CT50 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
thermostat package.)
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 CT50/CT53/CT54: 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 for advice.
Mark mounting position
CT50/CT53/CT54
69-2040EFS—04
CT50/CT53/CT54
M23787
IGNORE WIRE COLORS: Use only letter
designations to identify wire types.
1. Pull wires
2. Level base if
3. Mark positions
M23789
through base.
desired.
of both screw
holes.
2
CT51/CT55
M23788
For CT51/CT55: If your old
thermostat has 7 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.
CT51/CT55
M23790