Merco Hot Dog Grill SG-22 Quick start guide

PARTS & SERVICE MANUAL for SG Series Hot Dog Grills
Model SG-22 Hot Dog Grill
(Shown with SW-22 Food Warmer)
1200-JDM 07087
THIS MANUAL SHOULD BE RETAINED FOR FUTURE USE

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WARNING: DISCONNECT UNIT FROM POWER SOURCE BEFORE ATTEMPTING ANY SERVICE PROCEDURE
General Information: The units covered in this Parts
and Service Manual, SG-18, SG-22 and SG-34, are
engineered for efficient, dependable service throughout
the years. Like any piece of fine equipment with moving
parts and broad temperature ranges, physical ware
takes its toll. When this happens, the information found
in this manual will prove most helpful. Although the
instructions are easy to follow, the work should be
carried out by a qualified Service Technician.
General Instructions: The following instructions refer
to all models in the SG Series hot dog grills. The SG-18
model will vary slightly due to having only one motor,
but the parts replace instructions remain essentially the
same. The right and left side of the unit is determined
by facing the front (control switch) side of the grill. The
left side switch controls the front 5 (#1 thru #5) rollers
on the grill. The right side switch controls the rear 5 (#6
thru #10) rollers.
A Panel Removal:
1. All parts replacement procedures will require the
removal of one or both side panels and/or the
bottom panel.
2. To remove either side panel; remove the 8 sheet
metal screws.
3. To remove the bottom panel; tilt the grill up from the
front and rest on the back of the unit. Remove the 6
sheet metal screws. (SG-34 model has 10 screws)
B Control Switch Replacement:
(Figure 1, 4 & 5)
1. Remove bottom panel. (Section A)
2. Remove the 2 slotted screws and spacers securing
the switch to the front panel. Note proper orienta-
tion of spacers.
3. Disconnect wire leads from switch terminals.
4. Remove switch from underside of unit.
5. Insert new switch from underside of unit and secure
with the 2 slotted screws and spacers.
6. Re-attach wire leads to switch terminals. (Refer to
appropriate wiring diagram)
C Power Indicator Light Replace-
ment:
(Figure 1, 4 & 5)
1. Remove bottom panel. (Section A)
2. Disconnect the wire leads from back of light.
3. Press spring loaded tabs on back of light and push
through front of panel.
4. Insert new light from front of unit and snap into place.
5. Re-attach wire leads to light terminals. (Refer to
appropriate wiring diagram)
D Terminal Block Replacement:
(Figure 4 & 5)
1. Remove bottom panel and appropriate side panel.
(Section A)
2. Remove the 2 screws and nuts securing the terminal
block to the unit.
3. Disconnect wire leads from terminal block, noting
properorientation.
4. Secure new terminal block to unit with the 2 screws and
nuts.
5. Re-attach wire leads to terminal block. (Refer to
appropriate wiring diagram)
E Motor & Motor Sprocket Replace-
ment:
(Figure 2, 3, 4 & 4)
1. Remove bottom panel and appropriate side panel.
(Section A)
2. Loosen the 4 motor mounting nuts securing the motor
to the unit and slide motor to loosen drive chain tension.
Slip drive chain off motor sprocket (and idler sprocket
on SG-18 models).
3. Disconnect wire leads from motor terminals.
4. Remove the loosened motor mounting nuts and remove
motor.
5. Before installing new motor, transfer the motor fan and
sprocket from the old motor to the ne motor. Note
proper orientation of fan blades. To remove the
motor sprocket from the motor shaft, loosen the set
screw in the sprocket with an Allen wrench, and slip
sprocket off shaft. Note proper orientation of set
screws (on the flat portion of the motor shaft) and
the sprocket.
6. Secure new motor (with fan and sprocket in place) to
unit with the 4 motor mounting nuts. Do NOT tighten
nuts.
7. Place drive chain around motor sprocket (and over idler
sprocket on SG-18 models).
8. Slide motor to tighten drive chain tension and tighten
the 4 motor mounting nuts.
9. Re-attach wire leads to motor terminals. (Refer to
appropriate wiring diagrams)

ELECTRICAL SPECIFICATIONS
F Idler Sprocket/Idler Sprocket
Screw Replacement: (For SG-
18 models only)
(Figure 3 & 4)
1. Remove bottom panel and side panel.
(Section A)
2. Remove nut and lock washer and screw
securing idler sprocket to unit. Note
location of spacer behind idler sprocket.
3. When installing new idler sprocket insert
screw from underside of unit. Replace
spacer, sprocket, lock washer and nut from
motor side.
4. NOTE: When replacing idler sprocket on
idler sprocket screw, be sure that the
sprocket teeth are properly seated in drive
chain.
5. Tighten idler sprocket screw and nut.
G Power Cord Replacement:
(Figure 4 & 5)
1. Remove bottom panel. (Section A)
2. Disconnect the green ground wire from the
unit.
3. Disconnect the 2 wire nuts.
4. Remove the strain relief bushing with plyers.
Note proper orientation of flat and round
sides of the strain relief bushing.
5. Reverse this procedure to install new power
cord. (Refer to appropriate wiring diagram)
H Individual Heating Element
Replacement:
(Figure 2 & 3)
1. Remove both side panels. (Section A)
2. ON SG-18 MODELS: When replacing
elements on this unit, remove the appropri-
ate 5-way jumper weldment.
ON SG-22/SG-34 MODELS: When replac-
ing element #1, 3, 5, 6, 8 or 10, remove the
appropriate 3-way jumper.
ON SG-22/SG-34 MODELS: When
replacing element #2, 4, 7 or 9, remove
the appropriate 2-way jumper.
IMPORTANT: NOTE PROPER ORIEN-
TATION OF WIRE LEADS AND POSI-
TION OF JUMPERS.
3. On opposite end of element you are
replacing, remove the screw securing it
to the 5-way jumper.
DO NOT REMOVE THE 5-WAY
JUMPER.
4. Slide element out of roller from the motor
side of the unit.
5. Insert new element, making sure that the
element terminal ends are in proper
position.
6. Secure opposite end of element to 5-way
jumper.
7. Replace appropriate jumper on motor
side of unit.
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MODEL VOLTAGE AMPS KW
SG-18 120V 8.3 1.0
SG-22 120V 10.0 1.2
SG-34 120V 14.1 1.7
I DRIVE CHAIN REPLACEMENT
(Figure 2 & 3)
1. Remove appropriate side panel. (Section A)
2. Loosen (but do not remove) the 4 motor mounting nuts.
3. Slide motor to loosen drive chain tension and slip chain
off motor sprocket (and idler sprocket on SG-18 mod-
els).
4. Remove all jumpers on motor side of unit. (Note orienta-
tion of wire leads and proper positioning of jumpers).
5. Remove the 2 nuts and washers from the weld studs
that secure the drive chain guide to the unit and remove
the guide. (There are 2 chain guides on the SG-18
models).
6. Remove the drive chain.
7. When placing the new drive chain over the roller sprock-
ets, make sure it lies flat and rests on each tooth of the
roller sprockets.
8. Replace the drive chain guide(s), making sure element
terminal ends are positioned properly and guide is
properly seated.
9. Re-position drive chain around motor sprocket (and idler
sprocket on SG-18 models). Slide motor to tighten drive
chain tension and tighten the 4 motor mounting nuts.

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J Roller Replacement
(Figure 1, 2 & 3)
1. Remove the appropriate side panel. (Section
A)
2. Remove appropriate drive chain. (Section I)
3. Remove the appropriate roller retainer bar
(IMPORTANT: Note proper positioning on
the 4 washers (2 on each stud) located
between the roller retainer bar and the wall of
the unit. These washers MUST be installed
in this position to achieve proper roller
rotation).
4. While holding element terminal upwards to
achieve clearance, slide out roller.
5. NOTE: At this stage of replacement, it is
suggested that the teflon bushings be
inspected for possible wear and replaced if
necessary. (section K)
6. Insert new roller, holding element terminal
end upwards to achieve clearance.
7. Replace roller retainer bar making sure to
place the 2 washers on each weld stud
before replacing retainer bar.
8. Replace drive chain. (Section I)
K Teflon Bushing Replacement
(Figure 1, 2 & 3)
1. Remove appropriate side panel. (Section A)
2. Remove appropriate heating element. (Section
H)
3. Remove appropriate drive chain. (Section I)
4. Remove appropriate roller. (Section J)
5. Working from inside (Motor) side of unit, push
out bushing (Towards cooking surface of rollers)
with a screw driver.
6. New bushings MUST be installed from the
cooking surface side, towards the inside of the
side panel. Be sure the flattened slot on the
bushing is correctly positioned in opening.
7. Replace roller. (Section J)
8. Replace drive chain. (Section I)
9. Replace heating element. (Section H)
ELECTRONIC SPECIFICATIONS FOR 208V/240V MODELS