--- title: "Siber DF EVO" description: "Siber DF EVO 1–4 via the DFEVORFRS485 RF-RS485 gateway on Modbus RTU: 7 fan speeds, 4 temperatures, airflow, bypass and filter status in TapHome." url: "https://taphome.com/en/compatibility/siber-df-evo/" language: en lastmod: 2026-10-08 generator: hugo ai: topics: ["modbus-rtu","air-recovery","rs485","heat-recovery","ventilation","bypass"] questions: ["How to integrate Siber DF EVO with TapHome?","What does the Siber DF EVO TapHome template control?","How to connect Siber DF EVO via Modbus RTU to TapHome?","How to monitor filter status on Siber DF EVO via TapHome?","What ventilation speeds are available on the Siber DF EVO template?","How does the Siber DFEVORFRS485 RF-RS485 gateway work?"] --- # Siber DF EVO Communication: Modbus RTU - [Siber DF EVO Product Page](https://www.siberzone.es/landings/evo/en/) - [Siber Official Website](https://www.siberzone.es) The Siber DF EVO is a double-flow heat recovery ventilation unit (HRV/ERV) for residential applications, available in four models: DF EVO 1, 2, 3 and 4. The unit communicates wirelessly with the Siber DFEVORFRS485 RF-RS485 gateway, which converts the RF signal to Modbus RTU over RS-485 for integration with TapHome. The TapHome template provides ventilation speed control with 7 positions, four temperature sensors (indoor, outdoor, supply, exhaust), airflow measurements, bypass position, defrost status, and filter lifecycle management. ## Hardware connection The Siber DF EVO unit does not have a direct RS-485 connection. Communication requires the **DFEVORFRS485** gateway (sold separately), which pairs wirelessly with the ventilation unit and exposes Modbus RTU registers over a wired RS-485 bus. ### Gateway setup 1. Connect the DFEVORFRS485 gateway to the RS-485 bus (A+, B-, GND) and to TapHome Core 2. Pair the gateway with the DF EVO unit following the Siber pairing procedure — during pairing, register H:41003 reports value 254 ("Binding mode active") 3. Once paired, the gateway bridges all sensor data and control commands between the ventilation unit and the Modbus bus > [!WARNING] > The RF communication between the unit and the gateway has a timeout — if no communication is received for 30 minutes, register H:40101 reports an error. Ensure the gateway is within range of the ventilation unit. ## Configuration ### Modbus connection parameters | Parameter | Value | |-----------|-------| | **Baud rate** | 19200 | | **Parity** | Even | | **Stop bits** | 1 | | **Data bits** | 8 | | **Slave ID** | 1 (default, configurable) | ### Error monitoring The module ReadScript monitors register H:41003 for error codes and reports them in TapHome: | Code | Meaning | TapHome severity | |------|---------|-----------------| | 1 | Unspecified fault | Error | | 2 | Emergency stop | Warning | | 3 | Supply fan 1 error | Error | | 4 | Sensor X22 error | Error | | 5 | Sensor X23 error | Error | | 6 | Sensor X21 error | Error | | 7 | Sensor X20 error | Error | | 8 | Fan 2 error | Error | | 254 | Binding mode active | Warning | | 255 | Device identification active | Warning | ## Device capabilities ### Ventilation speed control **Ventilation Speed** (H:41000 read / H:41500 write) is a multi-value switch with 7 positions: - **Off** — unit stopped - **Minimum** — absolute minimum (away mode) - **Speed 1** — low - **Speed 2** — nominal - **Speed 3** — high - **Auto** — automatic speed regulation - **Boost** — maximum airflow The read register uses complex mapping (temporary overrides, away mode) that the template normalizes to the 7-position switch. The write register accepts the position index directly. ### Fan speed monitoring Two sensors report the actual fan speed as a percentage (0–100%): - **Inlet Fan Speed** (H:41002) — supply fan speed - **Exhaust Fan Speed** (H:41001) — exhaust fan speed ### Temperature monitoring Four temperature sensors read LittleEndianFloat values across two holding registers each: - **Indoor Temperature** (H:41005–41006) — indoor air temperature - **Outdoor Temperature** (H:41007–41008) — outdoor air temperature, also used for anti-ice protection - **Supply Temperature** (H:41011–41012) — temperature of fresh air supplied to the home after heat recovery - **Exhaust Temperature** (H:41009–41010) — temperature of stale air exhausted from the home A value of NaN indicates the sensor is unavailable. Values below -273°C indicate a sensor problem. ### Airflow measurement Two sensors read the volume flow rate in m³/h as LittleEndianFloat values: - **Inlet Airflow** (H:41019–41020) — supply air volume flow - **Exhaust Airflow** (H:41021–41022) — exhaust air volume flow > [!NOTE] > Airflow sensors may not be available on all internal board models (VMD-02RPS78/66). Special value 0x7FFF indicates "not available". ### Bypass and defrost status - **Bypass Position** (H:41016) — bypass damper position as percentage: 0% = closed, 100% = open. Values above 120% indicate an error. The bypass opens automatically based on indoor/outdoor temperature conditions for free-cooling - **Defrost** (H:41015) — anti-ice protection status. The unit engages progressive defrost at low outdoor temperatures ### Filter management **Filter Status** (H:41042) displays the remaining filter life as an inverted percentage (100% = new, 0% = needs replacement). The ReadScript also monitors H:41014 and adds a warning when the filter is dirty. Two service attributes provide additional detail: - **Days Until Filter Replacement** (H:41040) — days remaining before the filter should be cleaned or replaced - **Filter Replacement Interval** (H:41041) — configured interval in days A **Reset Filter Timer** service action (writes H:42000) resets the filter counter after cleaning or replacement. > [!TIP] > Siber recommends checking filters every 3 months, cleaning every 6 months, and replacing at least once a year. ### Additional capabilities The DF EVO also exposes registers for indoor and outdoor humidity (requires optional DFEVOHR wireless sensor), CO2 level (requires optional DFEVOCO2 sensor), air quality index, preheater and post-heater power levels, and per-speed fan percentage configuration. Temporary speed override timers (up to 18 hours) and frost protection setpoints are also available via Modbus. These can be added in a future template update. ## Troubleshooting ### No Modbus communication 1. Verify the DFEVORFRS485 gateway is powered and paired with the ventilation unit 2. Check the RS-485 wiring between the gateway and TapHome Core (A+, B-, GND) 3. Confirm TapHome is configured for 19200 baud, even parity, 1 stop bit 4. Check register H:40101 — value 1 indicates RF communication loss between the gateway and the unit (no communication for 30+ minutes) ### Sensor readings show NaN or extreme values 1. NaN indicates the sensor is unavailable — check the physical sensor connection inside the unit 2. Values below -273°C indicate a sensor hardware problem 3. Airflow values of 0x7FFF mean the flow sensor is not available on the installed board model ### Filter warning in TapHome 1. The warning "Filter je spinavy" (Slovak for "filter is dirty") appears when H:41014 reports the filter is dirty 2. Clean or replace the filter following the Siber maintenance procedure 3. After replacing the filter, use the **Reset Filter Timer** service action in TapHome to clear the warning and reset the counter ## Available devices Siber DF EVO Module Bypass Position Analog Input Read-only Heat exchanger bypass damper position — 0% closed, 100% open Register: H:41016 UInt16 Unit: % numeric Filter Status Analog Input Read-only Air filter remaining life — 100% new, 0% needs replacement; warns when filter is dirty Register: H:41042 UInt16 Unit: % numeric Service Attributes | | |-------------------------------| | Days Until Filter Replacement | | Filter Replacement Interval | Service Actions | | |--------------------| | Reset Filter Timer | Defrost Reed Contact Read-only Anti-ice protection status — active when low outdoor temperatures require defrost Register: H:41015 Bool Indoor Temperature Temperature Sensor Read-only Register: H:41005 LittleEndianFloat Unit: °C numeric Inlet Airflow Variable Read-only Supply air volume flow rate in m³/h Register: H:41019 LittleEndianFloat Unit: m³/h numeric Exhaust Airflow Variable Read-only Exhaust air volume flow rate in m³/h Register: H:41021 LittleEndianFloat Unit: m³/h numeric Ventilation Speed Multi-value Switch Ventilation speed selector — Off, Minimum, Speed 1–3, Auto, Boost Register: H:41000 → H:41500 UInt16 multi-value Values / States: ${level\_0Of4} · Minimum · Automatika · Boost Inlet Fan Speed Variable Read-only Actual supply fan speed as percentage Register: H:41002 UInt16 Unit: % numeric Exhaust Fan Speed Variable Read-only Actual exhaust fan speed as percentage Register: H:41001 UInt16 Unit: % numeric Outdoor Temperature Temperature Sensor Read-only Register: H:41007 LittleEndianFloat Unit: °C numeric Supply Temperature Temperature Sensor Read-only Temperature of fresh air supplied to the home after heat recovery Register: H:41011 LittleEndianFloat Unit: °C numeric Exhaust Temperature Temperature Sensor Read-only Temperature of stale air exhausted from the home before heat recovery Register: H:41009 LittleEndianFloat Unit: °C numeric **Connection:** Modbus RTU • 19200 baud• 8E1 • Slave ID: $\[SlaveId] Possible improvements (24) - H:41004 Remaining Override Time — Minutes remaining for temporary speed override; only valid when actual speed = 11/12/13 (timer override modes) - H:41013 Preheater Level — 0%=off, 100%=maximum, EFh=not available; preheater power level for anti-ice protection - H:41017 Indoor Humidity — Relative humidity %, requires optional wireless humidity sensor (DFEVOHR); EFh=not available - H:41018 Outdoor Humidity — Not available on VMD-02RPS78/66 models (value=EFh) - H:41023 Air Quality — 0%=poor, 100%=excellent; not available on VMD-02RPS78/66 (value=EFh); requires optional sensor - H:41024 Air Quality Basis — Bitmask: bit0=VOC, bit1=CO2, bit2=RH; not available on VMD-02RPS78/66 - H:41025 CO2 Level — ppm, requires optional CO2 sensor (DFEVOCO2); 7FFFh=not available - H:41026 Post Heater Level — 0%=off, 100%=maximum, EFh=not available; post-heater power level - H:41027 Speed Capability Bits — Bitmask: preheater/postheater available, night/timer/auto/boost/OFF capable, speed 4–10 capable - H:41501 Override Time Speed 1 — Write-only, minutes; triggers temporary override to speed 1 (max 18h = 1080 min) - H:41502 Override Time Speed 2 — Write-only, minutes; triggers temporary override to speed 2 (max 18h = 1080 min) - H:41503 Override Time Speed 3 — Write-only, minutes; triggers temporary override to speed 3 (max 18h = 1080 min) - H:42001 Standby Speed Supply — R/W, 0–40%, supply fan speed in standby mode - H:42002 Standby Speed Exhaust — R/W, 0–40%, exhaust fan speed in standby mode - H:42003 Low Speed Supply — R/W, 0–80%, supply fan speed at low setting - H:42004 Low Speed Exhaust — R/W, 0–80%, exhaust fan speed at low setting - H:42005 Medium Speed Supply — R/W, 0–100%, supply fan speed at medium setting - H:42006 Medium Speed Exhaust — R/W, 10–100%, exhaust fan speed at medium setting - H:42007 High Speed Supply — R/W, 0–100%, supply fan speed at high setting - H:42008 High Speed Exhaust — R/W, 10–100%, exhaust fan speed at high setting - H:42009 Frost Protection Preheater Setpoint — R/W, FLOAT, -20–50°C; temperature setpoint for frost protection preheater activation - H:42011 Preheater Setpoint — R/W, FLOAT, -20–50°C; preheater target temperature setpoint - H:42013 Free Ventilation Heating Setpoint — R/W, FLOAT, 0–30°C; bypass heating mode activation temperature - H:42015 Free Ventilation Cooling Offset — R/W, FLOAT, 1–10 K; bypass cooling mode temperature offset ## Sources - Siber EVO 3&4 Installation and User Manual [multikomplex.hu](https://multikomplex.hu/uploads/documents/Siber/Telepitesi-es-hasznalati-utmutato/Telepitesi_utmutato_Siber_-_DF_EVO_3-4_EN_v12.0324.pdf) 2026-03-21 [PDF](https://taphome.com/compatibility/devices/siber-df-evo/installation-manual-3-4.pdf) - VMD-02RPS66 VMD-02RPS78 Modbus Registers Overview (Airios) 2026-03-21 [PDF](https://taphome.com/compatibility/devices/siber-df-evo/vmd-modbus-registers.pdf) - Siber DF EVO 1 Technical Datasheet [www.aerismos.gr](https://www.aerismos.gr/images/products/p-249-2995.pdf) 2026-03-21 [PDF](https://taphome.com/compatibility/devices/siber-df-evo/datasheet-df-evo-1.pdf) - Siber DF EVO Product Page [www.siberzone.es](https://www.siberzone.es/landings/evo/en/) 2026-03-21 ## Related Documentation - [Modbus Integration](https://taphome.com/en/compatibility/modbus-guide/) - [Modbus](https://taphome.com/en/docs/integration/modbus/) - [Simple configuration using templates](https://taphome.com/en/docs/integration/modbus/templates/) - [Modbus scripts and prefetch](https://taphome.com/en/docs/script/modbus-scripts/) - [Modbus functions](https://taphome.com/en/docs/script/modbus/) - [Modbus data types](https://taphome.com/en/docs/script/modbus-data-types/)