CT30 Series • Owner's Manual
Label wires and remove old wallplate
Use a screwdriver to disconnect wires one by one. As you disconnect each wire, wrap it with
the label matching the letter on your old thermostat. (Adhesive labels are supplied in your
Remove the old wallplate only after all wires are labeled. Be careful not to let loose wires fall
into the wall opening.
Wrap supplied labels securely around each wire. Do not let wires fall into wall opening!
For CT30/CT33: If your old
thermostat has 3 or more wires
(not counting terminals C or C1),
you may have purchased the
wrong replacement thermostat.
Stop now and call 1-800-468-1502
Mark mounting position
IGNORE WIRE COLORS: Use only letter
designations to identify wire types.
1. Pull wires
2. Level base if
3. Mark positions
of both screw
For CT31: If your old thermostat
has 5 or more wires (not counting
terminals C or C1), you may have
purchased the wrong replacement
thermostat. Stop now and call
1-800-468-1502 for advice.