# Error Codes This reference documents every error and warning code shown by KEMPER Connect for the supported device types. Each entry explains what the code means, the typical cause, the expected impact on extraction performance and the recommended action. ### Overview KEMPER devices report two kinds of conditions, each encoded as a bitmask on a dedicated status register: * **Errors (FAULT register)** — critical faults that stop or seriously degrade operation. Shown in red in the UI. Require immediate attention. * **Warnings (WARNING register)** — non-critical conditions that still allow operation, but indicate that something should be addressed soon. Shown in amber in the UI. A value of `0` on either register means the register is healthy. Any non-zero value is a sum of one or more active bits — the UI decodes the bitmask and displays each active condition with its code, short message and longer description. #### Where codes appear * **Asset list** — affected devices carry a red or amber badge. * **Dashboard** — a colored alert box lists every active code with a detailed description. * **Settings panel** — the current fault / warning register is shown, along with each decoded condition. #### How to read this document Each code is documented in the same format: * **Severity:** `Error` (critical, red) or `Warning` (non-critical, amber) * **Description:** What the condition means and why it matters. * **Typical causes:** Most common real-world reasons for this code. * **What to do:** Immediate actions to resolve or mitigate the issue. Codes that appear on multiple device types are described in full at their first occurrence; later sections cross-reference them. ### Bridge-connected devices Applies to **Automation Line**, **MaxiFil Clean** and **VacuFil Compact** — all devices that connect to KEMPER Connect through the KEMPER Connect Bridge. They share a unified fault and warning register layout. #### Fault codes (FAULT register) **`E01` — Frequency inverter error** * **Severity:** Error * **Description:** The frequency inverter (VFD) driving the fan motor reported a fault. The fan has stopped and extraction is no longer guaranteed. * **Typical causes:** * Motor overload or stalled impeller * Overvoltage, undervoltage or phase loss on the mains supply * Internal inverter fault * **What to do:** * Reset the device once it is safe to do so. * Check that mains supply is within the specified range. * Inspect the fan wheel for mechanical blockage. * If the fault returns immediately, read out the inverter's own diagnostic code and contact service. **`E02` — Modbus communication error** * **Severity:** Error * **Description:** The KEMPER Connect Bridge has lost the Modbus connection to the device controller. Sensor values in the UI may be stale and remote commands may not reach the device. * **Typical causes:** * Damaged, loose or unterminated Modbus cable * Incorrect slave address or baud rate * Electromagnetic interference on the bus * **What to do:** * Verify cabling, connectors and bus termination (120 Ω at both ends). * Confirm the Modbus address matches the Bridge configuration. * Power-cycle the Bridge and the device. **`E03` — Main contactor error** * **Severity:** Error * **Description:** The main contactor (power relay for the motor) did not switch as commanded. Motor power cannot be applied safely and there is a risk of unintended startup. * **Typical causes:** * Stuck or welded contactor contacts * Failed coil or auxiliary feedback contact * Wiring fault between controller and contactor * **What to do:** * **Do not operate** the device until cleared. * Contact KEMPER service — this fault must be resolved by qualified personnel. **`E04` — Motor protection relay error** * **Severity:** Error * **Description:** The motor protection relay tripped because of overcurrent or a short circuit in the motor circuit. * **Typical causes:** * Mechanical blockage of the fan (foreign object, damaged impeller) * Damaged motor winding or cable insulation * Protection relay set too sensitively * **What to do:** * Remove power and inspect the motor for mechanical blockages. * Measure winding resistance and insulation if the fault persists. * Reset the protection relay before restarting; if it trips again, contact service. **`E05` — Voltage supply error** * **Severity:** Error * **Description:** Supply voltage is outside the permitted range. The device shut down to protect its electronics. * **Typical causes:** * Missing phase or unbalanced mains supply * Undervoltage due to overloaded site circuit * Upstream UPS or transformer fault * **What to do:** * Verify mains supply (L1 / L2 / L3, N, PE). * Check the main fuses and any upstream protection. * Measure voltage under load; involve a qualified electrician if values are out of spec. **`E06` — Control unit error** * **Severity:** Error * **Description:** The internal control PCB detected an unrecoverable fault (watchdog, memory or firmware). * **Typical causes:** * Transient electrical disturbance * Corrupted firmware after a failed update * Hardware fault on the control board * **What to do:** * Power-cycle the device — this often clears transient issues. * If the error returns, contact KEMPER service for firmware reload or PCB replacement. **`E07` — Motor temperature too high** * **Severity:** Error * **Description:** The motor thermistor (PTC/KTY) has tripped. Continued operation can permanently damage the winding insulation. * **Typical causes:** * Excessive duty cycle at high extraction volumes * Blocked motor cooling openings * Restricted airflow (clogged filter, closed damper) * High ambient temperature in the installation area * **What to do:** * Let the motor cool down fully before restarting. * Inspect the cooling openings and the filter for blockages. * Reduce the duty cycle if the device is being operated continuously at maximum load. **`E08` — Filter pressure critical** * **Severity:** Error * **Description:** Differential pressure across the filter has exceeded the critical threshold. Airflow is severely restricted and the filter may rupture, allowing unfiltered air into the exhaust. * **Typical causes:** * Heavy filter loading that cleaning can no longer recover * End-of-life filter cartridges * Compressed air supply missing, so self-cleaning did not run * **What to do:** * Stop extraction immediately. * Replace or service the filter cartridges. * Verify that compressed air is connected and self-cleaning is enabled. **`E09` — Dust collection bin open** * **Severity:** Error * **Description:** The dust collection bin / drum is not closed or not seated correctly. Dust-laden air could escape into the workplace. * **Typical causes:** * Bin not re-seated after emptying * Damaged or misaligned door switch * Overfilled bin preventing correct closure * **What to do:** * Empty the bin if full and re-seat it with the safety clamps engaged. * Confirm that the door / bin switch activates when the bin is closed. **`E10` — Compressed air not connected** * **Severity:** Error * **Description:** No compressed air is detected. The automatic filter self-cleaning (jet pulse) cannot run, so the filter will clog rapidly and continuous safe operation cannot be guaranteed. * **Typical causes:** * Compressed air hose disconnected or leaking * Supply pressure below the minimum threshold * Closed shut-off valve upstream of the device * **What to do:** * Connect compressed air at approx. 5–6 bar. * Check for leaks and verify supply pressure at the inlet. * Open any upstream shut-off valves. #### Warning codes (WARNING register) **`A01` — Service overdue** * **Severity:** Warning * **Description:** The scheduled maintenance interval has been reached. The device still operates, but service should be carried out soon to keep it within specification. * **What to do:** * Book a service visit (filter check, seals, inspection, calibration). * Acknowledge the warning in the UI after service is complete. **`A02` — Torch pressure too high** * **Severity:** Warning * **Description:** Back-pressure at the welding torch extraction is above the recommended level. Capture efficiency at the source is reduced. * **Typical causes:** * Clogged or kinked torch extraction hose * Blocked torch inlet or swirl plate * Welding wear parts (nozzle, cone) worn or deformed * **What to do:** * Clean or replace the torch hose. * Inspect and clean the torch inlet and wear parts. **`A03` — Filter pressure too high** * **Severity:** Warning * **Description:** Filter differential pressure is above the warning threshold. Automatic cleaning is no longer fully sufficient. * **What to do:** * Plan a filter replacement before the critical threshold (`E08`) triggers a shutdown. * Verify the compressed air supply so cleaning runs at full effectiveness. **`A04` — No volume flow calculation possible** * **Severity:** Warning * **Description:** The device cannot currently calculate the volume flow (sensor missing / invalid, or the fan has not run long enough). IFA-compliant flow monitoring is temporarily unavailable. * **What to do:** * Let the device run for a minute and re-check. * If the warning persists, contact service — a sensor may need to be replaced or re-calibrated. **`A05` — Volume flow too low (IFA signal)** * **Severity:** Warning * **Description:** The extracted air volume has dropped below the minimum required for IFA-compliant safe operation. Capture of hazardous welding fume is no longer guaranteed. This is the IFA signal used for compliance with German occupational safety regulations for welding fume extraction equipment. * **Typical causes:** * Filter clogging (plan a replacement) * Blocked or closed extraction arms / hoods * Kinked or crushed extraction hoses * Open ducts or branches pulling away suction * **What to do:** * Clear any blockages in the extraction path. * Replace the filter if cleaning no longer recovers performance. * Verify that unused branches are closed. **`A06` — Control unit temperature too high** * **Severity:** Warning * **Description:** The internal electronics temperature is above the normal range. Prolonged operation in this state can trigger a protective shutdown. * **What to do:** * Check ambient temperature around the device. * Ensure ventilation openings on the electronics cabinet are clear. **`A07` — Motor temperature too high (warning)** * **Severity:** Warning * **Description:** The motor is running hot and is approaching the thermal trip threshold. Left unresolved, this will escalate to an `E07` fault and a forced shutdown. * **What to do:** * Reduce the duty cycle. * Check motor cooling and airflow path. **`A08` — H13 filter hours exceeded** * **Severity:** Warning * **Description:** The H13 HEPA filter has exceeded its recommended operating hours. Capture efficiency for hazardous dusts may no longer be guaranteed. * **What to do:** * Schedule a replacement of the H13 filter. * After replacement, reset the filter hour counter in the device controller. ### Clean Air Tower (Self-Cleaning / abreinigbar) #### Fault codes (FEHLERCODE register) **`E01` — Frequency inverter error** * **Severity:** Error * See `E01` under Bridge devices for the full explanation. On the Clean Air Tower this is reported on bit 1 of the `FEHLERCODE` register. **`E03` — Compressed air not connected** * **Severity:** Warning * **Description:** No compressed air is detected. The automatic filter self-cleaning cannot run, so the filter will clog rapidly and continuous safe operation cannot be guaranteed. * **What to do:** Connect compressed air at approx. 5–6 bar; check the supply line and any shut-off valves. * **Note:** If compressed air remains missing, the device escalates to the critical error `F96` below. **`E05` — Control error** * **Severity:** Error * **Description:** The internal controller reported a fault. The device may not respond to commands reliably. * **What to do:** * Power-cycle the unit. * Contact KEMPER service if the error persists. **`F96` — Compressed air not connected (critical)** * **Severity:** Error * **Description:** Compressed air has been missing for too long. Filter cleaning has been stopped and the device can no longer guarantee continuous operation. * **What to do:** * Restore compressed air supply before restarting. * Investigate why the supply was lost (leak, closed valve, failed compressor). ### Clean Air Tower (Disposable / Einweg) #### Fault codes (FAULT\_CODE register) **`E00` — Frequency inverter error** * **Severity:** Error * See `E01` under Bridge devices. On this device it is reported on bit 0 as `E00`. **`E02` — Airflow control error** * **Severity:** Error * **Description:** The airflow / VFD control loop cannot reach its setpoint. * **Typical causes:** * Clogged disposable filter * Closed damper or extraction arm * Faulty airflow sensor * **What to do:** * Replace the disposable filter. * Verify that all extraction paths are open. * If the error persists with a new filter, contact service to check the airflow sensor. **`E03` — Maintenance required** * **Severity:** Warning * **Description:** The device has reached its scheduled maintenance interval. * **What to do:** Book a service visit to replace wear parts and keep performance within specification. **`E04` — Motor temperature too high** * **Severity:** Warning * **Description:** The motor is running hot. Continued operation can damage the winding insulation. * **What to do:** * Reduce load and let the motor rest. * Check cooling openings and airflow path. * If unresolved, this escalates to a motor protection shutdown. **`E07` — Modbus error** * **Severity:** Error * **Description:** Communication fault on the internal Modbus bus between the controller and sub-components. Sensor data may be invalid and commands may not reach sub-components. * **What to do:** * Check bus cabling, terminators and addressing. * Power-cycle the device. * Contact service if the error returns. **`E12` — Airflow too low** * **Severity:** Error * **Description:** Measured airflow is below the required minimum. Capture of welding / grinding dust is no longer guaranteed. * **What to do:** * Replace the disposable filter. * Check the extraction hose for kinks and blockages. * Verify extraction arms and hoods are in the correct position. ### AirDome #### Fault codes (FEHLERCODE register) **`F90` — Frequency inverter error** * **Severity:** Error * See `E01` under Bridge devices. On the AirDome this is reported on bit 0 as `F90`. **`F94` — Critical filter pressure** * **Severity:** Error * **Description:** Filter differential pressure has exceeded the critical threshold. Airflow is severely restricted and the filter may rupture. * **What to do:** * Stop operation and replace the filter immediately. * Verify compressed air is connected so self-cleaning can run after the new filter is installed. **`F95` — Control error** * **Severity:** Error * **Description:** The internal controller reported a fault. The device may not respond to commands reliably. * **What to do:** * Power-cycle the unit. * Contact KEMPER service if the error persists. **`F96` — Compressed air not connected** * **Severity:** Warning * **Description:** No compressed air is detected. The automatic filter self-cleaning cannot run, so the filter will clog faster than normal. * **What to do:** Connect compressed air at approx. 5–6 bar. #### Warning codes (WARNING register) **`SER` — Maintenance overdue** * **Severity:** Warning * **Description:** Scheduled maintenance is overdue. * **What to do:** Book a service visit to keep the AirDome within its specified extraction performance and filter capture efficiency. **`A03` — Filter pressure too high** * **Severity:** Warning * **Description:** Filter differential pressure is in the upper warning band. * **What to do:** Plan a filter change soon to avoid reaching the critical threshold `F94`. **`A04` — No flow rate calculation** * **Severity:** Warning * **Description:** Airflow cannot currently be calculated (sensor missing / invalid, or the fan has not been running long enough). IFA-compliant flow monitoring is temporarily unavailable. * **What to do:** * Let the device run for a minute and re-check. * Contact service if the warning persists after a restart. ### VacuFil 125 The VacuFil 125 currently reports its fault code as a single numeric value without a documented bitmask decoding in KEMPER Connect. A value of `0` means "no fault"; any non-zero value should be resolved with the device's on-unit display and, if needed, KEMPER service. * **What to do on non-zero fault:** * Note the raw fault code value shown in the KEMPER Connect UI. * Read out additional details from the device's local display. * Contact KEMPER service with both the raw code and the device serial number. ### Unknown or undocumented codes If a device reports a bit that is not listed in this document, KEMPER Connect will display it as: * `Exx — Unknown error (bit x) — Contact service` (red), or * `Wxx — Unknown warning (bit x) — Check status` (amber). This usually happens after a firmware update that adds new diagnostic bits. In that case: * Note the exact code (for example `E11`) and device serial number. * Capture a screenshot of the dashboard if possible. * Contact KEMPER service so the new code can be documented and added to KEMPER Connect. ### Severity summary At a glance: #### Critical — stop and act immediately * `E01` / `E00` / `F90` — Frequency inverter error * `E03` / `E04` — Main contactor / motor protection (Bridge devices) * `E05` / `E06` — Voltage supply / control unit (Bridge devices) * `E07` — Motor temperature too high (Bridge devices) * `E08` / `F94` — Filter pressure critical * `E09` — Dust collection bin open * `E10` / `F96` (Clean Air Tower) — Compressed air not connected * `E02` / `E12` (Clean Air Tower Einweg) — Airflow control / airflow too low * `E07` (Clean Air Tower Einweg) — Modbus error * `F95` — Control error (AirDome) #### Plan and act soon * `A01` / `SER` — Service overdue * `A02` — Torch pressure too high * `A03` — Filter pressure too high (warning band) * `A05` — Volume flow too low (IFA signal) * `A06` — Control unit temperature too high * `A07` / `E04` (Clean Air Tower Einweg) — Motor temperature warning * `A08` — H13 filter hours exceeded * `E03` (Clean Air Tower) / `F96` (AirDome) — Compressed air not connected (warning) * `E03` (Clean Air Tower Einweg) — Maintenance required #### Transient / informational * `A04` — No volume flow / flow rate calculation possible * `E02` — Modbus communication error (Bridge) — usually resolved by checking cabling ### Getting support When contacting KEMPER service for an error: * Provide the full code (for example `E07`, `F94`, `SER`) and the device serial number. * Note the device type and where it is installed. * Describe any recent events — new installation, filter change, firmware update, power outage. * List the steps already tried from the "What to do" sections above. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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