Honeywell T834C Manual

T834C Heating-Cooling Thermostats
The T834 Heating-Cooling Thermostats provide 24 to
30 Vac control in heating-cooling systems. An spdt mer-
cury switch makes R to W on a temperature fall for heating,
and R to Y on a temperature rise for cooling. Integral
switches control HEAT-OFF-COOL system operation and
AUTO-ON fan operation. See Fig. 1.
Fig. 1—Internal view of T834C.
FAN
SWITCH
1
1 FAN SWITCH AVAILABLE ON T834C ONLY.
M3375
This control contains mercury in a sealed tube. Do not
place control in the trash at the end of its useful life.
If this control is replacing a control that contains mer-
cury 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
this control, or of an old control containing mercury in a
sealed tube.
WHEN INSTALLING THIS PRODUCT...
1. Read these instructions carefully. Failure to follow
them could damage the product or cause a hazardous condi-
tion.
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 tech-
nician.
4. After installation is complete, check out product
operation as provided in these instructions.
J.H. • Rev. 3-93 •
Application
MOUNTING HOLE
(THERMOSTAT
TO WALL OR
OUTLET BOX)
BIMETAL ELEMENT
BEHIND SCALE
ADJUSTABLE HEAT
ANTICIPATOR
INDICATOR
SYSTEM
SWITCH
MOUNTING HOLE
TEMPERATURE
SETTING LEVER
M8676
Recycling Notice
Installation
• Printed in U.S.A. • ©Honeywell Inc. 1993 • Form Number 69-0504B—2
M3375
!
CAUTION
Disconnect power supply before beginning instal-
lation to prevent electrical shock or equipment
damage.
LOCATION
Locate the thermostat about 5 ft [1.5 m] above the floor
in an area with good air circulation at average temperature.
Do not mount the thermostat where it can be affected by:
— drafts or dead spots behind doors or in corners.
— hot or cold air from ducts.
— radiant heat from the sun, fireplaces, or appliances.
— concealed pipes and chimneys.
— unheated (uncooled) areas such as an outside wall
behind the thermostat.
MOUNTING AND WIRING
Disconnect power supply before beginning installation
to prevent electrical shock or equipment damage.
All wiring must comply with local codes and ordi-
nances.
The T834C can be mounted directly on a wall or
vertical outlet box. Use the 193121A Mounting Plate As-
sembly (order separately) to mount on horizontal outlet box
or cover marks left by old thermostat. If mounting plate
assembly is used, review instructions provided with assem-
bly before wiring and mounting thermostat.
To wire and mount thermostat:
1. In replacement applications, check the existing
thermostat wires for cracked or frayed insulation. Replace
any wires in poor condition. If the wire is plastered into the
wall, make a hole next to the wires and loosen the wires so
they can be pushed back into the wall later.
2. In new installations, run wiring (if necessary) to the
thermostat location.
3. Connect the wires to the terminals on the back of the
thermostat. See Figs. 2-4 for internal schematic and typical
hookup diagrams.
4. Remove thermostat cover by pulling outward on
bottom edge of cover until it snaps free of the thermostat
base. Carefully remove and discard the foam plastic ship-
ping insert. This insert protects the switch and bimetal
assembly during shipping.
5. Set the adjustable heat anticipator indicator to match
the current draw of the primary heating control (see Heat
Anticipator Setting).
6. Push excess wire back through the hole and plug any
opening with insulation to prevent drafts that may affect
thermostat performance.
7. Loosely fasten the thermostat to the wall or outlet
box with a screw through the top mounting hole. Adjust the
thermostat so it is approximately level. Start the second
screw through the bottom mounting hole, but do not tighten.
1 69-0504B—2