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5-4
Troubleshooting Guide
WARMING DRAWER WWD30
PROBLEM
POSSIBLE CAUSE
TEST / ACTION
A. Unit Does Not Function at All
B. No Heat at Any or All
Settings
C. No Heat at PROOF Setting
Only
D. Excessive Heat at Any or All
Settings
E. Excessive Condensation in
Drawer
No Power to Unit
No power from power board
Disconnected Cable or Broken Wiring
No Power to Unit
Unit Switched OFF or no keypress made
within 20 seconds after turning on.
Electronic Control System Fault
Disconnected or Broken Wiring
Defective Heating Element
Defective Thermal Cutout (TCO)
High Room Ambient
Electronic Control System Fault
Defective Heating Element
Defective Thermal Cut-Out
Defective Thermistor
Check Offset in FSM (Default is “0”)
Temperature Setting too High
Uncovered Food in Drawer
Liquid in Drawer
Check power to unit. Plug unit in, switch supply
circuit breaker to ON position or replace fuse if
defective.
Check for power from power board. Replace if
no voltage present.
Check for power from power board. Replace if
no voltage present.
Check power to unit. Plug unit in, switch supply
circuit breaker to ON position or replace fuse if
defective.
Switch unit ON and set to desired temperature.
See Electronic Control Section for operational
information. After turning unit on selection must
be made within 20 seconds or unit turns off.
Check all electrical connections and wires.
Reconnect or repair wiring.
Check heater for 16.9 Ohms (±10%) or open.
Replace if outside range or open.
Check resistance of thermal cutout.
Replace if open.
If room ambient exceeds temperature setting of
warming drawer, it will not work. Instruct
Customer.
See Electronic Control System Test Procedures
following General Troubleshooting Guide.
Check heater for 16.9 Ohms (±10%). Replace
if outside range or open.
Check resistance of thermal switch when hot
(heat with lighter). Replace if it remains closed.
Check resistance at room temperature (70°F /
21°C). Resistance should be 12.9K Ohms
±10%. Replace if out of range or open.
NOTE:
See Section 6 for further Thermistor
Testing Information.
Adjust offset ±30 in FSM.
Reduce temperature setting.
Cover food with lid or aluminum foil.
Remove liquid. If outdoors, verify door shuts.
General Troubleshooting Guide
