Installation Instructions for
Heating & Air Conditioning
IF73
Non- Programmable, Auto Changeover
Multi-stage/Heat Pump Thermostat
CONTENTS
Preparations .................................................. 1
Thermostat Details ........................................ 1
Removing Old Thermostat ......................... 1-2
Mounting and Wiring .................................. 2-4
Check Thermostat Operation ..................... 5-6
Specifications ................................................ 6
Operation ...................................................... 6
Troubleshooting ......................................... 7-8
PREPARATIONS
THERMOSTAT DETAILS
REMOVING OLD THERMOSTAT
Before removing wires from old thermostat’s switching subbase,
label each wire with the terminal designation it was removed from.
1. Remove Old Thermostat: A standard heat/cool thermostat
consists of three basic parts:
a. The cover, which may be either a snap-on or hinge type.
b. The base, which is removed by loosening all captive screws.
c. The switching subbase, which is removed by unscrewing
the mounting screws that hold it on the wall or adaptor plate.
2. Shut off electricity at the main fuse box until installation is
complete. Ensure that electrical power is disconnected.
3. Remove the front cover of the old thermostat. With wires still
attached, remove wall plate from the wall. If the old thermostat
has a wall mounting plate, remove the thermostat and the wall
mounting plate as an assembly.
4. Identify each wire attached to the old thermostat.
5. Disconnect the wires from the old thermostat one at a time. DO
NOT LET WIRES FALL BACK INTO THE WALL.
6. Install new thermostat using the following procedures.
To prevent electrical shock and/or equipment damage,
disconnect electrical power to the system at the main
fuse or circuit breaker until installation is complete.
CAUTION
!
Printed in U.S.A.
PART NO. 37-6429A
0230
WHITE-RODGERS
EMERSON ELECTRIC CO.
9797 REAVIS ROAD
ST. LOUIS, MISSOURI 63123-5398
www.white-rodgers.com
Failure to follow and read all instructions carefully
before installing or operating this control could cause
personal injury and/or property damage.
Assemble tools required as shown below.
YOUR THERMOSTAT REPLACES
1
2
3
WIRE CUTTER/STRIPPER
HAND OR POWER
DRILL WITH 3/16 INCH
DRILL BIT, IF NEEDED
FLAT BLADE SCREWDRIVER
SPIRIT LEVEL OR PLUMB BOB AND LINE OPTIONAL—
THERMOSTAT DOES NOT NEED TO BE LEVEL TO WORK PROPERLY
Description
1F73
Heat Pump (No Aux or Emergency Heat)
Yes*
Heat Pump (with Aux or Emergency Heat)
Yes*
Standard Heat & Cooling Systems
Yes*
Two Stage Heat & Two Stage Cool
Yes*
Standard Heat Only Systems
Yes*
Millivolt Heat Only Systems – Floor or Wall Furnaces
No
Standard Central Air Conditioning
Yes*
Gas or Oil Heat
Yes*
Electric Furnace
Yes*
Hydronic (Hot Water) Zone Heat – 2 Wires
Yes*
Hydronic (Hot Water) Zone Heat – 3 Wires
No
* Requires common for 24 VAC at the thermostat
(O/B)Y2
E/W1
R
C
Y1
W2
G
GAS
ELEC
B
O
L
Figure 1. Thermostat Base
Elec – Gas
Switch
Mounting
Hole
Mounting
Hole
O/B Terminal
Switches Selection
