Forma Scientific 3158 - Component Replacement; Replacing the CO2 Sensor and Triac

Forma Scientific, Inc.
7-10
Extend the control panel out only far enough to access the
circuit board and limit activity to the board.
3. Locate the variable resistor identified as “zero” among the circuit board
components. The resistor is a long, narrow device with a slotted, brass screw on
the top.
4. Match the display with the thermometer reading by rotating the screw
counterclockwise to raise the the temperature, clockwise to lower it.
7.5 REPLACING THE CO
2
SENSOR
1. Remove shelves, duct sheets, and blower channel from the chamber.
2. Locate CO
2
sensor, and remove wing nuts. The sensor will drop down.
3. There is a clip that connects sensor wiring to incubator wiring. To open the
clip, pull out slightly on the clip tab to release the sensor.
4. Remove the O-ring, and place it on the new sensor.
5. Clip the new CO
2
sensor onto the incubator wiring and return the sensor to
its original opening. Tighten the wing nuts securely to properly seal the
O-ring.
6. After the sensor has been replaced, calibrate the CO
2
controller according
to the instructions in Section 7.2.
7.6 REPLACING THE TRIAC (REFER TO WIRING DIAGRAM 140181-71-0-D)
1. Turn the incubator off and disconnect it from the power source.
2. Loosen the two 1/4-turn fasteners on the front of the control panel and pull
the panel out.
3. Open the incubator outer door to gain access to the triac mounting screws
from underneath the control panel.