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Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Catalog No. 02-DFC534SI
Printed in U.S.A.
Form 53-4SI
Pg 1
11-05
Replaces: 53-1SI
Book 1
4
Tab
3e 2f
PROGRAMMABLE
STEP #1 PREPARATION
1
STEP #2 WIRE CONNECTIONS
1
SAMPLE WIRING DIAGRAM
2
STEP #3 TEST OPERATION
2
ADVANCED SETUP
2
ABOUT ADVANCED FEATURES
AND OPERATION
3
TROUBLESHOOTING
4
CALIBRATION
4
This device complies with Part 15 of the FCC rules. Opera-
tion is subject to the following 2 conditions: (1) This device
may not cause harmful interference, and (2) This device
must accept any interference received, including interfer-
ence that may cause undesired operation.
Refer to the chart below, or the wiring diagram that
follows.
*Not applicable for use with Duct-Free Splits heat pump systems.
Table of Contents
IMPORTANT:
Follow
Installation Instructions
carefully.
CAUTION:
DISCONNECT POWER TO THE SYS-
TEM BEFORE REMOVING THE OLD THERMOSTAT
AND INSTALLING THE NEW THERMOSTAT. SERIOUS
PERSONAL INJURY COULD RESULT.
STEP #1
PREPARATION
A.
Proper installation of the thermostat will be ac-
complished by following these step by step in-
structions. If you are unsure about any of these
steps, call a qualified technician for assistance.
B.
Assemble tools and recommended junction box.
For best operation, install the thermostat in a junc-
tion box that is free from drafts that originate in-
side the wall.
C.
Carefully unpack the thermostat. Save the screws,
bracket, and instructions.
D.
Power to the system should be off for installation
or replacement.
STEP #2
WIRE CONNECTIONS
FUNCTION
INSTALL ON THE
CONNECTOR MARKED
Lo Fan
G1
Compressor
Y
Heating
H2
24 v Power
R
Common
C
Rev. Valve
O*
Hi Fan
G2
Remote 5vdc
RS+5
Remote Sensor Signal
RS
Remote Sensor Ground
RS GND
Dry Contact Switch 1
CK1
Dry Contact Switch 2
CK2
Flat Blade
Screwdriver
Wire Cutter
and Stripper
.366”
WA
L
L
WA
LL
FLATSTAT
EXTENDS
LESS THAN
3/8" FROM
THE WALL.
Flatstat
in Small
J-Box
Installation Instructions
DIGITAL THERMOSTAT 53DFS250-FS
Heat Cool and Cooling Only
H
EAT
AUTO
COOL
!