Lincoln 1633-000-EA Service Manual

SERVICE MANUAL

(INTERNATIONAL)

IMPINGER CONVEYOR OVENS

LOW PROFILE 1600 INTERNATIONAL ADVANTAGE

Lincoln Foodservice Products, LLC

1111 North Hadley Road

Fort Wayne, Indiana 46804

United States of America

Phone: [phone]

U.S. Fax: [phone] • Int’l Fax: [phone]

Technical Service Hot Line

[phone]

www.lincolnfp.com

1600expadv REV: 1/8/07

SERVICE AND PARTS MANUAL

1600 INTERNATIONAL ADVANTAGE

SEQUENCE OF OPERATIONS ..............................................................................................3

SCHEMATIC............................................................................................................................ 5

TROUBLESHOOTING GUIDE ................................................................................................ 6

REMOVAL, INSTALLATION & ADJUSTMENTS................................................................. 12

GENERAL PARTS................................................................................................................. 20

ADVANTAGE SERIES..........................................................................................................20

CONTROL BOX, RIGHT PARTS...........................................................................................22

CONTROL BOX, LEFT PARTS............................................................................................. 24

OVEN BACK PARTS .............................................................................................................26

CONVEYOR PARTS ............................................................................................................. 28

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Low Profile – 1600 Advantage Series Service Manual – International

SEQUENCE OF OPERATIONS

MODEL 1633-000-EA 230 VAC 50HZ NATURAL GAS
MODEL 1634-000-EA 230 VAC 50HZ L.P. GAS

POWER SUPPLY
Electrical power to be supplied to the oven by a three conductor service.

Brown conductor is hot
Blue conductor is neutral.
Green conductor is ground.

CONTROL BOX
AUTO COOL DOWN

When the temperature in either one of the control boxes reaches 120°F ±3° (49°C ± 1.7° ) , the cooling fan
thermostats will switch power to the cooling fans . The thermostats will interrupt power to the cooling fans when
the temperature falls to 100°F ± 3° (37°C ± 1.7° )

MAIN FAN CIRCUIT

Line voltage is permanently supplied to a normally open contact of the oven power switch. Line voltage is
permanently supplied to the two normally open cooling fan thermostats, a normally open contact of the oven
power relay. Closing the oven power switch supplies line voltage to oven power relay, its contacts now close,
supplying line voltage to the two main fan motors and the two burner circuits. Closing the oven power switch also
supplies line voltage to the control box cooling fans, the temp. display, and the conveyor circuit.

BURNER CIRCUIT

NOTE: This oven utilizes two complete burner/ temperature control systems. The sequence of operations is the
same for each system.
Closing the main fan switch supplies line voltage, through the oven power relay, through a three amp. fuse,
through the gas pressure switch, through the main fan air pressure switch through the oven cavity hi-limit
thermostat, to the ignition control. The combustion motor is energized. The normally open combustion air switch
closes upon sensing air pressure. After a pre-purge period of between 30 and 60 seconds, the ignition
transformer and the main gas valve are energized. Ignition should now occur.

TEMPERATURE CONTROL

Closing the oven power switch supplies line voltage, through the oven power relay, through a three amp. fuse,
through the gas pressure switch, through the main fan air pressure switch through the oven cavity hi-limit
thermostat, to the temperature control board. The 1.0K temperature pot. is adjusted to desired temperature. The
thermocouple will provide varying millivolts to the temperature control. The temperature control supplies line
voltage to the solenoid valve at intermittent intervals to maintain desired temperature.

CONVEYOR DRIVE

Closing the oven power switch supplies line voltage, through the oven power relay, through the electromagnetic
filter to the conveyor control. AC volts are converted to DC volts and are supplied to the conveyor motor at
terminals A+ and A-.

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Adjustments of the speed control potentiometer will change resistance at terminals P1 and P2 varying the DC
voltage to the motor. The speed of the conveyor motor will increase or decrease as the DC voltage from the board
increases or decreases respectively.

NOTE: The conveyor control uses a sensor and magnet, mounted on the conveyor motor that senses motor
speed. Any change in motor load ( ± RPM ) is detected by the sensor and the voltage to the motor is adjusted
accordingly.

TEMPERATURE DISPLAY

Closing the power switch supplies line voltage to the primary of the temperature display transformer. The
secondary of this transformer supplies 12 VAC to the temperature display. The thermocouple supplies DC
millivolts to the temperature display. The display converts this millivolt reading to a temperature reading.

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Low Profile – 1600 Advantage Series Service Manual – International

SCHEMATIC MODELS 1633-000-EA AND 1634-000-EA

Low Profile – 1600 Advantage Series Service Manual – International

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TROUBLESHOOTING GUIDE

MODEL 1633-000 EA NATURAL GAS 230 VAC 50 HZ 1 PHASE
MODEL 1634-000-EA L.P. GAS 230 VAC 50 HZ 1 PHASE

NOTE: When checking components on left side of unit, be sure to check for proper
connections in power connector, ( marked P. C. on schematic diagram ) located inside
motor cover.

SYMPTOM POSSIBLE CAUSE EVALUATION

Oven fan will Incoming power supply Check breakers/ reset if required
not run call Power company if needed
Oven fan switch Check continuity between
switch terminals.
Thermostat, hi-limit Terminals are normally closed, if
open, reset thermostat and test
oven for proper operation. If it
will not reset, replace thermostat.
Fan fuse Check, replace if necessary.
Fuse holder Check, replace if necessary.
Oven fan relay Check for power to coil of oven
fan relay. If no voltage is present,
trace wiring back to hi-limit thermostat.
Check for supply voltage at terminal
#6 of the relay. If no voltage is present,
trace wiring back to fuse holder. If
voltage is present, at the relay coil, check
to insure the contacts are closing.
Capacitor(s) Check for opens, shorts, or grounds.
Motor (s) Check for opens, shorts, or grounds.
No control box cooling Fan switch (SEE OVEN
Hi-limit FAN WILL
Oven fan relay NOT RUN.)
Cooling fan(s) Supply voltage should now be at these
motors. If voltage is present, check
motor for open, shorts, or grounds.
WITH POWER OFF: check for
locked rotor.
No automatic control Incoming power supply Check circuit breakers, reset if needed.
box cooling Call power company if needed.
Cooling fan thermostats Thermostat closes at 120°F and
opens at 100°F. With the cooling
fan thermostat preheated, check
for continuity. If switch is open, replace.
Cooling fan(s) Supply voltage should now be at these
motors. If voltage is present, check
motor for opens, shorts or grounds.
WITH POWER OFF: Check for
locked rotor.

Oven will not heat Gas supply Check for adequate gas supply to oven.
Manual gas shut off valve Check to see that the manual gas shut
off valve is open.
Fan switch Check to see that the fan switch is on.
Main oven fan Check if main oven fan is operating.
if not, refer to “oven fan will not run”.
NOTE: These ovens utilize 2 complete Burner/Temperature control systems. Each system will
Follow the same troubleshooting sequence.
Fuse, burner 3A. Check, replace if necessary.

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Low Profile – 1600 Advantage Series Service Manual – International

Fuse holder Check, replace if necessary.
Gas pressure switch Check for supply voltage to neutral
(internal to gas valve) on both sides of switch. If voltage is
present on one side of switch only,
check the following. Check for proper
gas pressure supply to gas valve.(Marked
on oven spec. plate.) Check for proper
adjustment of gas pressure switch.
should be set at 10 Nat., 27 for L.P.
or 4.5 for town gas. Check gas filter in
gas valve for blockage or damage. (See
Adjustment section for location.)
If the above checks OK, but switch is
still not closed replace gas valve.
Oven air pressure switch Check for supply voltage on both sides
of switch. If voltage is present on one
side only, check for air tube blockage.
Adjust air pressure switch. If the above

fails, replace air pressure switch.
Hi-limit thermostat Terminals are normally closed. If open,
reset and test oven for proper operation.
If thermostat will not hold for maximum
oven temperature, and oven is not
exceeding maximum temperature dial
setting, check for proper location of
capillary bulb in its spring holder.
If above checks OK, replace hi-limit.
Ignition control Check for supply voltage to ignition
control at terminal #1 and neutral.
If voltage is not present, trace wiring
back to hi-limit thermostat. Check for
supply voltage at terminal #6 to neutral.
If no voltage is present, wait 30 seconds
and check reset button. If above fails,
replace ignition control.
Burner reset switch Switch is normally open. Check to see
that the switch closes when reset button
is pushed. Replace as needed.
Burner blower motor Check for supply voltage to burner
blower motor.
WITH POWER OFF: Turn blower
wheel to check for locked rotor. If
supply voltage is present and motor does
not run, replace motor.
Burner blower motor Check for supply voltage switching to
Air pressure switch terminal N. O. as the air pressure switch
closes. Check for air tube blockage or
misalignment, adjust air pressure switch.
If the above fails, replace air pressure
switch.
Spark generator After a pre-purge time of 30 to 60
seconds after blower motor starts,
check for supply voltage to spark
generator. If voltage is not present,
Check reset button located on rear of
control box. If voltage is still not
present, replace ignition control.
If voltage is present, visually check
for spark at igniter head.
Igniter/sensor assembly Check for visible damage to igniter/
sensor assembly. If there is no visible
damage to the components, and no spark,

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replace the spark generator. If there
is visible damage to the igniter/sensor
assembly, replace. Also check for frayed
or damaged wires in burner tube.
Gas valve Check for supply voltage to gas valve.
If there is no voltage present, check
reset button, check all connections for
tightness. If there still is no voltage at
gas valve, replace ignition control.
If there is voltage present, check for
gas pressure at gas pressure tap located
in gas piping at burner manifold.
If there is no gas pressure, replace
gas valve.
Flame will not stay on Flame sensor To check for flame sensor operation,
connect a digital multimeter (capable
of measuring D.C. micro amps) in
series with the flame sensor wire and
ignition control. Sensor current is 3
micro amps D.C. minimum.
NOTE: The D.C. micro amp test must
be conducted with the oven in low
flame (bypass) operation. Turn the
temperature control to its lowest
setting. If these readings are not
achieved, replace igniter/sensor assy.
Also, check for any type of damage to
flame sensor wire and connections.
Ignition control If there is sufficient flame sensor current,
but the burner will not remain ignited,
check the reset button on ignition control.
NOTE: Check for proper polarity of
the power supply. If all of the above
are OK, replace ignition control.
Pilot lamp is on, Temperature control Check for supply voltage across
But no main flame terminals L2 and 240 on temperature
control board. If no voltage is present,
check wiring back to hi-limit thermostat.
Turn the temperature adjustment knob to
the maximum temperature position and
check for supply voltage at the load
terminal #7 and #8. If voltage is present
and unit is not heating, refer to
“temperature regulation valve” for next
check. If voltage is not present, proceed.
Thermocouple probe With power on and thermocouple leads
attached to board, measure the millivolt
out put of the thermocouple. Refer to the
thermocouple chart in section D for
proper readings.
Temperature control WITH POWER OFF: Remove the
Potentiometer potentiometer leads from the temperature
control board. Place ohm meter test leads
on the blue and green pot leads. Reading
should be 1 K ohms. Place meter leads
across the blue and purple pot leads and
rotate knob from high to low. Repeat on
green and purple leads. Check for even
rise and fall of ohms reading to insure
that there are no open or dead spots in
the potentiometer. Check each lead to
ground for shorts. Replace potentiometer

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Low Profile – 1600 Advantage Series Service Manual – International

as needed.
Temperature regulation If supply voltage is present on the
valve temperature control board at the load
terminals #7 and #8, check for voltage
at temperature regulation valve. If
voltage is present, listen for valve to
open and close. Also, check for opens
or shorts in the coil. Replace if required.
Intermittent heating Thermal overload of The main fan motors and the burner
main fan and burner blower motors are equipped with
blower motors internal thermal protection and will
cease to operate if overheating occurs.
As the motors overheat and then cool,
this will cause the units to cycle on
and off intermittently. This may be
caused by improper ventilation or lack
of preventive maintenance. Also, most
of the problems listed under “Oven
will not heat” can cause intermittent
failure.
Conveyor will not run Power supply Check for supply voltage at terminals
L1 and L2. If voltage is not present,
check breakers.
Fan switch See procedure for checking on page 6.
Fuse, 10 Amp. Check and/or replace.
Fuse holder Check and/or replace.
Filter E.M.I. Check for supply voltage input to
filter. If there is no voltage, trace wiring
back to relay. If there is input voltage,
check for output voltage. If there is
input voltage but no output voltage,
replace filter.

Speed adjustment This is a 0 to 10K ohm, 1 turn
potentiometer potentiometer. With power off, remove
the black and white pot leads from the
conveyor control board at terminals
P1 and P2. Place the meter leads on
black lead (P2) and the white lead (P1).
Rotating the pot. slowly, from low to
high, the meter reading should show
an even transition from 0 to 10K ohms
± 5%. There should be no dead or open
spots through the one turn of the pot.
Check both leads to ground. There
should be no continuity to ground.
If any of the above fail, replace
the potentiometer.
D.C. motor Check for supply voltage input to
control board the control board at terminals L1 and L2
If not present, check wiring back to
the filter. If supply voltage is present,
check both fuses on the control board
( 8 Amp. line and 1Amp. armature).
Check the D.C. voltage output at
terminals A+ and A-. If A.C. voltage
is at terminals L1 and L2, and no
D.C. voltage is present at A+ and A-,

replace control board. If A.C. voltage is
present and D.C. voltage is present but
the motor will not run, check gear motor
as follows:

Conveyor If D.C. voltage is present at A+ and A-

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gear motor and the motor does not run, first check
the mini breaker and then the conveyor.
Refer to the next possible cause. Check
the leads to the motor for evidence of
any shorts or opens , and each lead to
ground. Check motor brushes . From
the top of the motor, rotate motor shaft
to determine if there is a locked rotor
or a locked gearbox (use care so magnet
and Hall Effect sensor board are not
damaged). Replace motor as needed.
Conveyor Check for any mechanical misalignment.
Also, check for worn bearings.
A conveyor belt that is over tightened
will cause excessive bearing wear and
sometimes, irregular speed.
Conveyor speed varying Power supply Check power supply at the D.C. control
or intermittent board for supply voltage at board terminals
L1 and L2.
Motor control board Place the test meter probes on terminals
A+ and A-. (with speed potentiometer
set to maximum speed – approximately
2 min.). The meter reading should be
approximately 100VDC(±3%), if
voltage is not steady within limits,
then the board is usually bad.
Always check the speed potentiometer,
be sure it is OK before changing a
control board. This test is not always
100% accurate as this test is not
performed at operating speeds, However,
this test is the best method currently
available.
D.C. Gearmotor If the D.C. control board is steady,
then the problem may be the motor or
gearbox. Check the brushes in the
motor for excessive arching or
unusual wear. Check the motor and
gearbox from instructions located on
page 9 under “possible cause”
listing “conveyor gear motor”
Magnet Check to insure that the magnet
(cemented to shaft of conveyor drive
motor) has not been damaged, or come
loose from the motor shaft. Replace
as needed.
Hall Effect Check for any physical damage to
Sensor hall effect sensor (mounted on
conveyor drive motor). Check all
wiring and connections for tightness
and proper location. Replace as needed.
Connect new hall effect to system
and check for steady operation.
Temperature display Display transformer Measure the transformer primary
inoperative for supply voltage input. If voltage is
not present, trace wiring back to the
fan relay. If voltage is present,
measure the secondary output of the
transformer. Voltage across terminals
1-3 should be 12-15VAC. Terminals
1-2 and 2-3 should be ½ the voltage
reading from terminals 1-3. If the above

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Low Profile – 1600 Advantage Series Service Manual – International