T
ROUBLESHOOTING
Heated Shelf Merchandiser
?
Service Manual
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MN-39054
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Rev 1
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4/17
38
One Shelf Not Heating
Turn the temperature
control for the shelf that is
not heating to the highest
number.
Yes
Measure the voltage at
the L1 and L2/N terminals
of the temperature
controller.
No
Is the green indicator
light illuminated for the
shelf that is not heating?
Does the measured
voltage correspond to the
voltage printed on the
serial number tag?
Yes
Remove electrical power
from the unit. Measure
the resistance value of the
heating pad.
Does the heating pad
have the correct
resistance value?
No
Replace the heating pad.
Yes
Repair the wire
connections at the
terminal block.
Yes
Measure the resistance
value of the RTD
temperature sensor for
the shelf that is not
heating.
No
Measure the voltage at
terminal blocks
L1 to L2/N.
Does the temperature
sensor have the correct
resistance value?
No
Replace the RTD
temperature sensor.
Repair or replace the
wiring to terminal blocks
L1 to L2/N.
No
Does the voltage
correspond to the voltage
printed on the serial
number tag?
Yes
The temperature
controller has failed.
Replace the temperature
controller.