Service manual

Page 26 Microcook HD Ovens 32Z3385 Issue 5
TA 1725 and TA 1925 Fan control PCB – part no. 11M0261
This board provides a full temperature-control system for the Turboaire Hot Air Fan, this will need
to be set up in accordance with the following procedure once replaced. It also monitors the Fan
Motor performance, and sends a signal to the logic PCB Assembly to indicate that it is functioning
correctly. The status of the various functions are indicated by the monitor LEDs.
Thermocouple Sensor Input
When power is connected to the oven, the “Sensor Error” LED (D6) should not illuminate. If this
happens, there is a bad connection or a broken wire in the thermocouple sensor. Using a suitably
insulated pair of long nose pliers, short the + & - terminals together (D6) should then go out. If this
does not happen the PCB is faulty and requires replacing.
Thermocouple Operation
Using a multimeter set to read in excess of 1V dc ,connect the black lead to the pin marked
“GND” and the red lead to the pin marked “T+”. A reading in millivolts of ten times the nozzle
temperature should be obtained:
If the nozzle is at 22.0 C, then the reading should be 220mV
If the nozzle is at 19.2 C, then the reading should be 192mV