08/07
505,048M
*2P0807*
*P505048M*
E
2007 Lennox Industries Inc.
Dallas, Texas, USA
RETAIN THESE INSTRUCTIONS
FOR FUTURE REFERENCE
51M34 5/2 Day Programmable Thermostat
The Lennox 51M34 5/2 day programmable electronic
thermostat has a large, easy-to-read display and provides
excellent temperature control. This product includes a
programmable filter change reminder, an equipment
maintenance reminder, and a system check indicator to
notify the user when the equipment requires service.
The 51M34 thermostat is suitable for non−heat pump,
single-stage heat/single-stage cool applications with either
gas or electric furnace.
OPERATION
MANUAL
51M34
5/2 Day
Programmable Thermostat
CONTROLS
505,048M
08/07
Supersedes 05/05
Table of Contents
51M34 5/2 Day Programmable Thermostat
1
. . . . . . .
General
1
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Introduction
1
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Initial Thermostat Power-up
1
. . . . . . . . . . . . . . . . . . . . .
Buttons, Backlight, Timers & Settings
2
. . . . . . . . . . . .
DAY/TIME − Set Day and Time
2
. . . . . . . . . . . . . . . . . .
HEAT − Heat Mode
3
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
COOL − Cool Mode
3
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
HOLD − Temperature Hold Mode
4
. . . . . . . . . . . . . . . .
PROG − Thermostat Programming
4
. . . . . . . . . . . . . . .
FAN − Controlling Fan Operation
5
. . . . . . . . . . . . . . . . .
SETTINGS − Filter /Maintenance Reminder
5
. . . . . . .
Service Indicator
6
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Thermostat RESET
6
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removing/Installing Thermostat
6
. . . . . . . . . . . . . . . . .
Default Thermostat Settings
6
. . . . . . . . . . . . . . . . . . . .
Technical Specifications
7
. . . . . . . . . . . . . . . . . . . . . . . .
Thermostat Output Table
8
. . . . . . . . . . . . . . . . . . . . . . .
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.
Introduction
This document describes the operation of Lennox 51M34
thermostat . Refer to the installation manual for instructions
regarding installation and wiring of the thermostat.
Initial Thermostat Power-up
When power is initially applied to the thermostat, the dis-
play will appear as shown in figure 1.
FAN
ON
AUTO
SYSTEM
COOL
OFF
EMG.
HEAT
I8:88
88
AM
PM
ROOM
88
MO TU WE TH FR SA SU
SETPOINT
°
°
SERVICE
FILTER
MAINT
Hi
Lo
PROG
A | B | C | D
HOLD
Figure 1. Initial Power−Up Display
All display segments are momentarily activated. This oc-
curs as a normal part of thermostat initialization. Within a
few seconds, the Home Screen appears (see figure 2) with
default settings as shown. After about 1 minute of initializa-
tion time, the actual room temperature will be displayed.
Litho U.S.A.
