Step 3. Mount Thermostat Wallplate - Honeywell CT3500 Owner's Manual

Replacing a Thermostat that has Three Wires
If you have three wires for a heating only system and can operate the fan using the fan ON switch this thermostat
works with your system. However, some hot water (zoned) heating systems also have three wires. Your thermostat will
work only if you install an isolating relay on these systems. For details, call your local heating and/or cooling contractor.

STEP 3. MOUNT THERMOSTAT WALLPLATE

q
Separate the wallplate from the thermostat by placing your thumb or fingers between
the bottom of the wallplate and the thermostat, and pulling the wallplate up and away
from the thermostat. See illustration at right.
q
Position the wallplate on the wall. Level the wallplate for appearance if desired. Use a
pencil to mark the two mounting holes that best fit the application.
q
Remove the wallplate from the wall. Drill two 3/16 in. holes in wall
(if drywall) as shown. For materials such as plaster or wood, drill
7/32 in. holes where marked. Gently, tap the (provided) anchors
into the drilled holes until they are flush with the wall.
q
Reposition the wallplate over the holes. Pull the wires through the
wiring opening. Loosely insert mounting screws into each of the
holes.
q
Level the wallplate if desired. Thermostat functions properly when
not level.
q
Tighten mounting screws.
WALL
ANCHORS (2)
7
WALL
WIRES
THROUGH WALL
MOUNTING
SCREWS
69-1199—4
M16427
MOUNTING
HOLES
M15044