Environmental Technologies Air Terminal Unit SDR-WC-10

Disconnect actuator from the controller.

Apply 24 VAC to the COM and CW terminals on the actuator.

Did the actuator rotate in a clockwise direction?

Apply 24 VAC to the COM and CCW terminals on the actuator.

Did the actuator rotate in a counter clockwise direction?

Did the actuator move in both directions?

Is the actuator at an end stop or is there a problem with the damper?

Loosen the set screw to free the actuator from the damper shaft.

Refer to the 'Electric Heat, All Products' IOM for complete electric heater installation, operation and maintenance information.

Check if the primary auto-reset limit switch is functioning properly.

Did the secondary one-time trip limit switch trip?

Replace the secondary limit switch with one that has the same trip temperature if it has tripped.

Is there an optional manual reset secondary limit switch installed?

Reset the manual reset secondary limit switch by depressing the reset switch, if applicable.

Verify airflow is at least 70 CFM per kW.

Mechanical Angle of Rotation Stops

Loosen the two end stop screws using a No. 2 Phillips head screwdriver

Ensure not to unscrew the captive nut under the slot

Move the stops to the desired position (in 2.5° steps)

Electric Heater Rack Replacement

Turn off power supply before servicing

Locate T-Plate inside on heater control enclosure

Mark where the wires are connected on the T-Plate before removal

Remove the wires and screws holding the heater T-plate in the control enclosure and remove element rack

Insert new element rack into control enclosure and replace screws to secure the element rack to control enclosure

Close control enclosure cover before turning on the power

Disconnect all electrical power to the equipment, tag and lock out power source.

Gain access to coil either through ductwork or optional coil access panel.

Use soft brush and vacuum to remove loose debris from sides of coil.

Straighten any coil fins that may have been damaged during cleaning process with fin comb.

Replace ductwork or access panel and restore electrical power to equipment.