Lennox iComfort M30 Assembly instructions

507739-01
10/2017
Supersedes 9/2017
iComfort®M30 Smart Thermostat
Installation and Setup Guide
Disponible en español en www.LennoxPros.com.

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Tables of Contents
Shipping and Packing List........................... 3
Thermostat.................................................... 3
Wall Plate Dimensions (H x W) ............................... 3
Compressor Short-Cycle Protection
(Compressor Protect).............................................. 3
Installation Considerations ......................... 4
Outdoor Temperature Sensor Installation
(Optional)....................................................... 5
Thermostat Installation ............................... 5
New Installation....................................................... 5
Replacement Installation......................................... 6
Common Installation Practices................................ 6
Thermostat Terminal Information ............................ 8
System Wiring Diagrams......................................... 9
Connecting Thermostat Wiring................................ 9
Supported Congurations ....................................... 9
Install Thermostat to Backplate............................. 12
Commissioning and Advanced Settings.. 12
Commissioning...................................................... 12
Advanced Settings ................................................ 15
Advanced Settings Parameter Descriptions.......... 18
Stage Control.............................................. 22
Wi-Fi Connection ........................................ 27
Connecting to Visible Home Wi-Fi Access Point... 28
Connecting to Hidden Home Wi-Fi Access Point .. 28
Wireless Terminology ............................................ 29
Wireless Connectivity Troubleshooting Tips ... 29
Determining Wireless Connection Signal
Strength................................................................. 29
Alert Codes ................................................. 30
System Test Modes .................................... 33
Save Energy Default................................... 33
Dehumidication Control........................... 34
Normal and Max.................................................... 34
Humiditrol ............................................................. 35
Auxiliary Dehumidier ........................................... 36
Humidication Control............................... 36
Normal and Max.................................................... 37
Normal and Max Dew Point Control...................... 37
Installer Checklist....................................... 39
Index ............................................................ 40

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WARNING
This product contains a chemical known to the
State of California to cause cancer, birth defects,
or other reproductive harm.
Shipping and Packing List
Item Quantity
M30 Thermostat with backplate attached 1
Wall plate 1
Mounting screws (M3.5x25mm self-tapping screws) 2
Wall anchors 2
Warranty sheet 1
Installation & setup guide 1
User guide 1
System Wiring Diagrams Fold-Out Sheet 1
Thermostat
Unit Dimensions (H xW xD)
Dimensions: 3-5/16 x 4-5/16 x 7/8 in. (84 x 110 x
22mm)
Wall Plate Dimensions (H xW)
Dimensions: 4-1/2” x 5-3/4” (114 x 146mm)
ComPressor sHort-CyCle ProteCtion
(ComPressor ProteCt)
This thermostat is equipped with automatic
compressor protection to prevent potential damage
due to short cycling or extended power outages.
The non-adjustable short-cycle protection provides
a 5-minute delay between heating or cooling cycles
to prevent the compressor from being damaged.
NOTE: There is an option in advanced settings that
will allow this safety feature to be disabled.
By default it is set to ON. Short Cycle
protection is disabled during testing of the
outdoor unit. It is automatically reset once
the test is completed.
WARNING
Improper installation, adjustment, alteration, ser-
vice or maintenance can cause property damage,
personal injury or loss of life.
Installation and service must be performed
by a licensed professional HVAC installer (or
equivalent) or a service agency.

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IMPORTANT
In all applications, the M30 thermostat can only
be used with all residential units and approved
commercial split-system matches, and those
which meet the following installation criteria:
Installation uses 18 gauge thermostat wire or
larger and wire run length DOES NOT EXCEED
300 feet (91 meters).
Load from any thermostat connection is 1 AMP
or less.
WARNING
Always turn off power at the main power source by
switching the circuit breaker to the OFF position
before installing or removing this thermostat.
All wiring must conform to local and national
building and electrical codes and ordinances.
CAUTION
This is a 24VAC low-voltage thermostat. Do not
install on voltages higher than 30VAC.
Do not short (jumper) across terminals on the gas
valve or at the system control to test installation.
This will damage the thermostat and void the
warranty.
Installation Considerations
Before beginning installation, note the type of
equipment, number of stages, and any accessories
being installed. This thermostat is a 24VAC low-
voltage thermostat and requires a common wire to
the thermostat to operate.
• Shut off all power to system components before
installing thermostat.
• Make sure that all wiring conforms to local
and national building and electrical codes and
ordinances.
• Never short (jumper) across terminals on the gas
valve or at the system control to test installation.
This will damage the thermostat and void the
warranty.
• Never install thermostat on outside walls or in
direct sunlight.

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Outdoor Temperature Sensor
Installation (Optional)
Install the optional (purchase separately) outdoor
sensor (X2658) on a northern wall of the home,
away from direct sunlight or other heat sources that
may affect its sensitivity.
The sensor is required for:
• Outdoor temperature displays on the home
screen if enabled
• Balance point adjustment and control. The sensor
enables optimal heating equipment operation via
programmable balance points.
• Dew point humidity control
• Humiditrol EDA operation (required)
• Requires 22AWG thermostat wire or larger and
not to exceed 300 feet (91 meters) maximum run.
• Connects to To and Tc terminals on thermostat
Connect outdoor sensor to terminals Tc and To on
thermostat.
NOTE: If alert code 108 appears on the screen,
check your wiring connections to terminals
To and Tc on the thermostat. Check
resistances using the resistance table
provided in the outdoor sensor instruction.
Thermostat Installation
neW installation
The following procedure is for new installation or
installing the M30 to a new location in an existing
home.
1. Unpacked the thermostat and open the case
with a thin-blade screwdriver. Place between
wall base and unit and twist to separate unit
from base.
2. Select a location for the thermostat about 5
feet (1.5 meters) above the oor in an area with
good air circulation at average temperature.
3. Do not install the thermostat where it can be
affected by:
• Drafts or dead spots behind doors and in
corners.
• Building entrances or automatic doors
• Heat generating equipment such as kitchen
equipment
• Enclose environment unless a remote indoor
sensor is used.
• Hot or cold air from ducts.
• Radiant heat from sun or appliances.
• Concealed pipes and chimneys.
• Non-heated (non-cooled) areas such as an
outside wall behind the thermostat.

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4. Run thermostat wiring from indoor unit to
location where thermostat will be installed.
5. Drill or make opening through wall for thermostat
wiring 3/4” x 3/4” (19mm x 19mm).
6. Pull about 3 inches (76mm) of thermostat
wire through the opening and removed outer
thermostat wire jacket. This will help in routing
the thermostat wiring to the proper thermostat
terminals.
NOTE: Thermostat wires and outdoor sensor wire
can be run in the same bundle of wires if
needed.
7. Seal the hole in the wall with a suitable material
to prevent drafts from entering the thermostat
case. Not doing so could affect the thermostat’s
internal temperature sensor.
8. Trim 1/4 inch (6 mm) insulation from end of
each thermostat wire lead.
1/4”
rePlaCement installation
Use the following two steps to replace an existing
thermostat.
1. Remove existing thermostat.
2. Note the wire colors and what terminals they are
connected for future reference.
Common installation PraCtiCes
1. Use the provided wall plate as a template on
where to drill the mounting holes.
NOTE: Installation of wall plate is optional. Use
a eld-provided level to allow for proper
alignment.
(Use a level) Align Wall Plate
Use unit wall plate as template to mark desired
mounting nhole locations on wall.

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2. Drill 3/16” (5 mm) holes in wall for provided
wall anchors. Insert provided wall anchors into
drilled holes.
3. Remove back plate from main thermostat
assembly using a at-head screw driver.
4. Route thermostat and outdoor temperature
sensor (optional) wiring from wall through
center openings on wall plate (use is optional)
and back plate.
Wall Plate (optional)
Thermostat
Back Plate
Run thermostat wire
through openings
5. Secure back plate and wall plate (optional) to
wall with the two provided mounting screws.
Wall Plate (optional)
Thermostat
Back Plate
Screw

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tHermostat terminal information
Table 1. Terminal Designations
Terminal Purpose
Tc and To Used for connection to an optional outdoor tempera-
ture sensor.
ACC1 and
ACC2
Default factory software setting for ACC (Accessory)
is off.
Terminal function setting can be changed by going to
settings > advanced settings > terminal settings.
Available settings are off, humidify and dehumidify.
Connect accessory to terminal ACC2 and change
software setting to the applicable type of accessory.
Power is supplied by R2 to ACC1 factory jumper.
NOTE: Do not remove the factory installed
jumper between ACC1 and R2 terminals
unless a secondary 24VAC power
source is connected to ACC1.
R2
This is the secondary 24VAC power source for ACC
(Accessory). The R2 terminal is connected to the
ACC1 terminal by factory provided jumper.
D/H
This terminal is for an optional dehumidier or hu-
midier.
Factory default software setting is for dehumidify.
Terminal settings can be changed by going to set-
tings > advanced settings > terminal settings.
Available settings are off, humidify and dehumidi-
fy.
NOTE: The user interface refers to the terminal
as H/D.
W2 Second-stage heating (non-heat pump) or 4th stage
(heat pump).
Y2 Second-stage heating or cooling.
Table 1. Terminal Designations
Terminal Purpose
O/B
Heat pump reversing valve operations. When O (de-
fault) is selected under settings > advanced set-
tings > terminal settings, the relay is ON during
cooling and OFF during heating.
When B is selected, the relay is ON during heating
and OFF during cooling.
CCommon 24VAC
GFan relay
W1 First-stage heating (non-heat pump or emergency
heat) or third-stage heating (heat pump)
Y1 First-stage heating or cooling
R24VAC power
Table 2. O/B Terminal Relationship States
State O/B Terminal Control
Power ON O terminal : ON (If O terminal selected)
B terminal : OFF (If B terminal selected
Heat only or
emergency
heat mode
O terminal : always OFF
B terminal : always ON
Cool mode
only
O terminal : always ON
B terminal : always OFF

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Table 2. O/B Terminal Relationship States
State O/B Terminal Control
Heat/Cool
mode
During heating
O terminal : OFF
B terminal : ON
During cooling
O terminal : ON
B terminal : OFF
No Demand
The terminal continues the previous ON / OFF
state
Off mode The terminal state continues the state before en-
tering off mode
system Wiring Diagrams
For system diagrams, see the included fold-out
iComfort® M30 Smart Thermostat System
Diagrams sheet.
ConneCting tHermostat Wiring
Use “Table 1. Terminal Designations” on page 8
for connecting the thermostat wiring to the back
plate terminals.
If this is a replacement thermostat, connect
to terminals as noted when removing the old
thermostat. If terminals were different on old
thermostat, use “Table 1. Terminal Designations” on
page 8 and wiring diagrams provided in the kit.
NOTE: Remember to seal the hole in the wall with
a suitable material to prevent drafts from
entering the thermostat case. Not doing
so could affect the thermostat’s internal
temperature sensor.
sUPPorteD ConfigUrations
See “Table 3. Supported Congurations” on page
10.

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Table 3. Supported Congurations
Outdoor unit setting Indoor unit setting Comp. Stages Indoor Heat Stages Heat Stages Cool Stages
Heat Stage EM Heat Stage Cool Stage
1st 2nd 3rd 4th 1st 2nd 1st 2nd
HP
No Heat 1 0 1 1 Y1 - - - - - Y1 -
2 0 2 2 Y1 Y1+Y2 - - - - Y1 Y1+Y2
Gas / Oil
1 1 2 1 Y1 W1 - - W1 - Y1 -
1 2 3 1 Y1 W1 W1+W2 - W1 W1+W2 Y1 -
2 1 3 2 Y1 Y1+Y2 W1 - W1 - Y1 Y1+Y2
2 2 4 2 Y1 Y1+Y2 W1 W1+ W2 W1 W1+W2 Y1 Y1+Y2
Elec
1 1 2 1 Y1 Y1+W1 - - W1 - Y1 -
1 2 3 1 Y1 Y1+W1 Y1+W1+W2 - W1 W1+W2 Y1 -
2 1 3 2 Y1 Y1+Y2 Y1+Y2+W1 - W1 - Y1 Y1+Y2
2 2 4 2 Y1 Y1+Y2 Y1+Y2+W1 Y1+Y2+W1 +W2 W1 W1+W2 Y1 Y1+Y2