Honeywell T822C User Manual

T822C,E

Cooling Thermostats

Application

T822C,E Thermostats provide low voltage control of
cooling systems. Both models have fixed cooling antici­pators and are available with a positive OFF switch and
temperature range stops. The T822E has ON-AUTO fan
switching and OFF-AUTO system switching.

Recycling Notice

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 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 this control, or of an old control containing mercury in
a sealed tube.

If you have questions, call Honeywell at 1-800-468-

1502.

Installation

WHEN INSTALLING THIS PRODUCT...

1. Read these instructions carefully. Failure to fol­low them could damage the product or 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

Disconnect power supply before beginning in­stallation to prevent electrical shock or equip­ment damage.

LOCATION

Locate the thermostat about 5 ft [1.5 m] above the
floor on an inside wall 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 form the sun, fireplaces, or appliances.

—concealed pipes and chimneys.

—unheated (uncooled) areas behind the thermostat

such as an outside wall.

Fig. 1—T822C in typical cooling application
with fan relay.

T822C

TEMP. RISE

R

3

C1

C1
ANTICIPATOR

1

POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.

2

CONNECT FAN TO O FOR CONTINUOUS FAN OPERATION.
CONNECT FAN TO Y FOR FAN OPERATION WITH COOLING
EQUIPMENT CYCLING.

3

POSITIVE OFF SWITCH PROVIDES COMPLETE CONTROL
CIRCUIT SHUTOFF. DOES NOT REPLACE POWER SUPPLY
DISCONNECT SWITCH.

O

2

Y

FAN RELAY

COMPRESSOR
RELAY

L1
(HOT)

L2

1

M1292A

MOUNTING AND WIRING

Disconnect power supply before beginning installa-

tion to prevent electrical shock or equipment damage.

All wiring must comply with local codes and ordi­nances. T822C,E Thermostats are designed to be verti­cally mounted on a wall or an outlet box.

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 that 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. 1, 2, or 3 for internal schemat­ics 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
shipping insert. This insert protects the switch and bi­metal assembly during shipping.

5. Push excess wire back through the hole and plug
any opening with insulation to prevent drafts that may
affect thermostat performance.

6. Loosely fasten the thermostat to the wall or outlet
box with a screw through the top mounting hole. Do not
tighten.

7. Level the thermostat exactly using a spirit level or
plumb line. Tighten the mounting screws.

IMPORTANT: An incorrectly leveled thermostat will

cause the temperature control to deviate from
setpoint.

8. Replace the thermostat cover.

1 69-0548—2J. H. • Rev. 2-93 • • ©Honeywell Inc. 1993 • Form Number 69-0548—2

M3375

Fig. 2—T822C in typical cooling application.

T822C

TEMP. RISE

R

C1

C1
ANTICIPATOR

Y

COMPRESSOR
RELAY

1

POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.

M2305

L1
(HOT)

L2

1

Fig. 3—T822E in typical cooling application.

L1
(HOT)

FAN RELAY

COMPRESSOR
CONTACTOR

L2

T822E

TEMP. RISE

C1

C1
ANTICIPATOR

1

POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.

FAN
SWITCH

ON

AUTO

SYSTEM
SWITCH

AUTO

OFF

R

G

Y

1

M1293

Settings and Adjustment

TEMPERATURE SETTING

Move the temperature setting lever to the desired
control point on the temperature scale. On positive OFF
models, the control circuit is broken when the lever is
moved to the extreme high end of the temperature scale.

T822E FAN AND SYSTEM SWITCHING

The fan switch controls fan operation as follows:

AUTO— fan operates in response to the thermostat

call for cooling.

ON— fan operated continuously.

The system switch controls system operations as
follows:

OFF—cooling control system is disabled.

AUTO—cooling control system operates in response

to the thermostat call for cooling.

RECALIBRATION

These thermostats are calibrated at the factory and
should not need recalibration. If the thermostat seems
out of adjustment, first check for accurate leveling. To
check calibration, proceed as follows:

1. Move the temperature setting lever to the low end

of the temperature scale.

2. Remove the thermostat cover. Move the setting

lever until the switch just makes contact. The mercury in

the switch will drop to the contact end of the tube.

3. Replace cover and wait five minutes for the cover
and the thermostat to lose the heat it has gained from
your hands. If the thermostat pointer and the setting
lever indicator read approximately the same, no
recalibration is needed.

If recalibration appears necessary, proceed as fol-

lows:

1. Place the temperature setting lever at the same
setting as the thermometer. Remove cover.

2. Insert 104994A Calibration Wrench (order sepa­rately) onto the hex nut under the coil. See Fig. 4.
Holding the setting lever so it does not move, turn the
wrench clockwise until the switch just breaks con­tact. Remove wrench and replace cover.

3. Move the setting lever to a low setting. Wait at
least five minutes for temperature to stabilize.

4. Slowly move the setting lever until it reads the
same as the thermometer.

5. Remove cover. Holding the setting lever so it does
not move, reinsert wrench and carefully turn counter­clockwise until the mercury just rolls to the left
end of the tube but no farther.

6. Recheck calibration. Set thermostat system switch
for desired operation and replace cover.

2