Settings and adjustments, Calibration, New applications – Honeywell HEAT THERMOSTATS T4398A User Manual

Page 4: Check calibration

Advertising
background image

T4398A,B HIGH PERFORMANCE ELECTRIC HEAT THERMOSTATS

68-0147—2

4

WALL

MOUNTING
SCREWS (2)

M5797

OUTLET
BOX

THERMOSTAT
BASE

8

0

7

5

7

0

65

60

55

50

SETTING DIAL
INDICATOR

M5791B

L1
(HOT)

L2

L1

T1

1

2

4

3

SOLDERLESS
CONNECTORS

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

USE SPECIAL SERVICE CO/ALR SOLDERLESS CONNECTORS
WHEN CONNECTING ALUMINUM CONDUCTORS OR A FIRE
HAZARD MAY RESULT.

USE A SEPARATE LIMIT CONTROL IN THE HEATING APPLIANCE.

BREAKS AND REMAKES BELOW -31°F (-35°C); NORMALLY
THERMAL ACTIVATED. BREAKS ON TEMPERATURE RISE;
MAKES ON TEMPERATURE FALL.

1

2

3

4

T4398A

ELECTRIC
HEATER

Fig. 2. Typical wiring connections for T4398A.

Fig. 3. Typical wiring connections for T4398B.

M5792B

L1
(HOT)

L2

L1

T1

1

2

4

SOLDERLESS
CONNECTORS

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

USE SPECIAL SERVICE CO/ALR SOLDERLESS CONNECTORS
WHEN CONNECTING ALUMINUM CONDUCTORS OR A FIRE
HAZARD MAY RESULT.

BREAKS AT POSITIVE OFF AND REMAKES UNDER –31°F (–35°C);
NORMALLY THERMALLY ACTIVATED. BREAKS ON TEMPERATURE
RISE; MAKES ON TEMPERATURE FALL.

USE A SEPARATE LIMIT CONTROL IN THE HEATING APPLIANCE.

BREAKS AT POSITIVE OFF ONLY; NOT THERMALLY ACTIVATED.

DO NOT CONNECT GROUNDED CONDUCTOR (NEUTRAL) ON
120 OR 227V CIRCUITS. INSULATE AND TAPE OR CUT OFF
RED WIRES IF UNUSED.

1

2

3

4

5

6

5

L2

T2

3

ELECTRIC
HEATER

RED
WIRE

6

T4398B

Fig. 4. Mounting thermostat to outlet box.

New Applications

Disconnect power supply to prevent electrical shock or
equipment damage. All wiring must comply with local
electrical codes and ordinances.

Run line voltage wiring to the thermostat location.

Do not remove T4398 Thermostat Cover. Using wire
connectors approved for No. 12 wires, make line
voltage connections directly to leadwires on thermostat.
See Figs. 2 and 3 for typical wiring connections.

Prebend and push solid wires into the outlet box.

Remove the thermostat cover by grasping the top and
bottom edges and pulling outward away from the base.

Turn the setting dial so indicator is at the 12 o’clock
position to prevent damaging the sensing element when
mounting the thermostat.

Mount the thermostat on the outlet box as shown in
Fig. 4. Secure the thermostat by tightening the two
mounting screws.

SETTINGS AND ADJUSTMENTS

Calibration

The T4398 Thermostats are calibrated at the factory using
precise instruments under closely controlled conditions.
Recalibration should not be necessary. Allow the thermostat
to operate for several hours before checking calibration. The
T4398 Thermostat vapor-filled dual diaphragm sensing
element is affected by barometric pressure and altitude.
Temperature deviations of 1

°

F (0.5

°

C) are normal. If the

thermostat is mounted in a suitable location (as instructed in
the Location section) and still appears out of calibration,
check calibration as follows.

Check Calibration

Remove the thermostat cover and set it aside for
several minutes because radiant heat from your hands
will affect the thermometer reading.

Turn the setting dial clockwise until the switch makes
(click sound). The heating equipment and fan start.

No recalibration is necessary if the thermostat switch
makes with the thermostat setting at the same
temperature as indicated on the thermostat cover
thermometer.

Advertising
This manual is related to the following products: