FAQ

Generally, prophylaxis contra-angle handpieces feature a seal on the head that prevents the ingress of saliva and paste. This extends the lifespan of the contra-angle handpiece.

The most effective removal of discolouration that at the same time protects the enamel and dentine as much as possible, depends on the polishing speed, i.e. revolutions per minute, among other things. With a speed ratio of 4:1 (four revolutions of the motor mean one revolution of the cup), the revolution speed of the Prophy cup is reduced. This means during application, there is no risk of paste splattering.

All adaptors that are suitable for the Assistina 3x2/3x3 can also be used in the Assistina TWIN. There is only one exception: the RM/ISO adaptor for the Assistina 3x2/3x3 is not compatible with the Assistina TWIN. The HPI adaptor can be used for the Assistina TWIN instead.

During the maintenance process in the Assistina TWIN, the rotating parts are lubricated with oil and the spray channels rinsed with cleaning solution. These liquids are introduced to the handpieces using compressed air, which produces aerosols that may contain potentially contaminated body fluids (e.g. blood and saliva). In order to ensure that the apparatus poses no risk to the user, the patient or third parties, the law stipulates that aerosols must be prevented from leaking out of the apparatus. We make sure of this by using active suction and the HEPA filter. This HEPA filter must of course be changed regularly, which is why the lifespan of the filter is matched exactly to the capacity of the two cartridges. The HEPA filter therefore reaches the end of its service life once one set of cartridges has been used.

HEPA is short for 'High Efficiency Particular Air', and the filter is classified as HEPA class E11. This means that the filter retains all particles larger than 1 µm, which includes, among other things, a wide range of bacteria and viruses, suspended particles such as dust and respirable aerosols.

The intelligent process monitoring system documents the number of maintenance cycles that have been performed, thereby automatically calculating the number of instruments that can be serviced with the remaining quantity of fluid. The user receives an alert 300 cycles before the cartridge needs replacing (the oil and cleaner LEDs on the top of the unit turn yellow in colour).

The consumption volumes for each instrument are 0.07 ml of oil and 0.07 ml of cleaning solution. This gives a maximum capacity of 2857 cycles. In reality, the value is around 2800 to 2850 cycles, as initial filling is also required and the fill quantity of the cartridges is subject to certain tolerances that are regulated by the applicable standards.

The two cartridges and the filter can be changed easily without any tools. As with the Assistina 3x2/3x3, the fluid is supplied via tapping needles in the bottom of the cartridge spaces that penetrate the cartridge membrane, thereby drawing the fluid out of the cartridge. The two cartridges have different shapes to ensure that the two fluid types cannot be mixed up. In addition, it is only possible to install the HEPA filter incorrectly by using force, which is not necessary.

The oil is atomized in the Assistina TWIN before it is enters the instrument. This ensures full coverage of the gear parts, eliminating the need for technically complex and time-consuming rotational lubrication. However, there is no negative impact on the maintenance quality: the results of a maintenance operation correspond to those achieved with the Assistina 301 Plus.

If you are not sure what the cause of the problem is, it is better to call the service station and talk to a technician. Together with the technician it can be determined what needs to be sent in and sometimes it is possible to even solve the problem right away.

If you are not completely sure of the cause of the problem, it is better to contact your W&H service partner first and speak to a technician. It is sometimes possible to resolve malfunctions together with the technician and decide what needs to be sent in for repair.

The brushless electric motor is considerably less susceptible to wear than a brush motor, which in turn translates to minimised service and maintenance work. This also means less downtime for the user when servicing proves necessary.

The W&H Synea series – the glass rod elements are optimally suited for use together with the EM-12 L motor and its integrated LED+.

The EM-12 L electric motor can be integrated into a dental unit by selected dental unit manufacturers or their service technicians.

To connect the EM-12 L electric motor to your dental unit as an Add-on you require a free turbine hose on your dental unit and the possibility of connecting the control to the mains via the included power supply unit. You can control the EM-12 L electric motor using the foot control of your dental unit.

Yes, if your EM-12 L electric motor features the symbol “Sterilizable up to the stated temperature”.

No, that is not possible.

The Built-in electronic component does not require separate maintenance. However, regular servicing together with the rest of the dental unit should be performed at the intervals prescribed by the pertinent legislation. This makes it possible to guarantee proper function and safety. More detailed information on this topic can be found in the “Service” section of the respective instructions for use.

The EM-12 L electric motor as an Add-on version including accessories requires a regular check once every three years unless shorter intervals are prescribed by law. The regular service must only be performed by an authorised W&H service partner. More detailed information on this topic can be found in the “Service” section of the instructions for use.

POSSIBLE CAUSE
Printer not properly connected or not powered
SOLUTION
Check the data and the power connection to the printer.

POSSIBLE CAUSE
Water fill system not connected
SOLUTION
Connect the water fill system to the sterilizer (see ANNEX 7 for water quality requirements).

POSSIBLE CAUSE
When the water fill system attempted to fill the tank, water was temporarily unavailable
SOLUTION
Since water tank filling is attempted only once in-between cycle execution, this event inhibits water feeding. Switch the sterilizer OFF and then ON again.
Check the external water supply system.
Check for water leaks from the sterilizer.

POSSIBLE CAUSE
Faulty MIN water level sensor in the clean water tank
SOLUTION
Call service.

POSSIBLE CAUSE
The main switch or network circuit breaker is OFF
SOLUTION
Activate the main switch or network circuit breaker (ON).

POSSIBLE CAUSE
No voltage at the socket
SOLUTION
Check the electric circuit.

POSSIBLE CAUSE
The power cord is not connected properly
SOLUTION
Check and connect the power cord properly

POSSIBLE CAUSE
Leaks through the chamber door seal
SOLUTION
Clean or replace the door seal. Clean the door surface facing the chamber.

POSSIBLE CAUSE
Internal leak.
SOLUTIONS
Contact a service engineer.

POSSIBLE CAUSE
The thermal overload switch is open
SOLUTION
Reset the thermal overload switch (see RESETTING THE THERMAL OVERLOAD).

POSSIBLE CAUSE
Electric – electronic fault

SOLUTION
Contact a service engineer.

POSSIBLE CAUSE
Sterilizer not properly levelled
SOLUTION
Properly level the surface that the sterilizer is placed on.

POSSIBLE CAUSE
Overloaded chamber
SOLUTION
Comply with the maximum load weight limits for each type of load. Always use the chamber rack for trays and cassettes.

POSSIBLE CAUSE
Chamber filter clogged
SOLUTION
Remove and clean the chamber filter.

POSSIBLE CAUSE
Chamber filter cap mispositioned
SOLUTION
Mount the chamber filter cap properly (see chapter MAINTENANCE)

POSSIBLE CAUSE
Load incorrectly placed
SOLUTION
Follow the recommendations as listed in ANNEX 2.

POSSIBLE CAUSE
Tap water on instruments when placed in the sterilizer
SOLUTION
Ensure that instruments are dry before they are placed in the sterilizer.

POSSIBLE CAUSE
Use of water of poor quality or water containing chemical substances
SOLUTION
Drain both water tanks. Use good quality water (see APPENDIX 7).

POSSIBLE CAUSE
Organic or chemical residues on the instruments
SOLUTION
Clean, rinse and dry instruments before placing them in the sterilizer (see APPENDIX 2).

POSSIBLE CAUSE
Chamber, trays, tray rack dirty
SOLUTION
Clean the chamber and wash the chamber furniture

POSSIBLE CAUSE
Contact between instruments of different materials
SOLUTION
Ensure that instruments of different materials do not touch (aluminum, carbon or stainless steel, etc.); place them on different trays or cassettes or pouch them (refer to APPENDIX 2).

POSSIBLE CAUSE
Scale deposits on the chamber
SOLUTION
Clean the chamber and use good quality water (refer to APPENDIX 7).

POSSIBLE CAUSE
Incorrect temperature selected
SOLUTION
Select a sterilization cycle featuring a lower sterilization temperature. Follow the instructions of the instrument manufacturer.

POSSIBLE CAUSE
An electronic board was replaced when serviced.
SOLUTION
None. The memory of the old board cannot be restored. You are advised to Save the history regularly onto the USB pen drive.

POSSIBLE CAUSE
Door seal not properly placed; seal sticking out
SOLUTION
Ensure that the door seal is correctly inserted around the whole circumference.

POSSIBLE CAUSE
Door jammed by external objects or by the load itself
SOLUTION
Remove any objects interfering with the chamber door. Check that the door does not push against the load or the chamber furniture.

POSSIBLE CAUSE
The chamber door has not been opened after the previous cycle had finished and the “Sleep mode delay” has expired
SOLUTION
Press the SLEEP MODE button to exit.

POSSIBLE CAUSE
The chamber is in vacuum due to an internal malfunction
SOLUTION
Switch the sterilizer OFF: this releases any internal pressure allowing the chamber door to be opened. Call technical service if the problem persists.

POSSIBLE CAUSE
The bacteriological filter is blocked
SOLUTION
Remove the bacteriological filter to release the pressure. Replace the filter. Note that bacteriological filters need to be replaced every 400 cycles.

POSSIBLE CAUSE
The chamber temperature dropped below the minimum threshold and the software performed a successful recovery
SOLUTION
Wait for cycle completion. If the problem occurs frequently, contact a service engineer.

POSSIBLE CAUSE
The USB mass storage is not connected or not properly connected to the sterilizer.
SOLUTION
Check presence and connection of the USB pen drive. If the problem persist, contact a service engineer.

POSSIBLE CAUSE
A component needs replacing for the programmed maintenance of the sterilizer.
SOLUTION
Order the requested component (door seal, dust filter, bacteriological filter…). See “Maintenance” chapter.

Yes, testing is an integral part of ensuring that a small sterilizer consistently performs to operating parameters set during the machines commissioning. Failure to carry out routine periodic tests and maintenance tasks could compromise safety and have legal and insurance-related implications for the registered Manager.

Validation is a documented procedure for collecting, recording and interpreting data required for proving that a procedure constantly complies with the specified specifications. W&H sterilizers feature a process evaluation system, which continually monitors the stipulated specifications (temperature, pressure and time).

Country/regional specific laws and guidelines referring to periodical testing or routine monitoring are individual and must be considered. Our recommendation for periodical testing is mentioned in the delivered IFU and depends on the integrated features in your sterilizer.

W&H recommends to record all periodic tests, repairs and modifications on the sterilizer in the logbook including date and signature of the person who carried out the test or other activity.

Keep the results according your country/regional specific laws and guidelines and the definitions in your QM. Those records can be of assistance in case of service as well.

Validation generally comprises a range of tests defined in internationally recognised standards. These tests begin for every device with the factory tests at W&H. In addition, corresponding documentation is included with your device. Prior to commissioning the device at your premises, the technician performs further checks to ensure the device functions correctly. Then, depending on the national/regional laws and directives, the device must be subjected to a so-called renewed performance qualification at regular intervals. For further information, please contact your dealer.

All validation and maintenance work should be performed by a qualified individual.

Information and videos relating to consumable components and how to replace them can be found on the Consumables & Accessories and Video Tutorial section of this web site.

Information and videos relating to the cleaning of the water tanks and cleaning products can be found on the Video Tutorial section of this web site.

The water quality for sterilizers is internationally specified by standards and directives. The reasons for this are that your sterilizer can be seriously damaged by it or the sterilization can be jeopardised. Consequently, only water with conductivity of less than 15 µS/cm should be used for your W&H sterilizer. The Multidem system (LINK) is especially suited to preparing suitable water.

To ensure that your instruments are stored in a sterile state from their successful sterilization until they are used, W&H recommends packing them in suitable sterile barrier systems from even before sterilization. The recommended storage periods can be found in your national/regional laws and directives. For further information, please contact your dealer.

If you are not sure what the cause of the problem is, it is better to call the service station and talk to a technician. Together with the technician it can be determined what needs to be sent in and sometimes it is possible to even solve the problem right away.

> To measure the ISQ of an implant, you first screw a so called SmartPeg into the placed implant. The SmartPeg, with its magnet on top, works like a small tuning fork. The magnet on the SmartPeg is ‘hit’ with magnetic pulses, from the probe, which makes the SmartPeg vibrate. Due to the stiffness in the interface between the implant surface and the bone the SmartPeg will vibrate accordingly. The more dense the bone is the higher stability and the higher ISQ value.

Please contact your local W&H partner
The sale of SmartPegs will be defined per country
The surgeon will receive 5 free SmartPegs. A voucher will be provided with the delivery of the product.

The Osstell ISQ technology is proven by over 700 scientific studies. These studies have shown, that torque and ISQ correlate.

Torque is a one time, static measurement at the time of placement of the implant and cannot be repeated later on in a non-invasive way. Osstell ISQ measures the lateral stability of the implant and the measurements can be repeated in a non-invasive, dynamic way to monitor the development of osseointegration.

Yes. All control units SI-1023, SI-1015 and SI-1010 can be upgraded with the W&H Osstell ISQ module

The surgeon or dental nurse can easily attach the module to the right side of the Implantmed with the help of the provided quick manual. The module is plug-n-play via a USB connection.

> To measure the ISQ of an implant, you first screw a so called SmartPeg into the placed implant. The SmartPeg, with its magnet on top, works like a small tuning fork. The magnet on the SmartPeg is ‘hit’ with magnetic pulses, from the probe, which makes the SmartPeg vibrate. Due to the stiffness in the interface between the implant surface and the bone the SmartPeg will vibrate accordingly. The more dense the bone is the higher stability and the higher ISQ value.

Please contact your local W&H partner
The sale of SmartPegs will be defined per country
The surgeon will receive 5 free SmartPegs. A voucher will be provided with the delivery of the product.

Torque is a one time, static measurement at the time of placement of the implant and cannot be repeated later on in a non-invasive way. Osstell ISQ measures the lateral stability of the implant and the measurements can be repeated in a non-invasive, dynamic way to monitor the development of osseointegration.

Yes. All control units SI-1023, SI-1015 and SI-1010 can be upgraded with the W&H Osstell ISQ module

The surgeon or dental nurse can easily attach the module to the right side of the Implantmed with the help of the provided quick manual. The module is plug-n-play via a USB connection.

No. The new motor has a new technological basis and is the shortest available

The LC stands for Light Contacts. This means that we have integrated an electrical connection into our new motors. The Light Contacts deliver power to our new contra-angles to offer our customers the best light at any rotation speed. For oral surgery handpieces from W&H, the LED remains in the head of the contra-angles

Yes. All W&H surgical contra-angles and handpieces can be attached to the new motor EM-19.

No. In order to deliver the best balance we shortened the inner coupling length. Therefore contra-angles with only an L suffix cannot be attached to old motors

Yes. At W&H the letter "S" always communicates, that the surgical contra-angle is disassemble. The letter "I" communicates, that the surgical contra-angle cannot be disassembled (e.g. WS-75 L vs. WI-75)

No. The new cable foot control S-N2 is based on the industrial CAN standard. So connecting the old foot control S-N1 is not possible.

W&H introduces a new concept in oral surgery and implantology. Via dongles (receiver), which can be connected to the unit by the doctor, the wireless foot control S-NW communicates with the surgical units of W&H.

It depends but basically yes. The following units can be retrofitted
Implantmed SI-923 REF16929000
Implantmed SI-915 REF16929001
Elcomed SA-310 REF15933100/15933101/15933102/15933103
Please contact your local W&H Partner to find out if the wireless foot control is already registered in your country

The generator in the contra-angle handpiece requires at least 300 rpm to produce enough electricity for the LED. The rotary speed is between 15 and 50 rpm when positioning an implant.

No, the speed in program P4 is 15 rpm when in forward operation and 30 rpm in reverse operation. In program P5 (thread cutter function) the speed is 20 rpm in both forward and reverse operation and only the torque can be set.

No, the Implantmed/Elcomed motor does not need greasing. The motor bearings require no maintenance. Any additional greasing would reduce the service life of the bearings.

The torque can be adjusted in P4 & P5 only. In- or decreaseing is done via either "+" or "-" button. A detailed description (factory settings, adjstable range,…) can be found in the user manual.

For applications which do not require accurate torque (drilling, grinding,…), any handpiece with ISO 3964 connection can be used. Please be informed that hand pieces from other manufacturers might not be able to handle the torque of your unit/motor and therefore might get damaged.

Not recommended. Due to different specifications (material, dimensions) it could cause problems like leakage, insufficient cooling or even damage the unit. For propper tubing see "correlation of tubing" or user manual.

Please find a detailed description in the user manual at chapter "Starting operation - General".

Please find a detailed description in the user manual at chapter "Hygiene and Maintenance".

Yes, if the thermal washer disinfector has a drying cycle and the motor bears the sign that it is "Thermo washer disinfectable".

No. The new generation of motors have to be sterilized without cap.

Regular servicing of function and safety including the accessories is necessary and should be carried out at least once every three years, unless shorter intervals are prescribed by law. Detailed information can be found in the user manual at chapter "Servicing".

If you are not sure what the cause of the problem is, it is better to call the service station and talk to a technician. Together with the technician it can be determined what needs to be sent in and sometimes it is possible to even solve the problem right away.

For propper tubing see "correlation of tubing" or user manual.

No. In order to deliver the best balance we shortened the inner coupling length. Therefore contra-angles with only an L suffix cannot be attached to old motors

Yes. At W&H the letter "S" always communicates, that the surgical contra-angle is disassemble. The letter "I" communicates, that the surgical contra-angle cannot be disassembled (e.g. WS-75 L vs. WI-75)

The generator in the contra-angle handpiece requires at least 300 rpm to produce enough electricity for the LED. The rotary speed is between 15 and 50 rpm when positioning an implant.

Yes, providing that your W&H handpiece carries the relevant sterilization symbol.

Internal and external parts are of high quality stainless steel (including the contra-angle handpiece head).

Yes, W&H handpieces with LED and generator are both sterilizable and thermodisinfectable .

See detailed description in user manual or Video.

Yes. In order to extend the live span of the clip, W&H recommends to remove the clip from the hand piece and sterilize it separately (hand piece and clip in one pouch but separated).

Both assure maximum performance. The WS-75 can be dismantled and therefor it can be cleaned more thoroughly.

If you are not sure what the cause of the problem is, it is better to call the service station and talk to a technician. Together with the technician it can be determined what needs to be sent in and sometimes it is possible to even solve the problem right away.

Alegra LED turbine handpieces are exclusively intended for use with Roto Quick couplings RQ-54 / RQ-53. Alegra LED turbine handpieces cannot be coupled onto Roto Quick couplings RQ-24 / RQ-34.

Use your thumb and index finger to retract the coupling's retention sleeve. The turbine can now be removed from the coupling without any problems. Pulling forcefully on the dental turbine can cause damage. If excessive force is required to remove the turbine, verify that the retention sleeve on the coupling can be moved without any problems.

Turbines with standard head sizes (models XX-98): 19 mm - 25 mm Turbines with small head sizes (models XX-97): 16 mm - 21 mm

The cutting part diameter for both head sizes is restricted to max. 2 mm. Please observe the technical data provided by the bur manufacturer. When using longer, rotary instruments for special treatment indications, the user must always select the operating conditions correctly in order to avoid placing the user, patient or anybody else at risk.

Please check drive air pressure on your unit and maintenance of the instruments (Synea with RQ connection = 3 +/- 0,3 bar, with Multiflex® connection 2,5 - 4 bar). For all Alegra turbines the pressure needs to be set between 2,5 - 2,8 bar.

Yes, providing that your W&H turbine carries the relevant sterilization symbol.

Yes, providing that your W&H turbine carries the relevant thermal disinfection symbol and the thermo disinfector should have a drying cycle.

25 mm for the standard turbine (XX-98 modells) and 21 mm for turbines with small head (XX-97 modells). When using longer rotary instruments the user must ensure by correct selection of the operating conditions, that there is no danger to the user, patient or third parties.

Yes, it is neccesary to properly adjust the air/water pressure and if applicable the voltage for the turbine.

If there is electricity at the end of turbine hose, you need a proper coupling and a turbine with light (example: RQ-24 and TK-97 L). If no electricity is available, the simplest way is to buy a W&H Alegra turbine with LED and its Roto Quick coupling (e.g.: TE-97 LQ and RQ-54). It doesn't require any other investment in the dental unit.

If you are not sure what the cause of the problem is, it is better to call the service station and talk to a technician. Together with the technician it can be determined what needs to be sent in and sometimes it is possible to even solve the problem right away.

The handpieces in the new Alegra range have been tested and approved for the following applications removing cariogenic materials, preparing cavities and crowns, removing fillings and finishing tooth and restoration surfaces. The use of the handpieces in other application areas is not permitted and the user bears all responsibility in cases where this instruction is disregarded.

No, because they are usually operated with coolant air. In addition, the LED contra-angle handpieces are equipped with an internal spray function, which guarantees additional cooling.

Compatible LED light – the instruments in the new Alegra range have LED light, which is supplied with energy by an integrated generator. The instruments are therefore independent of the light supply of the motor and the dental unit and offer the possibility of working with light compatible with any unit. The technology of the integrated generator means that there is only illumination when the instrument is running.

Because the energy for the LED light in the new Alegra instruments is generated by an integrated generator, the brightness of the LED depends on the motor speed (at least 9.000rpm).

Yes, providing that your W&H handpiece carries the relevant sterilization symbol.

The optimum speed of fast-running burs can easily be achieved using the WE-99.

Yes, W&H handpieces with LED and generator are both sterilizable and thermodisinfectable .

Yes, the straight and contra-angle handpieces of the new Alegra range can be used on any motor with an ISO connection. .

Yes, providing that your W&H instrument carries the relevant thermal disinfection and sterilization symbol and the thermo disinfector should have a drying cycle.

If you are not sure what the cause of the problem is, it is better to call the service station and talk to a technician. Together with the technician it can be determined what needs to be sent in and sometimes it is possible to even solve the problem right away.

You can use any file systems on the market which are suitable for rotating preparation, have a 2.35 mm standard sheath and a torque of at least 0.5 Ncm.

Once the set torque is reached, the set mode (auto forward or auto reverse) is activated and Entran makes five attempts to remove the file. If it is not successful, Entran stops. It is recommended to restart it. If the file still cannot be removed, it should be released from the chuck system and removed manually.

It is not recommended to use Entran with a Gates Glidden bur as the low speed is insufficient to guarantee high removal efficiency.

In addition to the overview of the values on the file cards included in the Entran's scope of delivery, the file manufacturers also provide information on the files' maximum torques.

One fully charged battery is enough for over 20 treatments.

When the battery indicator starts flashing, there is enough time to finish the treatment. Afterwards, the ENTRAN needs to be charged.

If the battery is completely dead, it will take approximately 90 minutes to charge fully.

If you are not sure what the cause of the problem is, it is better to call the service station and talk to a technician. Together with the technician it can be determined what needs to be sent in and sometimes it is possible to even solve the problem right away.

Use your thumb and index finger to retract the coupling's retention sleeve. The turbine can now be removed from the coupling without any problems. Pulling forcefully on the dental turbine can cause damage. If excessive force is required to remove the turbine, verify that the retention sleeve on the coupling can be moved without any problems.

A 6-hole connection for the turbine tubing is necessary to supply the turbine with electricity via electrical contacts. Other connections do not provide a power supply.

Yes. W&H also offers the "RM-34 LED" for Multiflex® connection.

No, thermodisinfection of the coupling is not permitted; sterilization in steam sterilizers can be applied at a temperature of 135°C. Hot air sterilization and/or cold sterilization (placing in liquids) are not approved.

If you are not sure what the cause of the problem is, it is better to call the service station and talk to a technician. Together with the technician it can be determined what needs to be sent in and sometimes it is possible to even solve the problem right away.

Yes, providing that your W&H handpiece carries the relevant sterilization symbol.

Yes, providing that your W&H instrument carries the relevant thermal disinfection and sterilization symbol and the thermo disinfector should have a drying cycle.

If you are not sure what the cause of the problem is, it is better to call the service station and talk to a technician. Together with the technician it can be determined what needs to be sent in and sometimes it is possible to even solve the problem right away.

A mixture of propane and butane (standard aerosol in all spray cans). It contains no CFCs and as such is environmentally-friendly.

In accordance with the national regulations for aerosol cans. More information on disposal can be found on the safety datasheet.

W&H Service Oil F1 has long­term stability between –30 oC and +160 oC.

Extensive research and testing produced a formula which best covers the extreme demands of dental instruments. It consists of an all-synthetic special oil of the highest purity supplemented by the specially developed additive package.

W&H recommends that W&H instruments are lubricated with W&H oil which has been designed and developed to enhance the performance of your W&H instrument.

Yes, providing that your W&H instrument carries the relevant thermal disinfection and sterilization symbol and the thermo disinfector should have a drying cycle.

If you are not sure what the cause of the problem is, it is better to call the service station and talk to a technician. Together with the technician it can be determined what needs to be sent in and sometimes it is possible to even solve the problem right away.

If you are not sure what the cause of the problem is, it is better to call the service station and talk to a technician. Together with the technician it can be determined what needs to be sent in and sometimes it is possible to even solve the problem right away.