AccuTemp XLR81B-00 Series Install, Service And Parts page 15

2.2 TROUBLESHOOT GUIDE
A
Incorrect voltage supplied
B
Error code
C
Unit not calling for heat.
Unit not achieving set
D
temp
MP5032-2104
The unit is designed to work with 120V. Check that the original OEM plug is
still being used and there is no damage to the cord. Verify correct voltage at
receptacle.
If the display is showing Err, that is a sign the control board does not detect
a temperature sensor connection. Access the control board and inspect
the three RTD connections at J3, J4 & J5. If connections look good, test
resistance across the black and white wires for each RTD. Compare to the
table on page **
Check which preset has been selected on the digital control. There are three
LED lights on the control panel. Each corresponds to the call for heat to one
of three elements in the platen. When the unit is calling for heat, the lights
will flash. If the lights are steady, the control believes it has reached set point
and has stopped the call for heat.
If the lights are flashing, but the unit temp is not increasing:
1. Remove controller cover.
2. Disconnect the harness with a white and black wire that is attached to
the fuse.
3. Disconnect the black harness from terminal J2-2 and the white with
orange wire harness from terminal J7-1.
4. Ohm across the two white wires removed. If open then a lead wire
to the bimetal thermostats or a bimetal thermostat is opened. Let the
heaters cool then retest.
5. If still open, disassemble the heater box and test for the open bimetal
thermostat.
6. If closed then look for a broken connection or burnt wire in the red
harness. If the red harness and connections are good then replace the
controller.
If the lights are not flashing and unit temp does not increase:
1. Replace the controller. To have all three not flashing on warm up is not
a likely event. All three RTDs would have to be damaged to the set point
value which is highly unlikely.
If the unit is heating but cycling at a lower/higher temp than set point:
1. Check unit presets are correct (see programming instructions on page 8).
2. When unit has reached cycle point, temp all three platen zones using a
direct contact thermometer with a small amount of cooking oil applied.
Verify if unit is reaching set temp within 10°F±.
3. If temp is not matching set point. Access unit control.
4. Remove white and black wires leading to one of three RTDs and take a
resistance reading across them. Compare to the table on page **.
5. If RTD reading matches current platen temp, replace control board.
6. If RTD reading is o of current platen temp, replace RTD. Continue to test
each RTD in turn.
XLR8 HEATED PLATEN
14