Questt Signage400H User manual

Wuhan Questt Asia Technology Co., Ltd
Address: A7-101, Hangyu building, Wuhan University Sci & Tech Park, East Lake High-tech Dev. Zone, Wuhan, Hubei, China
Tel/Fax: [phone] http://www.questt.com.cn Email:[e-mail]
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Operation Manual
Laser Welding Machine
Signage400H
Wuhan QUESTT ASIA Technology Co., Ltd
Address: A7-101, Hangyu building, Wuhan University Sci & Tech Park, East Lake High-tech Dev. Zone,
Wuhan, Hubei, China
Tel: [phone] Fax: [phone]
http://www.questt.com.cn http: //www.questtlaser.com
Contents

Wuhan Questt Asia Technology Co., Ltd
Address: A7-101, Hangyu building, Wuhan University Sci & Tech Park, East Lake High-tech Dev. Zone, Wuhan, Hubei, China
Tel/Fax: [phone] http://www.questt.com.cn Email:[e-mail]
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Chapter 1 Machine Introduction
1-1 Prospect of AD metal letters/signage welding industry
1-2 Application
1-3 Features
Chapter 2 Machine main parts and operation instruction
2-1 Machine preview
2-2 Hardware installation
2-3 Machine operation
2-4 Parameters & specifications
2-5 Control Panel
Chapter 3 Technical index
3-1 Laser
3-2 Technical parameters
3-3 Welding point size
3-4 Optics system
3-5 Cooling system
3-6 Power supply
3-7 Working environment and continuous operation time
Chapter 4 Overall structures and maintenance
4-1 Laser
4-2 Laser Power supply
4-3 Optical system
4-4 Cooling system
Chapter 5 Appendix
5-1 Welding operations
5-2 Specialties
5-3 Typical applications
Chapter 6 After-Sale Service
Chapter 1 Machine Introduction

Wuhan Questt Asia Technology Co., Ltd
Address: A7-101, Hangyu building, Wuhan University Sci & Tech Park, East Lake High-tech Dev. Zone, Wuhan, Hubei, China
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1-1 Prospect of AD metal letters/signage welding industry:
With the booming of global advertising industry, metal letters has been more and more
popular because of its colorfulness, attractiveness, heating-proof, frozen-proof, no
deformation, no fadedness (8-10 years color preservation), corrosion proof, rain-proof, and
spontaneous combustion proof and some other good features. AD metal letters are made of
stainless steel, aluminum, copper or other metal sheet being cut, polished, hemmed, and
welded. The core feature of AD metal letters is being rustproof, with long life span and
dimensional looks. It’s widely used in LED illuminated billboard, exterior/interior signs,
branding, door plate and etc.
Regular combination and fixing of metal letters are done via glue, rivets or soldering, but all
of them have big defects. Metal letters combined by glue always get loose with time goes by,
especially at outdoors. Fixing by rivets sounds good, but not good-looking. Soldering is
never a green way of fixing metal letters because of the poisoning gas produced when
processing.
However, laser welding technology makes two metal sheets become one only by a few
melting spots. From any aspect, laser welding is the best solution and the greenest.
1-2 Application:
Applied for the welding of various metal letters, LED illuminated letters, customized metal
signage, and exterior billboards.
1-3 Features:
1. Red light fast positioning, CCD display, microscope optional
2. Adjustable working table allows welding from small size to big size of work piece
3. Fast working speed; professional jig ensures the focus fixed and makes welding
easier without using CCD or microscope
4. Slight distortion and affect by heating.
5. Capable of partial heating process.
6. Able to deal with complex, profiled, or tiny letters.
7. Low noise and no pollution.
8. Ultrafine positioning rod makes the welding of tiny corner easier without changing
spot position
9. New metal processing technology brings higher quality of end products.
Chapter 2 Machine main parts and operation instruction

Wuhan Questt Asia Technology Co., Ltd
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2-1 Machine preview:
Attention:
1. The laser system requires 380V 50HZ power supply. Water cooling system requires 220V
50HZ power. Any damage caused by misconnect is not obliged by seller.
2. Current ranges from 60-200A, and pulse ranges from 1ms -5ms. The frequency is 4Hz for
spot welding and 20Hz (or above) for continuous welding.
3. Make the laser chamber up and down by twisting the wheel-bar until you find the beam
lightest, roundest and sounds loudest. That means the best laser is ready with correct focal
length. To avoid penetration of material, you may decrease the current or enlarge the
facula to weaken single power.
4. Do not energize equipment before installation to avoid electric shock or other dangerous
accidents.
5. The standard protection mat is plastic. When it’s worn out, glass plate of exactly same size
with the table would be recommended.
6. The water inside the chiller has to be replaced once a month. Deionized water is preferable,
but drinking water is also fine.
2-2 Hardware installation:

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1) Link one water tube to “OUTLET”, and another to “INLET”, then fix the bolts tight.(A and A
or B and B for one group),full fill the water tank .
2) Connect all the cables in Power Supply box , Flow Alarm at the back of master and foot
switch
3) Power Line

Wuhan Questt Asia Technology Co., Ltd
Address: A7-101, Hangyu building, Wuhan University Sci & Tech Park, East Lake High-tech Dev. Zone, Wuhan, Hubei, China
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Wuhan Questt Asia Technology Co., Ltd
Address: A7-101, Hangyu building, Wuhan University Sci & Tech Park, East Lake High-tech Dev. Zone, Wuhan, Hubei, China
Tel/Fax: [phone] http://www.questt.com.cn Email:[e-mail]
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Two groups of line as shown on access，Two sets of lines without position requirements
4) Adjust laser cavity to the most suitable place and tighten the four screws
5) Red light locator switch

Wuhan Questt Asia Technology Co., Ltd
Address: A7-101, Hangyu building, Wuhan University Sci & Tech Park, East Lake High-tech Dev. Zone, Wuhan, Hubei, China
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6) Connection of CCD and laser head
The laser system requires 380V 60HZ power supply. Water cooling system requires 220V
60HZ power.
Attention: It requires 6 square mm wires, and 60A air switch.
7) Twist the two knobs to make fine tuning of laser head’s horizontal position

Wuhan Questt Asia Technology Co., Ltd
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8) Twist the wheel handle to adjust the vertical position of laser head
9) Press the wall tape and cover tape together with your finger, pull them back against
positioning rod, make sure the red dot is just on the seam to be welded, then trigger the
laser with foot pedal.
10) For fiber laser gun, turn to Fiber Mode first, press the red button with your finger, then
the laser beam will come out.

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2-3 Machine operation
A. Turn on the machine
1. Turn on air switch
2. Turn on the water chiller switch (Attention: Set the water temperature no more than 30
Celsius degree.)
3. Pull and twist emergency stop button
4. Turn on key switch
5. System initializing, press OK when it reads OPEN in left-top corner of screen.
6. After the lamp is turned on for 90 seconds, you can hear the sound when the relay of the
machine casing is closed and a sound of “beep” from the buzzer, which means the laser
lamp, is lightened. The word “Close” will appear in the left-top corner, which means the
machine is working normally. And you may adjust the parameters now.
B. Turn off the machine
1. Move cursor to CLOSE, and then press OK. The word “Close” will be displayed. A sound
will be heard when the relay in the machine casing is disconnected.
2. Turn the KEY switch counter-clockwise to OFF position;
3. Turn off Emergency Stop
4. Turn off water chiller after 1 minute wait
5. Shut off General Power supply.
2-4 Parameter specifications:
Current: Laser current value
Regulate range: 50A ~600A
Pulse: Single laser release time
Adjusting range: 0.1ms~15ms
Frequency: Welding times per second
Adjusting range: 0.5Hz ~ 50Hz

Wuhan Questt Asia Technology Co., Ltd
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Facula: Positive and negative defocus from 0.1~3.0mm
Attention: This option is locked. Please adjust facula by turning the grey knob on the other end
of laser cavity.
2-5 Control Panel
Precautions:
Please read instructions carefully before starting up the Laser Welding Machine.
Operation instructions
The two Select buttons are used for selecting the menu on the screen; the change of the
parameters is controlled by the Adjust button on the panel. When the cursor is moved to the
corresponding place, the related button can be pressed to set the required parameters.
Width:
It displays the pulse width of the laser discharging per millisecond, minimum value 0.1 and
maximum value 20. The wider the pulse width is, if the working voltage is the same, the
higher output energy of laser will be. Press the Up/Down key on the control panel for one
time, the pulse width of laser discharging will be increased or decreased by 0.1 millisecond.
Frequency:
It displays the frequency of laser discharging, with the unit of HZ. The higher the frequency is,
more times laser will shoot in unit time. Press the Up/Down key on the control panel for one
time, the pulse width of laser discharging will be increased or decreased by 1HZ.
Light shielding:
When the pedal switch is closed and the word “laser” is displayed in the screen, the liquid
crystal light valve can shield the flashing light. Under non-work conditions, the word “laser”
won’t be displayed.
Working current:
It displays the discharging current for the laser. When the pulse width is identical, the higher
the working voltage is, the higher laser output energy will be. Press the Up/Down key on the
control panel for one time, the discharging current for the laser can be increased or
decreased by 1A, ranging from 50—600A.
Chapter 3 Technical index

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Address: A7-101, Hangyu building, Wuhan University Sci & Tech Park, East Lake High-tech Dev. Zone, Wuhan, Hubei, China
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3-1 Laser:
Working material: ф8 *145mm，Nd3+：YAG
Wavelength: 1064um
Pulse xenon lamp: ф8*270
Pulse frequency: 0~20ms, gradational adjustable
Max single pulse energy: 100 joule
Max. laser power: 400W
3-2Technical parameters
Model
400W
Laser working substance
Nd3+：YAG Crystal &ceramic resonance cavity
Max. single-pulse energy
100J
Max. peak power
14KW
Laser wavelength
1064nm
Focal facula diameter
ф0.10-3.0mm adjustable
Rated output power
400W
Min. molten pool
0.3mm
Pulse width
0.5ms-15ms adjustable
Pulse depth
≤3mm
Pulse frequency
1-50HZ adjustable
Observing system
CCD
Weight
319Kg
3-3 Welding point size:
Diameter: 0.1~3mm, adjustable
3-4Optics system:
Extending ratio: 4 times
Focus-length of lens: 170mm
3-5 Cooling system
The equipment employs water cooling system in which the magnetic pump drives the
circulating water to cool the laser crystal and pumping lamp, with overheat and overflow
protection. The deionized water with resistance rate more than 0.5MΩ-cm is used as the
circulating water, 4 liters for each time. The circulating heat is taken away by the refrigerating
machine and finally discharged into the outside atmosphere by the fan.

Wuhan Questt Asia Technology Co., Ltd
Address: A7-101, Hangyu building, Wuhan University Sci & Tech Park, East Lake High-tech Dev. Zone, Wuhan, Hubei, China
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3-6 Power supply: single phase AC 380V±10%，water chiller 220V±10%,50Hz
3-7 Working environment and continuous operation time
Working environment should be clean, oily fog and dust free, far from violent vibration, with
operating temperature 10℃-32℃and humidity≦90%. Continuous operation time for the
whole machine can be more than 8 hours.
Chapter 4 Overall structures and maintenance
The integral machine is composed of five parts, namely, the control cabinet, cooling system,
power cabinet, laser and optics processing system.
The equipment can also be divided into five parts in terms of functions, which are:
1) Laser;
2) Laser power supply;
3) Optics system;
4) Controlling system;
5) Cooling system.
4-1 Laser
(1) Structure
The laser is a device that converts the electrical energy into the laser energy. This machine
employs Nd3+：YAG Laser, consisting of the following parts:
a) Pumping lamp: it converts the electrical energy into the optical energy that can activate
the substances for laser processing. The machine adopts pulse xenon lamp with repetition
rate of XMC7-125. Both the electrode and quartz glass tube surface need to be cooled
during working.
b) Laser crystal: it converts the optical energy into the laser energy. This machine
employs the crystal ф8*145mm Nd3+: YAG as its working substance.
c) Condensing cavity: it focuses the light from the pumping lamp onto the working
materials.
d) The optical resonant cavity can provide optical feedback, allowing the laser to be
magnified to form high strength laser for output. This machine employs the plane and
parallel cavity made up of flat mirrors with ceramics as its medium. The full reflector’s
transmissivity is less than 0.4%, output reflecting mirror’s transmissivity is 85%.
e) Other parts: high voltage electrode, insulation base plate, positioning bracket, adjustable
diaphragm frame and laser holder.

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(2) Precautions and maintenance
As the machine is highly precise equipment whose discharging features the high pulse
voltage and charging features the large capacity, and the laser focusing energy is highly
centralized, the operators must obtain professional knowledge and skills before they work on
the machine.
A. Optical resonant cavity
The two medium diaphragms of optical resonant cavity are absolutely parallel to the laser
bar’s end face, touching or random adjustment is not allowed. Do not open the outer hood of
the laser randomly and keep the optics surface highly clean. Otherwise, the high-energy
laser will damage the diaphragm layer. When the laser output energy is lowered down, the
operator should first check whether the medium diaphragm is clean. If any dirt, he can use
lens paper or cotton wool moistened by the cleaning agent (liquid mixture with ethanol
absolute and ethanol respectively occupying 50%, the same when mentioned in the
following part) to clean it gently. Then check the resonant cavity to see if it is misadjusted.
B. Cooling system
The laser has one water inlet pipe and one outlet pipe, respectively connected to the cooling
channels of the lamp and bar. Unsmooth water flow at any part will cause large loss. Each
time when the equipment is assembled, the operator should check the water flow at each
path and make sure no fault exists before starting up the laser.
C. Xenon lamp replacement
The average service time of the pulse xenon lamp is 108 times of blinking if it works under its
rated power and belongs to the consumptive pieces. To ensure the normal performance of
the machine, the lamp must be replaced when it has reached its rated blinking times (about
108 times) and the energy becomes low.
In cases that the xenon lamp is damaged or its service time is shorted due to other causes
(for example, it can’t pre-illuminate or no energy output is available when the voltage is
increased to 500V), the xenon lamp should also be replaced.
As the strength of the sealing at the lamp’s two ends is relatively low and apt to being
damaged, special caution should be offered when substituting the lamp. The following
procedures should be followed:
a. Turn off the machine, cut off the water supply and discharge the remaining electricity on
the energy-storage capacitor;
b. Remove the electrodes of lamp;
c. Remove the gland of lamp, carefully pull out the lamp from the side of the full reflector;
d. Use cotton moistened by cleaning agent to clean the sleeving;
e. Check to see if the appearance, size and other aspects of the new lamp is conforming;
f. Install the new lamp into the chamber, press the gland tight and mount the electrodes;
g. Connect to the water supply and check the sealing of each part to see if they are reliable;
h. Turn on the main power to check whether the lamp can discharge normally;

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i. Try single spot operation, check whether the output energy of laser meet the
requirements. If the output is not ideal, repeatedly adjust the resonant cavity;
j. Cover the laser with outer hood.
D.Nd3+：YAG crystal is the core part of the laser, and is fairly expensive. Therefore it should
be installed with great care. The two end faces of Nd3+：YAG crystal bar is absolutely parallel
to each other and has high cleanliness. If there is any pollutant on the end faces, the
luminous efficiency will be lower, the facula mode will deteriorate, or even can’t illuminate
normally. In that case, the space housing this machine must be cleaned and professionals
should be called for related treatment. Take out the Nd3+：YAG crystal bar, use lens paper or
absorbent cotton moistened by cleaning agent (liquid mixture with ethanol solution and
another respectively occupying 50 %,) to remove the dirt gently. The causes leading to the
damage of crystal bar can be described as follows:
a.The flow of cooling water is over or interrupted, the energy input into the lamp makes the
lamp and bar overheated, which results in the cracking of the lamp and bar;
b.The end face is bumped, scratched or even damaged by hard object;
c.As the diaphragm layer is polluted , the bar is damaged when the high strength laser
passes by;
d.The bar is pressed too tightly or the applied force is uneven when it is installed, the over
high interior stress breaks the bar. In this case, the operator should not open the hood of the
laser, nor operate the YAG bar. If the end face is found polluted, professionals should be
called for the related treatment.
E.The condensing cavity doesn’t need maintenance work. Normally, it is not allowed to
dismantle the condensing cavity.
F. Over voltage protection
There are three kinds of voltage applied to the pulse xenon lamp in succession, namely, trigger
voltage about 13-18 kv, pre-burning open-circuit voltage 1500-1800 v and arc-discharge
voltage about 500-2500 v. Therefore, the lamp electrode should not get too close to other
metal objects, and a distance of more than 15mm should be kept. The insulation panel’s
surface should be kept dry and clean so as to avoid pollutions which may lower down the
insulation performance to bring short circuit.
4-2 Laser Power supply
This machine can be operated either through the keys on the control panel or the joystick.
(1) Principle
The laser power supply system with repetition rate is employed, the L—C resonance
charging is adopted for the charging circuit. The capacitance-inductance energy storage
network is used for supplying the power for the lamp. The control circuit is centered by the

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single-chip microprocessor, which can be used to adjust the output energy of power and the
repeated frequency. The system also features its multiple linked protections, ensuring the
emergency stop of the power under abnormal conditions.
(2) Electric circuit
The electric circuits are made up of the following parts:
Main return circuits: including the charging circuit, energy storage network, discharging
circuit and pre-burning and trigger circuit.
Controlling circuits: including the electric controlling circuit, microprocessor controlling circuit
and different kinds of protection circuits.
A.Step-up/rectification circuit: it employs the single-phase stepping up, which converts AC
220V into DV 500V that supplies power to the charging circuit.
B. Charging circuit
The charging circuit is composed of the IGBT switch tubes. Such a charging mode will
increase the repetition rate of the circuit.
C. Discharging circuit
The discharging circuit can be controlled by the silicon controlled switch that must be kept
shut off. After the energy storage network is charged, the silicon controlled switch is shut off,
then after the delayed time, the discharging can be realized by turning on the silicon
controlled switch. Once the energy storage capacitance is fully discharged, the silicon
controlled switch will be automatically shut off.
D. Pre-burning and trigger circuit
It is made up of the step-up and transforming circuit, high voltage bridge rectifier, filter,
current-limiting resistor; current relay, high voltage pulse transformer and high voltage trigger
circuit.
As the pulse xenon lamp is in the state of normal glow discharge when it is pre-burned, it has
the nature of negative resistance. To ensure the normal glow discharge of the xenon lamp
after the arc-discharge is finished, the pre-burning circuit must have the nature of high
current source and its current-limiting resistor must be relatively high. The internal triggering
mode is employed for this machine, with 50Hz automatic triggering. Once the pre-burning
switch is closed, the high voltage pulse transformer will generate high voltage of 15-20 kv to
be applied onto the resonance cavity. As long as the pre-burning is established, the trigger
circuit will be disconnected immediately.
E. Protection circuit
a) Pre-burning disconnection protection
When the pre-burning current is shut off, the discharging circuit will have failure, the
protection circuit will be activated to send out failure signal.
b) Flow interlocking protection
When the flow of the circulating water inside the cooling system is insufficient, the flow

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breaker will be opened and the pre-burning circuit and main circuit will be disconnected,
resulting in the shutoff of the whole machine.
4-3 Optical system
Figure 4-1
Two off-focus modes are available: positive off-focus and negative off-focus. If the focal
plane is above the work piece, it is called positive off-focus, contrarily; it is called negative
off-focus.According to the theory of geometrical optics, when the positive off-focus distance
is the same as the negative off-focus distance, the power density on corresponding planes
will approximate to each other. However, the shape the obtained molten pool is different.
Under the circumstance of negative off-focus, the large penetration depth could be reached,
which is related to the forming of the molten pool. Experiments show that when the material
is heated by laser for 50～200us, it begins to be molten, forms the liquid-phase metal and
the evaporation appears to form the pressure-applying vapor that spurs at extremely high
speed with dazzling white light. At the same time, the high density gas moves the
liquid-phase metal to the edge of the molten pool to form the dent at the center of the molten
pool. Under the circumstance of negative off-focus, the power density inside the material is
even higher than the surface, which is apt to cause stronger melting and vaporizing that
Impact of Focus Setover on Welding Quality
The laser welding normally needs a certain degree of off-focus operation, for the welding
point can be vaporized into a hole if the power density at facula center of laser focus is
excessively high. The planes that are not with the laser focus will have relatively even
distribution of power density.

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pass the optical energy into the in-depth part of the material. Therefore, in actual
applications, if the large penetration depth is required, the negative off-focus operation
should be carried out. When thin materials are welded, the positive off-focus operation is
needed.
(1) Microscope/ CCD
This machine employs the binocular zoom stereo microscope, featuring its clear and stereo
vision. The coated protection glass is added in front of the object lens to avoid the pollution
which can be caused by the splashing metal articles during processing. For transportation
and storage, the ocular can be removed by loosening the fixing screws.
(2) Laser extending and focusing system
The machine employs the design that both the laser and microscope’s beam path share the
same object lens. The focus setover is determined by the welding process and adjusted by
the off-focus handle, with procession graduation marks.
(3) Welding point indication
There is a reticle in the object lens, the intersection point of which is overlapped with the
laser point. Through the intersection point of the reticle, the laser beam can be aligned to the
welding part during work.
(4) Precautions
A. The surface of optical parts can’t be contacted or wiped with hand, cotton yarn or hard
object, nor blown with mouth. The blowing ball can be used to remove the dust on them. If
there is any pollutant, the operator can use cotton wool or lens paper moistened by cleaning
agent to clean them
B. To avoid damage, do not dismantle the parts. Otherwise, dust or smoke may enter into the
inside of the optical system.
C. When the protection glass needs to be replaced, the object lens and the press ring should
be removed. Replacement work should be done with great care.
4-4 Cooling system
(1)Structure
The cooling system is enclosed water circulation system composed of heat exchanger,
magnetic pump, filter, water tank, flow switch and temperature contactor, valve and other
parts.
(2) Working principle
The magnetic pump pumps the deionized water in the water tank that will cool the working
material (YAG bar), xenon lamp, lamp electrode of the laser. The deionized water with
absorbed heat will pass by the heat exchanger discharging the heat and flow back to the
water tank.

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The resistance rate of the deionized water is required to be higher than 0.5MΩ—cm. After
some time of use, the deionized water’s resistance rate will be lowered down and it may
have impurities, dirt or turbidity that will make the xenon lamp not lightened or pollute the
laser cavity and glass tube, and lower the luminous efficiency. If so, the used deionized
water should be substituted immediately (if the machine is continuously operated, the
deionized water in the system should be replaced once a week).
The heat exchanger works through the Freon to exchange the heat for the cooling water and
carry away the heat in the purified water. A flow controller and over-temperature contactor
are installed in the cooling system to monitor the water that comes into the laser. Once the
flow of the circulating water is insufficient or the water pump in the system works abnormally,
the power for the laser should be turned off immediately so as to avoid the accident that can
be caused by the explosion of the lamp bar.
parameters (for reference)
Material
Current（A）
Pulse（MS）
Frequency（HZ）
0.3MM SS
50
1-2
5-10
0.5MM SS
60
1-2
5-15
0.8MM SS
70
1-2
5-30
1.2MM SS
80
1-2
5-30
0.3MM Titanium
50
1-3
5-10
0.8MM Titanium
60
1-4
5-30
0.5MM Zinc
80
1-4
5-10
1.0MM Zinc
100
1-4
5-15
0.3MMAluminum
100
1-3
3-10
0.5MMAluminum
120
1-3
3-10
0.8MMAluminum
140
1-3
3-10
1.2MMAluminum
160
1-3
3-10
1.5MMAluminum
180
1-3
5-15
0.6MM Brass
100
2
5-10
1.0MM Brass
110
2
5-15
The parameters aboved are based on 200W channel letter laser welder. Should for 300W and 400W
machine, the current and pulse width should be decreased, the min. current is 50A. Should the laser is
strong, then reduce pulse width, or enlarge the facular.
Whatever the material is, the best welding is the proper facular when focus length is correct. There will be

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Address: A7-101, Hangyu building, Wuhan University Sci & Tech Park, East Lake High-tech Dev. Zone, Wuhan, Hubei, China
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clear welding sound when get the right facular. Should low voice welding, lower down the facular and vice
versa.
Attachment 2: Common Troubleshooting
Fault
Possible Reasons
Proper Solutions
Machine won’t work with the
power on
1. Flow alert is not connected
2. AC fault
1.Check the water chiller connection
2.Check the total power supply
Xenon lamp won’t light up
with the power on
1.Lamp is broken
2.Lamp tube gets black
3.Pre-ignition circuit failure
4.Lamp’s service life runs out
5.Lamp poles fall off
1.Replace a new lamp
2.Change the water in the chiller
3.Check the volts according to the circuit map
4.Replace a new lamp
5. Check and plug the poles
Cooling fan won’t work with
the power on
Fan power failure
Replace a new fan
Output energy reduce
1.Water polluted
2.lamp worn out
3.Condenser cavity worn out
1. Change the water in the chiller
2.Replace the lamp
3. Clean or replace the condenser cavity
If the above steps do not correct the malfunction, do not disassemble. Please do not hesitate to contact us and
please operate under the guidance of our engineers.