User Guide

CHECKOUT

After installing a thermostat, make an initial check of the switching action. Verify the switch

action by listening to and watching the switch contacts, using a voltmeter between the proper

sides of the switch, or by observing the controlled device.

1. Run the setpoint dial to a temperature above ambient. This should cause the thermostat

to switch, calling for heat.

2. Turn the setpoint dial setting down gradually. The switch should break contact.

CALIBRATION

All thermostats are calibrated at the factory and normally will not require any such attention.

However, if recalibration is necessary for any reason, proceed as follows:

1. Disconnect power to thermostat.

2. Set the adjusting dial to correspond to actual room temperature.

3. Remove thermostat cover, remove screw that secures right-hand side of insulator, fold

back insulator, and remove contact cover. (See Figure-3.)

C A U T I O N

Do not breathe on the thermostat or handle excessively as this will affect the accuracy of the

final calibration.

4. If contact blade is made to the left (R) contact, use a 3/16" open end wrench (TOOL-11)

to turn calibration screw counterclockwise (looking at head of screw) until blade just

breaks contact. Thermostat is now properly calibrated.

N O T E

Each complete revolution of screw changes calibration approximately 8°F.

5. If contact is not made to the left, turn the calibration screw slowly clockwise until ele-

ment makes to the R contact. Thermostat is now properly calibrated.

6. Replace contact cover insulator and thermostat cover.

7. Restore power to thermostat.

8. Recheck calibration about 30 minutes later to be sure heat from handling did not result

in erroneous setting.

Contact Cover

Contact Blade

Adjusting Dial

Optional

Night Depression

Resistor

Insulator

Detent

Magnet

“R” Contact

Calibration Screw

Bimetal Element

Figure-3 Part Identification.