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© COPYRIGHT 2004 LUX PRODUCTS CORPORATION. ALL RIGHTS RESERVED
• The TX250 can be
used with most 24
volt gas, oil or
electric heating
and air
conditioning
systems, single-
stage heat pumps
or gas millivolt
heating systems.
It cannot be used
with 120 volt heating
systems or multistage
heat pumps. Ask your
dealer for other LUX
thermostats to
control those
systems.
• The TX250 is
programmable.
There are four
programming periods
per day. Each period can be programmed separately.
•
Easy to use Speed Slide.
• You can use the built-in time/temperature programs, or alter them to suit your
schedule.
The TX250 provides separate programming for weekdays and weekends
— for both heating and cooling. You can override the programmed temperatures for
as little as one programming period or for an entire vacation.
• In cool weather,
when the system switch is set to HEAT, the TX250 may maintain
cooler “set back” room temperatures to save energy. It will then change to warmer
“comfort” settings — automatically, at specified times during the day.
• In warm weather,
when the system switch is set to COOL, the TX250 may maintain
warmer “set back” room temperatures to save energy. It will then change to cooler
“comfort” settings — automatically, at specified times during the day.
• A liquid crystal display
shows time, day of the week, and room and set
temperatures.
• Temperature swing adjustment
lets you fine-tune your system for maximum
comfort and economy.
• A 2 or 5-minute minimum off time
in COOL prevents your air conditioning system
from being damaged.
• Two
Energizer
®
or DURACELL
®
“AA” alkaline batteries
(not included) are used to
retain your time and temperature programs.
LUX PRODUCTS CORPORATION • Mt. Laurel, New Jersey 08054, USA
43374
FEATURES
I M P O R T A N T !
Thank you for your confidence in our product. To obtain the best results
from your investment, please read these instructions and acquaint yourself with
your purchase before installing your new thermostat. Then follow the
installation procedures, one step at a time. This will save you time and
minimize the chance of damaging the thermostat and the systems it controls.
These instructions may contain information beyond that required for your particular installation.
Please save for future reference.
READ
INSTALLATION
INSTRUCTIONS
FIRST
TX250 SERIES
SMART TEMP
ELECTRONIC THERMOSTAT
Complete, Easy To Read Programming And Installation Instructions Inside
Liquid Crystal
Display
Fan Switch
Thermostat
Body
HEAT
OFF
COOL
MO
Choose Heat or Cool
Set Day & Time
Installs Easily
Easy as
1–2–3
INSTALLATION AND OPERATING INSTRUCTIONS
Separator
Tabs
Speed
Slide
Reset
Button
Mode
Switch
WARNING:
Use Energizer
®
or DURACELL
®
Alkaline Batteries Only.
Energizer
®
is a registered trademark of Eveready Battery Company, Inc.
DURACELL
®
is a registered trademark of The Gillette Company, Inc.
INSTALLATION
Please read all instructions carefully
before beginning installation.
TOOLS REQUIRED
#1 Phillips screwdriver (small)
Drill with 3/16-in. (4.8mm) bit
THERMOSTAT LOCATION
On replacement installations, mount the new thermostat in place of the old one
unless the conditions listed below suggest otherwise. On new installations, follow
the guidelines listed below.
1. Locate the thermostat on an inside wall, about 5 ft. (1.5m) above the floor, and in
a room that is used often.
2. Do not install it where there are unusual heating conditions, such as: in direct
sunlight; near a lamp, radio, television, radiator, register, or fireplace; near hot
water pipes in a wall; near a stove on the other side of a wall.
3. Do not locate in unusual cooling conditions, such as: on a wall separating an
unheated room; or in a draft from a stairwell, door, or window.
4. Do not locate in a damp area. This can lead to corrosion that will shorten
thermostat life.
5. Do not locate where air circulation is poor, such as: in a corner or an alcove; or
behind an open door.
6. Do not install the unit until all construction work and painting has been completed.
7. This thermostat does not require leveling.
C A U T I O N
To avoid electrical shock and
to prevent damage to the
furnace, air conditioner, and
thermostat, disconnect the power
supply before beginning work. This
can be done at the fuse box, at the
circuit breaker, or at the appliance.
OFF
REMOVING THE OLD THERMOSTAT
Switch electricity to the furnace and air conditioner
OFF; then proceed with the following steps.
2. Note the letters printed near the terminals. Attach
labels (enclosed) to each wire for identification.
Remove and label wires one at a time. Make sure the
wires do not fall back inside the wall.
3. Loosen all screws on the old thermostat and remove it from the wall.
MOUNTING THE TX250 ON THE WALL
3. Cup and hold thermostat body and left tab in place with left hand. Separarte tabs
with right hand.
C A U T I O N
Read instructions carefully
before removing any
wiring from existing
thermostat. Wires must be
labeled before they are
removed. When removing
wires from their terminals,
ignore the color of the
wires since these may not
comply with the standard.
Y
W
1. Remove cover from old thermostat.
Most are snap-on types and simply
pull off. Some have locking screws
on the side. These must be loosened.
C
A
U
T
I
O
N
Be careful not to drop the body or disturb electronic parts.
Y
W
R
2. Fill wall opening with
non-combustible
insulation to prevent
drafts from affecting
the thermostat.
Y
W
1. Strip insulation 3/8 in.
(9.5mm) from wire ends
and clean off any corrosion.
C
A
U
T
I
O
N
• Your thermostat is a precision instrument. Please handle it with care.
• Turn off electricity to the appliance before installing or servicing thermostat or any
part of the system. Do not turn electricity back on until work is completed.
• Do not short (jumper) across electric terminals at control on furnace or air
conditioner to test the system. This will damage the thermostat and void your
warranty.
• All wiring must conform to local codes and ordinances.
• This thermostat is designed for use with 24 volt and millivolt systems. The
thermostat should be limited to a maximum of 1.0 amps; higher amperage may
cause damage to the thermostat. If you are in doubt, call your utility company.
