Wolf WWD30 User manual

5-2
Troubleshooting Guide WARMING DRAWER WWD30
TROUBLESHOOTING GUIDES
This section of the manual contains the General Troubleshooting Guide which will help the Service Technician trou-
bleshoot a Wolf WWD30 unit. Following the General Troubleshooting Guide is the Electronic Control System Test
Procedures to be performed after going through the General Troubleshooting Guide and determining that the elec-
tronic control system is suspect.
How to Use the General Troubleshooting Guide
The Table of Contents below indicate how the General Trouble Shooting Guide on the following pages is arranged.
Locate the description of the problem that the unit is experiencing from the Table of Contents, below. To the left of
the problem description in the Table of Contents is a letter. On the page indicated, locate that letter in the left col-
umn of the General Troubleshooting Guide. The center column of the General Troubleshooting Guide will identify
the possible causes for the problem. The information in the right column of the General Troubleshooting Guide will
explain what tests to perform and/or what action to take to correct the problem.
Before continuing, take note of the WARNINGS and CAUTIONS at the bottom of this page.
General Troubleshooting Guide Table of Contents
Page #
Error Codes Troubleshooting Guide .............................................................................................................................................. 5-3
A. Unit does not function at all ................................................................................................................................................... 5-4
B. No Heat at Any or All Settings ............................................................................................................................................... 5-4
C. No Heat at PROOF Setting only ........................................................................................................................................... 5-4
D. Excessive Heat at Any or All Settings .................................................................................................................................... 5-4
E. Excessive Condensation in Drawer ....................................................................................................................................... 5-4
F. Food Dries Out ...................................................................................................................................................................... 5-5
G. One or more LCD (ON/OFF indicator, Temp. Range Indicator or segment(s) of Temp. Readout) does not illuminate ....... 5-5
H. LCD is black ........................................................................................................................................................................... 5-5
I. One or more LCD (ON/OFF indicator, Temp. Range Indicator or segment(s) of Temp. Readout) illuminated Constantly .. 5-5
J. Drawer Does Not Slide Smoothly .......................................................................................................................................... 5-5
K. Drawer Does Not “Pull In”........................................................................................................................................................ 5-5
- IF REMOVING A WARMING DRAWER FROM ITS INSTALLATION FOR TROUBLESHOOTING PURPOSES, REMEMBER
THAT THE UNIT IS HEAVY AND COULD TIP AND/OR FALL WHEN PULLED FORWARD BEYOND THE ANTI-TIP COM-
PONENTS, RESULTING IN SERIOUS INJURY OR DEATH.
- TO AVOID ELECTRIC SHOCK, POWER TO THE UNIT MUST BE DISCONNECTED WHENEVER ACCESSING AND/OR
REMOVING COMPONENTS POWERED BY ELECTRICITY OR COMPONENTS NEAR OTHER ELECTRICAL COMPO-
NENTS. IF THE UNIT IS PLUGGED IN, BUT HAS NOT BEEN SWITCHED ON BY PRESSING THE UNIT ON/OFF KEY,
115 VOLTS AC IS STILL PRESENT AT THE POWER BOARD.
- Metal edges may be sharp. Use caution when servicing unit to avoid personal injury.
- The heating element can get very hot. To avoid personal injury use caution when servicing the unit,
making sure the heater has cooled before working on or around it.
- If accessing components under the shell, the insulation must be properly reinstalled and positioned.
Failure to do so may lead to damage to the surrounding cabinetry.
- Low voltage is used for most electronic control components. To avoid damaging the appliance, do NOT
apply 115V AC to electronic control components.
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Troubleshooting Guide
WARMING DRAWER WWD30
5-3
ERROR CODE TROUBLESHOOTING GUIDE:
ERROR CODE CAUSE TEST / ACTION
10
(Invalid Checksum Error)
20
(Thermistor Open)
30
(Thermistor Short)
40
(Element Sensing)
50
(Door Switch)
60
(Stuck Relay)
70
(Cable Open)
Incorrect checksum
Temperature >300ºF
Temperature <-30ºF
<5º change in temperature over 10
minutes of continuous call for heat.
Occurs only during preheat mode and
the door is closed.
Door switch closed when the keypad is
being operated or unit turned on.
Drawer temperature rises to 250ºF in
any mode/state.
Cable wires that activate element or
fan relays on power board are not
making connection.
Replace Control Board
In FSM (Field Service Mode), view temper-
ature as view by thermistor. Verify wiring
ok to element. Replace Thermistor if ok.
In FSM (Field Service Mode), view temper-
ature as viewed by thermistor. Verify wiring
ok to element. Replace Thermistor if ok.
If unit outdoors and temperature below
freezing point, instruct on unit limitations.
Verify Thermal Cutout is not open.
Verify Element is not open.
Replace TCO or Element if open.
Check operation of Door Switch with Ohm
meter. Replace if defective.
Check ambient Temp and installation.
Check TCO. Replace if opened.
Replace Relay Board.
Check connection of comm cable. Use
Figure 5-1 to check voltage and/or ohm
reading of cable. If open, replace.
P1 - Blue / 17VAC
P2 - Orange / 17VAC
P3 - White / Cable Gnd
P4 - Green / Relay Supply Voltage
P5 - Red / Fan Relay Actuation
P6 - Black / Heater Relay Actuation
Figure 5-1 Communication Cable Pin Configuration
NOTE: After correcting problem, errors must first be cleared in Field Service Mode before controls will refresh error
display. To clear error codes logged, press and hold “TIMER” up and down arrow keys for 5 seconds, while in Field
Service Mode.
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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
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Troubleshooting Guide
WARMING DRAWER WWD30
5-5
PROBLEM POSSIBLE CAUSE TEST / ACTION
F. Food Dries Out
G. One or More LCD does not
Illuminate
H. LCD display is black
I. One or More LCD Illuminated
Constantly
J. Drawer Does Not Slide
Smoothly
K. Drawer Does Not “Pull In”
Temperature Setting too High
Food Uncovered
Food in Drawer too Long
No Power to Unit
Unit Switched OFF
(NOTE: See Automatic Shut-off
Information in Section 3.)
Door Switch Faulty
Electronic Control System Fault
Disconnected or Broken Wiring
Contrast set to low
Contrast is set to high
LCD exposed to direct sunlight
Electronic Control System Fault
Drawer Overloaded (Exceeding 80 lbs.
limit) or Unbalanced Load
Drawer Glides Misaligned
Drawer Frame Skewed
Drawer Glides Defective
Self-Close Feature Broken
Slide Mounting Screw is Loose
Something Fell Behind Drawer
Reduce temperature setting.
Cover food with lid or aluminum foil.
Food in drawer longer then 4 hrs. will tend to dry
out. Instruct Customer. (Timer default is 4 hrs.)
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.
Use ohm meter to verify switch operation.
Replace switch if faulty.
See Electronic Control System Test Procedures
following General Troubleshooting Guide.
Check all electrical connections and wires.
Reconnect or repair wiring.
Adjust contrast level
Adjust contrast Level
Allow to cool. Block from direct sunlight.
Instruct Customer.
See Electronic Control System Test Procedures
following General Troubleshooting Guide.
Reduce and/or redistribute drawer contents.
Open drawer fully and close, then reopen and
check operation. If problem persists, see Drawer
Frame Skewed and Drawer Glides Defective,
below.
Remove drawer tub and inspect frame. If
skewed, straighten.
Remove drawer tub and inspect glide operation.
Replace if defective.
Replace Slide. (Wolf Recommends to replace
ALL slides at same time)
Tighten or Replace Screw
Remove Obstruction
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