Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Catalog No. 02-DFC535SI
Printed in U.S.A.
Form 53-5SI
Pg 1
11-05
Replaces: 53-2SI
Book 1
4
Tab
3e 2f
MULTI-STAGE • SEVEN DAY PROGRAMMABLE
STEP #1 PREPARATION
1
STEP #2 WIRE CONNECTIONS
1
SAMPLE WIRING DIAGRAMS
2
STEP #3 TEST OPERATION
2
ADVANCED SETUP
2
ABOUT ADVANCED FEATURES
AND OPERATION
3
TROUBLESHOOTING
5
CALIBRATION
5
This device complies with Part 15 of the FCC rules. Op-
eration 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
interference that may cause undesired operation.
Refer to the chart below, or the wiring diagrams that
follow for thermostat functions and corresponding ther-
mostat connectors.
*Only used with Heat Pump systems.
Table of Contents
IMPORTANT:
Follow
Installation Instructions
carefully.
CAUTION:
DISCONNECT POWER TO THE SYS-
TEM BEFORE INSTALLING THE NEW THERMOSTAT.
SERIOUS PERSONAL INJURY MAY RESULT.
STEP #1
PREPARATION
A.
Proper installation of the thermostat will be accom-
plished by following these step by step instructions.
If you are unsure about any of these steps, call a
qualified technician for assistance.
B.
Assemble tools:
C.
Carefully unpack the thermostat. Save the screws,
bracket, and instructions.
D.
Turn off the power to the system at the main fuse
panel. Most systems have a separate breaker for
disconnecting power to the indoor and outdoor
units.
STEP #2
WIRE CONNECTIONS
FUNCTION
INSTALL ON THE
NEW THERMOSTAT
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
Defrost
H1
Flat Blade
Screwdriver
Wire Cutter
and Stripper
Installation Instructions
DIGITAL THERMOSTAT 53DFS250-SL
Cooling Only, Heat Cool, and Heat Pump
AUTO
o
o
COOL
HEAT
!
