Honeywell CT87A - Manual (Page 2)

CT87A,B,J ROUND® THERMOSTAT
69-0274-6 2
Prepare for installation
1. Carefully unpack your new thermostat; rough handling may affect its
accuracy. Save your receipt and identify the following parts:
• CT87 Thermostat
• Screws: two 1-in. sheet metal screws, two 1/2-in. binding head
screws, and two 1/4-in. round head screws
• Wallplate (CT87A) or subbase (CT87B, CT87J)
• Cover ring (select models only). Necessary if installing on an
outlet box. Optional if installing directly on the wall; can be used to
hide wall marks.
• These Installation Instructions and the Installation Quick Guide.
• Wiring labels
2. Gather these tools:
Remove the old thermostat
1. Turn off power to the heating/cooling system at the main fuse/circuit
breaker panel.
2. Remove the cover of your old thermostat. You may need to unscrew
the cover if it is locked on.
3. Locate the heat anticipator adjustment scale and lever on the old
thermostat (Fig. 1).
In the box below, record the
number that the adjustment lever
points to. This is the current (amp)
rating of your heating system.
Current setting:
If you cannot find the heat
anticipator setting on the old
thermostat, you can use a
standard setting for your type of
system when you reach Step 8 of
this installation.
4. Unscrew and remove the old thermostat wallplate from the wall, but
do not disconnect the wires.
Required Tools Optional Tools
• Flat blade
screwdriver
• Spirit level
• Hand or power drill with 1/16-in. drill bit
• Wire cutter/stripper or sharp knife
• Pencil
2
3
M20206
MERCURY
SWITCH
OLD THERMOSTAT
ANTICIPATOR
SCALE
LEVER
TYPICAL LOCATION OF A
MERCURY SWITCH IN
A THERMOSTAT
Fig. 1. Mercury switch location.