Impinger I -–1000 Series Service Manual - Domestic 51
TEMPERATURE GAUGE - REPLACEMENT
1. Shut off power at main bre aker.
2. Remove control panel to p.
3. Disconnect thermoc ouple from temperature gauge.
4. Remove two (2) mounti ng bolts and remove temperature gauge.
5. Reassemble in revers e order.
THERMISTOR - REPLACEMENT
1. Shut off power at main bre aker.
2. Remove control panel to p.
3. Slide thermistor probe out of oven chamber.
NOTE: Remove conveyor and bottom fingers to aid in removal and instaliat icn of thermistor probe.
4. Disconnect wires from back of digital display at terminal strip (location #9-10).
5. Reassemble in revers e order making sure the probe is placed securely in the wire form in the oven
chamber.
6. Reconnect to digital disp lay and calibrate. (See Time/Temperature Display - Replacement and
Calibration)
To test the thermistor probe, refer to the following chart and instructions
OVEN TEMPERATURE
300º F 325º F 350º F 400º F 425º F 450º F 500º F 550º F
OHMS 182 138 102 62 48 38 24 16
Place test pyrometer thermocouple and preheat oven as specified under tem perature calibration.
Disconnect the thermistor probe from terminals 9 and 10 and measure the res istance across the 2 yellow
leads. Refer to the above chart to determine if probe is producing the proper res istance.
EXAMPLE: The probe resistance at 500°F(260°'C) should be 24 ohms.
TRANSFORMER, TIME/TEMP. DISPLAY
1. Shut off power at main bre aker.
2. Remove control panel to p.
3. Remove relay box cover .
4. Disconnect two (2) wires at base of transformer and three (3) wires at terminals 1,2, and 3 on Time/Temp
Display.
5. Remove two (2) mounti ng screws.
6. Reassemble in revers e order.
TIME/TEMPERATURE DISPLAY - REPLACEMENT & CALIBRATION
1. Shut off power at main bre aker.
2. Remove control panel to p.
3. Disconnect wires from rear of display. Make note of wire numbers and location for reinstallation.
4. Remove four (4) scr ews from display bezel (2 top/2 bottom) and remove display.
5. Install new display in rev erse order. Note dip switch position and calibrate display as follows:
a) Check all wire connections to insure proper ti ghtness.
b) Check dip switch setting to insure proper pos itions for the model of oven: