X-XX UL
INSTALLATION INSTRUCTIONS
®U.S. Registered Trademark
Copyright © 1998 Honeywell Inc. • • All Rights Reserved
T8112C,D Electronic Programmable Thermostats

APPLICATION

The T8112C,D thermostats provide electronic
programmable control for 24 to 30 Vac heating and
cooling systems.

RECYCLING NOTICE

If this control is replacing a control that contains
mercury in a sealed tube, do
not
place your old
control in the trash.
Contact your local waste management authority
for instructions regarding recycling and the proper
disposal of the old thermostat.

INSTALLATION

When Installing this Product…
1. Read these instructions carefully. Failure to follow
them could cause a hazardous condition.
2. Check the ratings given in the instructions and on
the product to make sure the product is suitable for
your application.
3. Installer must be a trained experienced service
technician.
4. After installation is complete, check out product
operation as provided in these instructions.

CAUTION

1. Disconnect power supply to prevent electrical
shock or equipment damage.
2. After wiring is complete, push excess wire
back into the hole and plug hole with
nonhardening caulk, putty or insulation to
prevent drafts from affecting thermostat
operation.
Location
Install the thermostat about 5 ft. (1.5m) above the floor in
an area with good air circulation at average temperature.
Do not install the thermostat where it can be affected by:
—drafts, or dead spots behind doors and in corners.
—hot or cold air from ducts.
—radiant heat from sun or appliances.
—concealed pipes and chimneys.
—unheated (uncooled) areas such as an outside wall
behind the thermostat.
Mounting Plate Installation
Position mounting plate on the wall. Use a level to make
sure mounting plate is level. Use a pencil to mark the two
mounting holes. See Fig. 1.
WALL
WIRES THROUGH
WALL OPENING
WALL ANCHORS (2)
MOUNTING
PLATE
MOUNTING
SCREWS (2)
M1718
69-0917-2
Fig. 1. Mounting plate installation.