If your fume extractor fails to start, does not respond to controls, or operates abnormally, the first step is to identify the cause. Power supply, wiring, control panel, and fan faults can produce similar symptoms. A machine that does not run does not necessarily have a faulty mainboard.
Once KNOKOO technical support has confirmed that mainboard replacement is necessary, use the accompanying video to understand the removal and installation process.
In this guide, “mainboard” refers to the internal circuit board shown in the video. Confirm the correct part number and compatible revision with KNOKOO before ordering or installing a replacement.
Important: The video does not identify the exact machine model, connector functions, or functional testing procedure. This guide does not replace the model-specific service instructions or wiring diagram.
For a visual walkthrough, watch the mainboard replacement video at the end of this article.
Prepare the following tools and materials:
The video shows a powered screwdriver. If using one, control the torque carefully to prevent board distortion, damaged mounting holes, or stripped threads.
Before starting, verify the machine model, serial number, rated voltage, original board number, and connector layout. Boards with similar appearances may not be interchangeable, particularly across different voltage ratings, fan configurations, or control revisions.
Mainboard replacement must be carried out by qualified service personnel.
Switch off the machine, disconnect all power sources, and prevent accidental reconnection. Wait until the fan has stopped completely.
Follow the model-specific service procedure for stored electrical energy. A qualified person must verify that the equipment is safe before touching internal components. Capacitors may retain charge after disconnection; a blank display or elapsed waiting time alone does not confirm that the equipment is safe.
Do not attempt to discharge capacitors by shorting their terminals. Where contaminated filters or internal dust are present, use protective measures appropriate to the substances collected.
The video begins with the enclosure already open. Power isolation and cover removal are not shown, but these steps must not be omitted during an actual repair.
Video reference: approximately 00:00–00:14.
Before disconnecting anything, take an overall photograph of the internal layout. Then take close-up photographs showing:
At the beginning of the video, the technician disconnects the plugs attached to the mainboard.
Hold each plug by its body. If it has a locking clip, release the clip before gently withdrawing the plug in its insertion direction. Do not pull directly on the wires.
Do not identify connections by wire color alone or rely on memory during reassembly. Label similar plugs and follow the wiring diagram for the specific machine.
Video reference: approximately 00:14–00:52.
After disconnecting the relevant wiring, remove the board’s mounting screws and associated fasteners.
Where a spanner is required, use the appropriate end of the 10 × 12 mm spanner to hold or loosen the fastener, preventing the mounting support from turning with the screw.
During removal:
The number and location of fasteners may vary by model. Follow the actual mounting arrangement.
Video reference: approximately 00:52–00:58.
Once the fasteners have been removed, the technician lifts the old mainboard out of its mounting position.
Handle the board by its edges wherever possible. Avoid pressing on components or pulling on the heatsink.
If the board does not lift out easily, check for remaining connectors, fasteners, or other attachments. Do not force or pry it free.
Place the removed board on a suitable antistatic surface and retain it until after-sales support has completed any required fault assessment.
Video reference: approximately 00:58–01:27.
Place the confirmed compatible replacement board in the original mounting position. Align its mounting holes with the supports, ensuring that no wires or foreign objects are trapped underneath.
Start each fastener loosely. Once the board is correctly positioned, tighten the fasteners progressively.
Restore the original spacers, washers, and insulating parts according to the model-specific assembly requirements. Do not add or remove these parts without technical confirmation.
Check that the board is securely mounted, remains flat, and does not interfere with nearby components.
The video does not show fan removal. Avoid disturbing components unrelated to the mainboard replacement.
Video reference: approximately 01:27–01:52.
With the board secured, reconnect each plug using the photographs, cable labels, and model-specific wiring diagram.
For every connection, confirm that:
The video does not clearly show every terminal marking. It must not be used to infer specific power, fan, or control-signal connections.
If the replacement board has a different connector layout, stop installation and contact KNOKOO technical support before proceeding.
The following checks supplement the video and form part of the repair verification process.
Confirm that the board is securely mounted and all wiring is correct. Check that protective earthing and the original insulation arrangements remain intact.
Account for all tools and fasteners. Refit the enclosure cover, guards, and any other parts removed during maintenance.
Electrical safety checks must be completed by qualified personnel according to the requirements for the specific machine.
Once the equipment has been confirmed safe to energize, check:
If smoke, sparks, a burning smell, or repeated circuit-breaker trips occur, stop using the machine immediately, disconnect power, and contact after-sales support. Do not repeatedly attempt to restart it.
With the normal filters and ducting restored, check extraction at the collection point.
If the controls operate normally but suction remains weak, inspect for blocked filters, kinked ducts, leaking connections, or unsuitable hood positioning.
Replacing the mainboard does not replace routine filter maintenance and will not resolve every airflow problem.
Providing complete information helps the service team assess the fault and identify the correct replacement parts.
Contact your original KNOKOO sales representative or use the contact channels on the KNOKOO website. Include the following:
| Information | Details to Provide |
|---|---|
| Equipment identification | Model, serial number, nameplate photograph, and rated voltage |
| Order information | Order number or proof of purchase |
| Fault description | Failure to start, fan not running, speed-control failure, or other specific symptoms |
| Fault video | Operating sequence, display status, and abnormal sounds |
| Mainboard information | Board number, connector photographs, and wiring photographs taken safely by service personnel |
The support process should begin with fault assessment, followed by confirmation of the correct replacement-board revision.
Replacement-part compatibility, availability, pricing, and delivery arrangements are subject to confirmation for the specific service request.
After completing the repair, provide a video showing startup, speed adjustment, and operation. Retain the repair date, replacement-board number, and test results for future service reference.
KNOKOO provides a one-year equipment warranty, excluding filter consumables.
The warranty commencement date, fault coverage, replacement-part arrangements, and shipping costs are governed by the applicable order and warranty terms. Warranty eligibility is assessed using the equipment information and confirmed cause of failure.
Continue inspecting filters, ducting, air inlets, and outlets according to the machine’s operating instructions. Prevent liquids and conductive dust from entering the electrical compartment.
Record any unusual alarms, odors, or changes in operating behavior and contact technical support when needed.
Need help confirming a mainboard fault or selecting a replacement? Send KNOKOO your machine model, serial number, and fault video so the technical team can confirm the repair approach before replacement begins.