Connect the
other side of the output contact to control the FA Blower
to Terminal 4, and the output contacts to control the EA
Blower to Terminal 5.
Control Wiring Schematics
NOTE: The simplified schematics below show only the relevant
portions of the low-voltage control circuit in the ERV unit and
representational external control approaches. See the
complete unit schematics elsewhere in this manual.
C.
Control Sending 24VAC “On” Signal (from an external
power source) to ERV: Make sure jumper is NOT installed
between Terminals 2 & 3. Now you safely can apply 24VAC
to the Terminals 3 & 4 to operate the ERV’s Isolation Relay
for OA/FA Blower. Install jumper (provided) between
terminals 4 & 5 to operate the ERV’s Isolation Relay for
the RA/EA Blower.
D.
Control operating on Unit’s 24VAC Power Supply: 24VAC
power is available at the Terminals 1 & 2. CAUTION:
external control system should not draw more than 8VA.
Install jumper (provided) between terminals 2 & 3.
Connect the switched output of the Control to Terminal
4 to operate the ERV’s Isolation Relay for OA/FA Blower.
Install jumper (provided) between terminals 4 & 5 to
operate the ERV’s Isolation Relay for the RA/EA Blower.
F.
Control System Sending two 24VAC “On” Signals from
an external power source: Make sure the jumper is NOT
installed between Terminals 2 & 3. Now you safely can
apply one of the 24VAC signals to Terminals 3 & 4 to operate
the ERV’s isolation relay for the Fresh Air Blower. Apply
the second 24VAC signal to Terminals 3 & 5 to operate the
ERV’s isolation relay for the Exhaust Blower (make sure the
polarity of each wire connected to Terminal 3 is the same).
Make sure the control provides no voltage or current at its
output terminals.
Supply only 24VAC (not VDC) from a Class II Power Source.
A.
Single 2-wire Control, unpowered: Use schematic below
if the control requires no power from the unit to operate
and acts like a simple on/off switch. The control must not
supply any power to the ERV unit. Install jumper (provided)
between terminals 2 & 3. Connect the control’s contacts to
terminals 1 & 4 to operate the ERV’s Isolation Relay for OA/
FA Blower. Install jumper (provided) between terminals 4 &
5 to operate the ERV’s Isolation Relay for the RA/EA Blower.
Supply only 24VAC (not VDC) from a Class II Power Source.
G. Control System Operating Isolation Dampers with End
Switches: Use Isolation Dampers with electrically separate
end switches. The end switches are used to separately
control the ERV unit’s Isolation Relays. This ensures that
each damper is open before the respective blower starts up.
NOTE: Because the ERV’s Motor Starters will only be
operating once the Dampers are open, the power draw
of the Damper Actuators is allowed to be as much as 35VA
while opening (including power draw of the external
control system, if any). However, the power draw of the
fully-opened (stalled) Actuators (and external control
system if any) must be less than 8VA. (Most damper
actuators have much lower power draws.)
B.
Single 2-wire Control on separate Power Supply, no power
present at Control Output: Wire as shown for the Single
2-wire control (A. above).
MPU
Connect Terminals 2 & 3
Connect Switch between Terminals 1 & 4
UNIT INTERNAL CONTROL WIRING
(SIMPLIFIED)
A SWITCH OR NON-POWERED
CONTROL USING UNIT'S 24VAC POWER
SUPPLY
UNIT INTERNAL CONTROL WIRING
(SIMPLIFIED)
24VAC FROM AN EXTERNAL SOURCE
Unit's 24VAC
Power Supply
UNIT INTERNAL CONTROL WIRING
(SIMPLIFIED)
AN EXTERNAL CONTROL USING UNIT'S
24VAC POWER SUPPLY
24VAC Available at Terminals 1 & 2
Unit's 24VAC
Power Supply
Unit's 24VAC
Power Supply
Connect Terminals 2 & 3
UNIT INTERNAL CONTROL WIRING
C
Isolation Relay Coil (Fresh Air)
(SIMPLIFIED)
A SWITCH OR NON-POWERED
CONTROL USING UNIT'S 24VAC POWER
SUPPLY
Unit's 24VAC
Power Supply
C
Isolation Relay Coil (Exhaust Air)
UNIT INTERNAL CONTROL WIRING
C
Isolation Relay Coil (Fresh Air)
(SIMPLIFIED)
TWO EXTERNAL RELAY CONTACTS
SUPPLYING 24VAC FROM AN
EXTERNAL SOURCE
Unit's 24VAC
Power Supply
C
Isolation Relay Coil (Exhaust Air)
C
Isolation Relay Coil (Fresh Air)
C
Isolation Relay Coil (Exhaust Air)
C
Isolation Relay Coil (Fresh Air)
C
Isolation Relay Coil (Exhaust Air)
C
Isolation Relay Coil (Fresh Air)
C
Isolation Relay Coil (Exhaust Air)
Connect Terminals 4 & 5
Connect Switch between Terminals 1 & 4
Connect Terminals 4 & 5
Connect Terminals 4 & 5
Connect Terminals 2 & 3
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
MPU
Connect Terminals 2 & 3
Connect Switch between Terminals 1 & 4
UNIT INTERNAL CONTROL WIRING
(SIMPLIFIED)
A SWITCH OR NON-POWERED
CONTROL USING UNIT'S 24VAC POWER
SUPPLY
UNIT INTERNAL CONTROL WIRING
(SIMPLIFIED)
24VAC FROM AN EXTERNAL SOURCE
Unit's 24VAC
Power Supply
UNIT INTERNAL CONTROL WIRING
(SIMPLIFIED)
AN EXTERNAL CONTROL USING UNIT'S
24VAC POWER SUPPLY
24VAC Available at Terminals 1 & 2
Unit's 24VAC
Power Supply
Unit's 24VAC
Power Supply
Connect Terminals 2 & 3
UNIT INTERNAL CONTROL WIRING
C
Isolation Relay Coil (Fresh Air)
(SIMPLIFIED)
A SWITCH OR NON-POWERED
CONTROL USING UNIT'S 24VAC POWER
SUPPLY
Unit's 24VAC
Power Supply
C
Isolation Relay Coil (Exhaust Air)
UNIT INTERNAL CONTROL WIRING
C
Isolation Relay Coil (Fresh Air)
(SIMPLIFIED)
TWO EXTERNAL RELAY CONTACTS
SUPPLYING 24VAC FROM AN
EXTERNAL SOURCE
Unit's 24VAC
Power Supply
C
Isolation Relay Coil (Exhaust Air)
C
Isolation Relay Coil (Fresh Air)
C
Isolation Relay Coil (Exhaust Air)
C
Isolation Relay Coil (Fresh Air)
C
Isolation Relay Coil (Exhaust Air)
C
Isolation Relay Coil (Fresh Air)
C
Isolation Relay Coil (Exhaust Air)
Connect Terminals 4 & 5
Connect Switch between Terminals 1 & 4
Connect Terminals 4 & 5
Connect Terminals 4 & 5
Connect Terminals 2 & 3
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
MPU
Connect Terminals 2 & 3
Connect Switch between Terminals 1 & 4
UNIT INTERNAL CONTROL WIRING
(SIMPLIFIED)
A SWITCH OR NON-POWERED
CONTROL USING UNIT'S 24VAC POWER
SUPPLY
UNIT INTERNAL CONTROL WIRING
(SIMPLIFIED)
24VAC FROM AN EXTERNAL SOURCE
Unit's 24VAC
Power Supply
UNIT INTERNAL CONTROL WIRING
(SIMPLIFIED)
AN EXTERNAL CONTROL USING UNIT'S
24VAC POWER SUPPLY
24VAC Available at Terminals 1 & 2
Unit's 24VAC
Power Supply
Unit's 24VAC
Power Supply
Connect Terminals 2 & 3
UNIT INTERNAL CONTROL WIRING
C
Isolation Relay Coil (Fresh Air)
(SIMPLIFIED)
A SWITCH OR NON-POWERED
CONTROL USING UNIT'S 24VAC POWER
SUPPLY
Unit's 24VAC
Power Supply
C
Isolation Relay Coil (Exhaust Air)
UNIT INTERNAL CONTROL WIRING
C
Isolation Relay Coil (Fresh Air)
(SIMPLIFIED)
TWO EXTERNAL RELAY CONTACTS
SUPPLYING 24VAC FROM AN
EXTERNAL SOURCE
Unit's 24VAC
Power Supply
C
Isolation Relay Coil (Exhaust Air)
C
Isolation Relay Coil (Fresh Air)
C
Isolation Relay Coil (Exhaust Air)
C
Isolation Relay Coil (Fresh Air)
C
Isolation Relay Coil (Exhaust Air)
C
Isolation Relay Coil (Fresh Air)
C
Isolation Relay Coil (Exhaust Air)
Connect Terminals 4 & 5
Connect Switch between Terminals 1 & 4
Connect Terminals 4 & 5
Connect Terminals 4 & 5
Connect Terminals 2 & 3
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
MPU
Connect Terminals 2 & 3
Connect Switch between Terminals 1 & 4
UNIT INTERNAL CONTROL WIRING
(SIMPLIFIED)
A SWITCH OR NON-POWERED
CONTROL USING UNIT'S 24VAC POWER
SUPPLY
UNIT INTERNAL CONTROL WIRING
(SIMPLIFIED)
24VAC FROM AN EXTERNAL SOURCE
Unit's 24VAC
Power Supply
UNIT INTERNAL CONTROL WIRING
(SIMPLIFIED)
AN EXTERNAL CONTROL USING UNIT'S
24VAC POWER SUPPLY
24VAC Available at Terminals 1 & 2
Unit's 24VAC
Power Supply
Unit's 24VAC
Power Supply
Connect Terminals 2 & 3
UNIT INTERNAL CONTROL WIRING
C
Isolation Relay Coil (Fresh Air)
(SIMPLIFIED)
A SWITCH OR NON-POWERED
CONTROL USING UNIT'S 24VAC POWER
SUPPLY
Unit's 24VAC
Power Supply
C
Isolation Relay Coil (Exhaust Air)
UNIT INTERNAL CONTROL WIRING
C
Isolation Relay Coil (Fresh Air)
(SIMPLIFIED)
TWO EXTERNAL RELAY CONTACTS
SUPPLYING 24VAC FROM AN
EXTERNAL SOURCE
Unit's 24VAC
Power Supply
C
Isolation Relay Coil (Exhaust Air)
C
Isolation Relay Coil (Fresh Air)
C
Isolation Relay Coil (Exhaust Air)
C
Isolation Relay Coil (Fresh Air)
C
Isolation Relay Coil (Exhaust Air)
C
Isolation Relay Coil (Fresh Air)
C
Isolation Relay Coil (Exhaust Air)
Connect Terminals 4 & 5
Connect Switch between Terminals 1 & 4
Connect Terminals 4 & 5
Connect Terminals 4 & 5
Connect Terminals 2 & 3
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
MPU
Connect Terminals 2 & 3
Connect Switch between Terminals 1 & 4
UNIT INTERNAL CONTROL WIRING
(SIMPLIFIED)
A SWITCH OR NON-POWERED
CONTROL USING UNIT'S 24VAC POWER
SUPPLY
UNIT INTERNAL CONTROL WIRING
(SIMPLIFIED)
24VAC FROM AN EXTERNAL SOURCE
Unit's 24VAC
Power Supply
UNIT INTERNAL CONTROL WIRING
(SIMPLIFIED)
AN EXTERNAL CONTROL USING UNIT'S
24VAC POWER SUPPLY
24VAC Available at Terminals 1 & 2
Unit's 24VAC
Power Supply
Unit's 24VAC
Power Supply
Connect Terminals 2 & 3
UNIT INTERNAL CONTROL WIRING
C
Isolation Relay Coil (Fresh Air)
(SIMPLIFIED)
A SWITCH OR NON-POWERED
CONTROL USING UNIT'S 24VAC POWER
SUPPLY
Unit's 24VAC
Power Supply
C
Isolation Relay Coil (Exhaust Air)
UNIT INTERNAL CONTROL WIRING
C
Isolation Relay Coil (Fresh Air)
(SIMPLIFIED)
TWO EXTERNAL RELAY CONTACTS
SUPPLYING 24VAC FROM AN
EXTERNAL SOURCE
Unit's 24VAC
Power Supply
C
Isolation Relay Coil (Exhaust Air)
C
Isolation Relay Coil (Fresh Air)
C
Isolation Relay Coil (Exhaust Air)
C
Isolation Relay Coil (Fresh Air)
C
Isolation Relay Coil (Exhaust Air)
C
Isolation Relay Coil (Fresh Air)
C
Isolation Relay Coil (Exhaust Air)
Connect Terminals 4 & 5
Connect Switch between Terminals 1 & 4
Connect Terminals 4 & 5
Connect Terminals 4 & 5
Connect Terminals 2 & 3
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
