CONTENTS
Preparations ...........................................
Thermostat Features ..............................
Removing Old Thermostat .....................
Mounting and Wiring ..............................
New Thermostat Operation ....................
Specifications .........................................
Troubleshooting .....................................
1
2
3
4
5
6
7
Installation Instructions for
Cooling only
1C21
PREPARATIONS
YOUR THERMOSTAT REPLACES
1
Assemble tools required as shown below.
Description
1C21
Standard Heating & Cooling Systems - 4 or 5 wires
Standard Cool Only Systems
No
Yes
Yes
Yes
No
FLAT BLADE SCREWDRIVER
WIRE CUTTER/STRIPPER
Millivolt Cool Only Systems - Floor or Wall Furnaces
Standard Central Air Conditioning
HAND OR POWER
Gas or Oil Heat
DRILL WITH 3/16 INCH
DRILL BIT, IF NEEDED
Electric Furnace
No
Hydronic (Hot Water) Zone Heat - 2 Wires
Hydronic (Hot Water) Zone Heat - 3 Wires
Heat Pump (No Aux or Emergency Heat)
Heat Pump (with Aux or Emergency Heat)
Baseboard Electric Heating or Line Voltage (120 or 240 Volt)
No
SPIRIT LEVEL OR PLUMB BOB AND LINE OPTIONAL—
THERMOSTAT MUST BE LEVEL TO WORK PROPERLY
No
No
Failure to follow and read all instructions carefully be-
fore installing or operating this control could cause
personal injury and/or property damage
No
No
THERMOSTAT FEATURES
REMOVING OLDTHERMOSTAT
2
3
CAUTION
!
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.
MOUNTING SCREWS
CAPTIVE SCREWS
Before removing wires from old thermostat’s switching subbase,
label each wire with the terminal designation it was removed from.
Some models also include an adaptor plate to cover unpainted
surfaces. Thermostat wires pass through the adaptor plate center
opening.
1. Remove Old Thermostat: A standard heat/cool thermostat
BASE
consists of two 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.
ATTENTION! This product does not contain mercury. How-
ever, this product may replace a unit which contains mercury.
Do not open mercury cells. If a cell becomes damaged, do not
touch any spilled mercury. Wearing non-absorbent gloves, take
up the spilled mercury and place into a container which can be
sealed. If a cell becomes damaged, the unit should be discarded.
COVER
Adaptor Plate
(optional)
Figure 1.
Mercury must not be discarded in household trash. When the unit
this product is replacing is to be discarded, place in a suitable
container.Refertowww.white-rodger.comforlocationtosendthe
product containing mercury.
PART NO. 37-6370B
Replaces 37-6370A
0835