Viking DCH3042 User manual

Service
Manual
Chimney / Wall
Ventilation
Hoods
Preferred Service
Models
DCH3042
DCH3642
DWH3006
DWH3606
RDWHC3042
RDWHC3644
SMV-0001A
April 2012
®
This manual is to be used by qualied appliance technicians only. Viking
does not assume any responsibility for property damage or personal
injury for improper service procedures done by an unqualied person.
This Base Manual covers general and
specic information including, but not
limited to the following models:

Table of Contents
B ©2012 Viking Preferred Service
Safety Information .......................................................... 3
Save These Instructions........................................... 3
General Information........................................................ 4
Performance Chart – DWH30SS – DWH36SS........ 4
Performance Chart – DCH/ RDWHC 30SS – DCH/
RDWHC 36SS ......................................................... 4
DWH30 (30") – DWH36 (36") Designer wall hoods . 5
Filters .................................................................... 6
Motors................................................................... 6
Ait ow .................................................................. 7
Airow routing ....................................................... 8
Electrical connections ........................................... 8
Disassembly ................................................................... 9
LIGHT OPERATION................................................11
Troubleshooting.............................................................11
FAN OPERATION (Low Speed)............................ 12
FAN OPERATION (High Speed)........................... 13
FAN OPERATION (High Speed Thermostat)......... 14
FAN OPERATION (High Temperature Thermostat)15
Wiring Diagrams........................................................... 16
DWH30/36SS Diagram .......................................... 16
DCH/RDWHC 30SS (30") – DCH/RDWHC 36SS (36")
Professional wall hood ........................................... 17
General Information...................................................... 17
Disassembly ................................................................. 18
Electrical Connections, Input .............................. 19
Thermostat and Switch access........................... 20
Dimmer and Motor Speed Controls .................... 21
Troubleshooting............................................................ 22
LIGHT OPERATION (Low)..................................... 22
LIGHT OPERATION (High).................................... 23
MOTOR OPERATION (Low).................................. 24
MOTOR OPERATION (High) ................................. 25
FAN OPERATION (High Temperature Thermostat)26
Wiring Diagrams........................................................... 27
DCH/RDWHC 30/36SS Wiring Diagram................ 27

!
DANGER!
CAUTION!
WARNING!
WARNING!
CAUTION!
Safety Information
©2012 Viking Preferred Service C
SAVE THESE INSTRUCTIONS
REVIEW ALL SERVICE INFORMATION IN THE APPROPRIATE SERVICE MANUAL AND
TECHNICAL SHEETS BEFORE BEGINNING REPAIRS.
Pride and workmanship go into every product to provide our customers with quality appliances. It
is possible, however, that during the lifetime of a product service maybe require. Products should
be serviced only by a qualied authorized service technician who is familiar with the safety
procedures required to perform the repair and is equipped with the proper tools, parts, testing
instruments, and the appropriate service manual.
Safety Information
We have provided many important safety
messages throughout this manual and on
the product. Always read and obey all safety
statements. To properly identify a safety
statements look for the following safety alert
symbol.
This symbol alerts personnel to hazards
that can many different types of altering
messages. All safety messages will be
preceded by a safety alert symbol and the
word “DANGER”, “WARNING” or “CAUTION”.
All safety messages will identify the hazard,
tell you how to reduce the chance of injury,
and inform you what can happen if the
instructions are not followed.
Immediate hazards which WILL result in severe
personal injury or death.
Hazards or unsafe practices which COULD
result in severe personal injury or death.
Hazards or unsafe practices which COULD
result in minor personal injury, product or
property damage.
To avoid risk of serious injury or death, repairs
should not be attempted by unauthorized
personnel.
VIKING will not be responsible for any injury
or property damage from improper service
procedures. If performing service on your own
product, you must assume responsibility for any
personal injury or property damage which may
result.
To locate an authorized service agent, call:
Viking Customer Service
Phone No. 1-888-845-4641
Address your written correspondence to:
Viking Preferred Service
1803 HWY 82 West
Greenwood, MS 38930

General Information
4©2012 Viking Preferred Service
Performance Chart – DWH30SS – DWH36SS
Performance Chart – DCH/ RDWHC 30SS – DCH/ RDWHC 36SS

General Information
©2012 Viking Preferred Service 5
DWH30 (30") – DWH36 (36") Designer wall hoods
The 30 and 36 inch designer wall hoods are designed to operate both in a recirculation
mode as well as exterior discharge mode. FIG 1 and 2 below shows the underside of the
30" wall hood
FIG. 1 FIG. 2
The unit comes with a two-speed dual blower motor and a two level light selection,
both controlled by two center mounted rocker sw itches. Each switch has a center OFF
position. FIG 3 shows a close-up of the switches.
FIG. 3

General Information
6©2012 Viking Preferred Service
When the hood is installed to operate in recirculation mode, the addition of charcoal lters
(supplied in kit) is required. FIG 4 shows the standard lter used when the hood is installed
for exterior discharge.
FIG. 5FIG. 4
Standard Filter – Exterior Discharge Recirculation – Charcoal Filter Added
The charcoal lter is held in place with four securing clips (Included with charcoal lter) as
shown in FIG 5 above.
Remove lters to access the internal blower motors. FIG 6 shows that the motor assembly
consists of two motors, one which rotates in a Cloc kwise rotation (Below right) and the other
in a counter-clockwise rotation (Below left). Each motor is connected separately to the control
housing by the use of a 4-wire Molex disconnect plug (Inset).
FIG. 6
Recirculation installation shown

General Information
©2012 Viking Preferred Service 7
The air drawn in through the lters is regulated back into the kitchen through a top vent that
runs the length of the hood as shown in FIG 7.
FIG. 7
In FIG 8, the blower motor assembly has been rotated 180° for rear and top external
discharge. There are (2) 5/16th nuts that secure the blower assembly to the hood housing.
The insets below show each side where the nut is located (circled in red). The right one is
just above the main power connection
FIG. 8

FIG. 13
General Information
8©2012 Viking Preferred Service
When the unit is installed for exterior venting, a duct connection collar is attached to the
hood and allows connection to external ducting. FIG 9 shows the hood with the vent collar
attached for rear discharge. Notice a back draft damper is built into the collar. FIG 9 also
shows the top access cover is in place
FIG. 10FIG. 9
FIG 10 shows the rear of the hood with the damper removed. Notice the two squirrel wheels
in place for rear discharge
Junction box (for incoming power supply) is located in upper right rear of hood.. Inside the
hood a three wire power cable exits the junction box (Fig 11) and connects to a xed (male)
three prong plug (FIG 12) in the component compartment of the hood. If the lights and
fan are not working, unplug the internal power plug and check for 120 volts at the female
connection shown in Fig 13.
FIG. 12FIG. 11
Fixed three prong connection

To avoid risk of electrical shock, personal injury, or death, disconnect electrical power source to unit, unless test
procedures require power to be connected. Discharge capacitor through a resistor before attempting to service.
Ensure all ground wires are connected before certifying unit as repaired and/or operational.
WARNING!
Disassembly
©2012 Viking Preferred Service 9
To access internal controls, remove left and right side trim held in place with (2) Phillips head
screws shown in FIG 14 and Fig 15.
FIG. 14 FIG. 15
There are ve Phillips head screws that hold the control panel in place. One on each
side, one in the center and two that hold the lter supports in place, FIG 16 shows one of
the side screws and lter support screw. The screw circled in red holds the component
compartment to the main frame and must be removed to access the switches and
thermostats.
FIG. 16
FIG. 17
With the screws removed, remove the power and motor connection mounting plate from the
hood. Internal wiring of the power connections is now accessible as shown in FIG 17.

To avoid risk of electrical shock, personal injury, or death, disconnect electrical power source to unit, unless test
procedures require power to be connected. Discharge capacitor through a resistor before attempting to service.
Ensure all ground wires are connected before certifying unit as repaired and/or operational.
WARNING!
Disassembly
10 ©2012 Viking Preferred Service
Remove the light and switch compartment. Remove screws securing the panel to the
frame of the hood. One in the center and one next to each canopy light. FIG 18 shows the
location of the right side screw that secures the panel housing. (Removed in photo).
FIG. 18
Lift the control panel from the frame to expose the internal operational components. FIG
19 shows the Fan Switch, Light Switch, Hi-Temp Thermostat, High Speed Thermostat and
halogen light socket.
FIG. 19

Troubleshooting
©2012 Viking Preferred Service 11
LIGHT OPERATION
When the lights are switched to position I (Low), the current runs through the light switch,
through the diode which reduces the voltage to the lights. The lights will operate in a low-light
condition.
When the lights are switched to position II (High), the current runs through the light switch
and directly to the lights. The lights will operate at full power.

Troubleshooting
12 ©2012 Viking Preferred Service
FAN OPERATION (Low Speed)
When the fans are switched to position I (Low), the current runs through the fan switch,
through the Common and Normally closed (N.C.) contact in the High speed thermostat. From
there the current is sent to both low speed windings in the motors. The fans will operate in a
low speed condition.

Troubleshooting
©2012 Viking Preferred Service 13
FAN OPERATION (High Speed)
When the fans are switched to position II (High), the current runs through the fan switch
directly to both high speed windings in the motors. The fans will operate in a high speed
condition.

Troubleshooting
14 ©2012 Viking Preferred Service
FAN OPERATION (High Speed Thermostat)
If the fans are set to run at low speed and the temperature in the hood exceeds 160°
Fahrenheit, the Fan speed thermostat will switch to the Normally Open Contact and switch
power from the low speed windings to the high speed windings. When the temperature
drops below 160°, the thermostat will switch back to the Normally Closed contact and the
fan speed will revert to low operation.

Troubleshooting
©2012 Viking Preferred Service 15
FAN OPERATION (High Temperature Thermostat)
If at any time the interior of the hood exceeds 160° F, the High Temp thermostat will close and
operate the fans at HIGH speed. When the temperature drops below 145°, the High Temp
Thermostat will open fans will shut off or revert back to previous condition.

Wiring Diagrams
16 ©2012 Viking Preferred Service
Wiring Diagram
DWH30SS
DWH36SS

General Information
©2012 Viking Preferred Service 17
DCH/RDWHC 30SS (30") – DCH/RDWHC 36SS (36") Professional wall hood
The 30 and 36 inch Professional wall hoods are designed to operate as exterior
discharge mode only. FIG 1 below shows the underside of the 30" wall hood.
FIG. 1
The unit comes with a variable speed blower motor and a variable level light selection,
both controlled by two center mounted On-Off push button switches.
FIG 2 shows a close-up of the light controls and FIG 3 shows the fan controls.
FIG. 2 FIG. 3

To avoid risk of electrical shock, personal injury, or death, disconnect electrical power source to unit, unless test
procedures require power to be connected. Discharge capacitor through a resistor before attempting to service.
Ensure all ground wires are connected before certifying unit as repaired and/or operational.
WARNING!
Disassembly
18 ©2012 Viking Preferred Service
To access to the blower motor and internal switches, remove the lters. FIG 4 shows two
trims that run the length of the hood, both front and rear, as well as the center support and
are held in place with six Phillips head screws. Remove all three supports.
FIG. 4
The blower assembly consists of the motor and two squirrel cage blower wheels, one at
each end of the motor. The left side wheel is shown in FIG 5. FIG 6 shows the right side
blower wheel, along with the internal power and motor connections.
FIG. 5 FIG. 6

To avoid risk of electrical shock, personal injury, or death, disconnect electrical power source to unit, unless test
procedures require power to be connected. Discharge capacitor through a resistor before attempting to service.
Ensure all ground wires are connected before certifying unit as repaired and/or operational.
WARNING!
Disassembly
©2012 Viking Preferred Service 19
In the top rear center of the hood is where the main wire connections are made by the
electrician. Inside the hood a three wire power cable exits the junction box and connects to a
xed (male) three prong plug (shown unplugged in FIG 7 in the component compartment of
the hood. If now power is coming out of the J-Box, a three wire grounded extension cord can
be used to test the operation of the hood.
FIG. 7
FIG. 8
Fig 8 shows the motor and power
connection both connected.
To access the internal switches and connections, there are 4 Phillips head screws that must
be removed. FIG 9 shows the right front corner of the hood looking towards the front. With
the light bulbs removed, remove both securing screws on each side of the hood. A 6" long
Phillips head screwdriver (7-10" long) will be required to reach the screws. Two screws (one
on each side come forward into the front frame).
FIG. 9 FIG. 10
FIG 10 shows the side screws
location accessed through
the rear slotted opening in the
panel.

To avoid risk of electrical shock, personal injury, or death, disconnect electrical power source to unit, unless test
procedures require power to be connected. Discharge capacitor through a resistor before attempting to service.
Ensure all ground wires are connected before certifying unit as repaired and/or operational.
WARNING!
Disassembly
20 ©2012 Viking Preferred Service
FIG 11 and FIG 12 show the left front screw location accessed through the light bulb
openings. This view is looking forward from inside the hood. Suggest using a handheld
mirror to locate screws while disassembling and reassembling.
FIG. 11 FIG. 12
Lift the control panel compartment from inside the hood to access the Light sockets,
control switches, High Temp Thermostat, Speed Control and light dimmer. FIG 13 shows
the internal compartment, which houses the incoming power, Dimmer control, Speed
Control, On / Off switches and High Temperature thermostat.
FIG. 13