Lennox 19V30 Installation And Setup Guide

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Table 4. Communication Error Troubleshooting
(HD Display to smart hub)
Possible Connection Issues S30 smart hub - System Status LED
One communication wire at the smart hub COMM BUS A or B terminals is disconnected. Flashing Magenta LED
Both communication wires – at the smart hub COMM BUS A or B terminals are reversed. Flashing Magenta LED
Power wires at smart hub 12VDC + and - terminals are disconnected. Flashing Magenta LED.
If terminals are connected correctly, then check HD Display to subbase attachment. Verify the
display is securely fasten to subbase and horizontally aligned.
Flashing Magenta LED.
HD Display screen may be either blank or a message indicating iComfort cannot
communicate with the equipment.
Terminals and Wiring Recommendations
Table 5. Terminal Designations and Wiring Recommendations
Terminal
Designation
Description
Thermostat
Wiring
Typical Wiring
R 24VAC input
18AWG unshielded
Indoor Unit Controller
Outdoor Unit
Smart Hub
R i+ I- C
ACC1 ACC2
18 or 22AWG
shielded
18AWG
unshielded
18 or 22AWG
shielded
18 or 22AWG
shielded
18AWG
unshielded
-12V+12V A B
HD Display
Subbase
+
-
COMMBUS
A B
18 AWG
Unshielded
Shield wire needs to be
connected to a common (C)
terminal.
Connect shield wire
to indoor unit common
terminal only
C 24VAC return
I+ RS-BUS I+
18 - 22AWG shielded
(recommended)
I- RS-BUS I-
ACC1 Accessory 1 and
2 (typically can be
used for 1 or 2 speed
ventilators and fresh
air damper)
18AWG unshielded
ACC2
+ 12VDC output
18AWG unshielded
- 12VDC return
A
Communications
bus A
18 - 22AWG shielded
(recommended)
B
Communications
bus B
IMPORTANT
Use 1-pair, 18AWG unshielded thermostat cable (eld-provided) for power terminals (R, C, 12+ AND 12-). We highly recommend using 18 - 22AWG shielded
thermostat cable for communications terminals (I+, I-, A and B) which will help eliminate any noise interference.

Lennox 19V30 Specifications

General

Brand	Lennox
Model	19V30
Category	Thermostat
Language	English