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E
2017 Lennox Industries Inc.
Dallas, Texas, USA
THIS MANUAL MUST BE LEFT WITH THE HOMEOWNER
FOR FUTURE REFERENCE
INSTALLATION
INSTRUCTIONS
ComfortSense
®
3000 Series
Models L3011C
/
L3021H
Non‐Programmable
Thermostats
CONTROLS
506080-02
5/2017
Supersedes 506080-01
Table of Contents
L3011C /L3021HThermostats
1
. . . . . . . . . . . . . . . . . . .
General
1
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Shipping & Packing
1
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Requirements
2
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation
2
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Thermostat Operation
3
. . . . . . . . . . . . . . . . . . . . . . . . . .
DIP Switch Settings
3
. . . . . . . . . . . . . . . . . . . . . . . . . . .
Wiring Diagrams
5
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
WARNING
This product contains a chemical known to the State of
California to cause cancer, birth defects, or other
reproductive harm.
WARNING
Improper installation, adjustment, alteration, service or
maintenance can cause personal injury, loss of life, or
damage to property.
Installation and service must be performed by a licensed
professional installer (or equivalent) or a service agency.
L3011C/L3021H Thermostats
These are non‐programmable electronic thermostats
which are easy‐to‐use, have a large, easy‐to‐read display,
and provide excellent temperature control. Both thermo
stat models also includes a programmable filter change re
minder, and a system check indicator which will notify the
user of the need for equipment service.
Thermostat model L3011C is suitable for non‐heat pump,
single-stage heat/single-stage cool applications that are
matched with a gas or electric furnace.
Thermostat model L3021H is suitable for single-stage heat
pump applications that are matched with a gas or electric
furnace as the auxiliary heat source. An optional outdoor
temperature sensor provides auxiliary heat lockout/bal
ance point operation and dual-fuel compatibility.
General
These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
having jurisdiction before installation.
Check equipment for shipping damage. If you find any
damage, immediately contact the last carrier.
Shipping and Packing List
1 - Thermostat (L3011C or L3021H)
2 - Plastic wall anchors
2 - Screws
Optional Accessories
Outdoor Sensor (used with L3021H only): X2658
Wall Plate: X2659