Video summary

VMC simple flux Hygro B : le système de ventilation le plus pourri en France !?

Main summary

Key takeaways

Product Review

Product(s) reviewed / compared

The video compares three French single-flow MVHR (mechanical ventilation with heat recovery) / humidity-controlled ventilation systems that use fiber-optic (hygro) regulation concepts, focusing on:

  • Vent/housing airflow regulation approach
  • Certification
  • Cost
  • Installation
  • Performance
  • Maintenance

Main models

  1. Atlantique Hibrocosi (aka Atlantique Igro Cosi) — entry / best-seller type; regulation mostly at the vent.
  2. SCP Octeo Dhu — mid-range; regulation inside the unit using humidity sensors; not “igro”-certified in France (for low-energy use), though it works similarly.
  3. Renson Sbox 3.0 — top-of-the-range “full features” unit; certified (igro), with advanced sensing + app control.

Key points (unique) mentioned about the systems

1) Regulatory / market context (sets the critique baseline)

  • In France, most residential ventilation is single-flow MVHR.
  • The regulation is largely based on 1982 rules (continuous ventilation + minimum sanitary flows), with 1983 allowing reduced flows when humidity is low.
  • The video claims this 1983 approach focuses on humidity, not indoor air quality, which can lead to:
    • Too-low flows when the home is dry
    • Insufficient removal of pollutants
  • The reviewer also notes NF DTU and RE 2020 (since 2023) changes, but says the framework still largely follows the older humidity logic.

Model-by-model extraction

A) Atlantique Hibrocosi / Atlantique Igro Cosi (best-selling, but criticized)

Main design / how it works

  • Has a kitchen inlet plus up to 6 inlets for other sanitary rooms.
  • Unused inlets can be capped with a plug without a seal.
  • Uses an 80 mm inlet network and a 160 mm roof outlet.
  • The system is “inseparable” from its vent: most regulation happens in the vent, not in the unit.
  • The machine tries to regulate pressure, but the host/vent behavior doesn’t reliably produce correct flow rates.
  • No meaningful sensors inside the fan/unit: the reviewer states there is no speed sensor, humidity sensor, or pressure sensor in the fan assembly.
  • Humidity control is essentially a spring/tab + vent flap mechanism:
    • Humid vs dry positions move a tab to change the vent opening.
    • The vent is described as having high pressure drop, very small openings, and noisy airflow characteristics.

User experience / performance claims

  • The reviewer reports measured airflow at vents:
    • In large houses: not enough airflow
    • In small houses / apartments: too much airflow
  • They claim it’s hard/impossible to properly balance/adjust because regulation is limited to that vent mechanism.
  • Frequent issues reported:
    • Vents found nearly closed
    • Very low flows, even on relatively new machines (one installed < 1 year)
    • One case where it couldn’t be removed because it was “not working,” and humidity was everywhere
  • The reviewer specifically points to installation with flexible ducts, recommending looking into semi-rigid vs flexible ducts.

Maintenance

  • Requires access to the unit; often installed in attics and not designed for easy service.
  • Maintenance complexity includes pulling out a flap during cleaning.

Cost / configuration

  • The installer reportedly sets nothing: no T1–T7 settings or user-adjustment; it’s “plug it in and leave.”

Pros (mentioned implicitly / minor)

  • Widely sold / common French bestseller.
  • Simple installation: electrician connects neutral/phase/earth only.

Cons (major)

  • Poor regulation: depends heavily on ductwork length and conditions.
  • Unreliable airflow across different house sizes.
  • Reviewer “advises against” it and says they never offer/install it at Objectif 15.

Overall verdict for this model

  • Considered to have no regulation worthy of the name and poor indoor-air outcomes due to a humidity-only approach.

B) SCP Octeo Dhu (regulated unit, but not “igro” certified in France)

Main design / how it works

  • Similar format to Atlantique mechanically; can be mounted on a string, but can also be installed flat (reviewer prefers flat for maintenance/stability).
  • Reviewer states: vent itself is not where regulation happens; vents are described as simple plastic with no regulation.
  • Regulation occurs inside the machine using sensors:
    • Two humidity sensors (kitchen area behind kitchen inlet + main bathroom inlet)
    • Possibly CO2 sensor (mentioned as “potentially a CO2 sensor” in the kitchen area)
  • Has an electronic control board designed for configuration:
    • Installer can set parameters (operating modes, housing sizes)
    • Protected wiring/cabling access
  • Maintenance-friendly feature: a domino connector allows the machine to shut off during maintenance.

User experience / performance claims

  • Reviewer likes it and calls it a good machine, positioned as a better alternative with actual regulation.
  • Multi-speed fan behavior:
    • Normal speed for base airflow
    • Higher speed when humidity is higher
    • “Ramp” between ~60 and 90% humidity, reaching full speed at 90%
    • Low speed at ≤ 60%

Certification / compatibility constraints (key drawback)

  • Not certified as low-energy “igro” (in France), so:
    • Not allowed for renovation installs in the scenario described (or at least, the video says renovation would not be allowed)
    • In new construction, it’s implied it also cannot be used in the usual scheme
  • A parallel SCP model exists: Octeo-igro, described as vent-regulated like the Atlantique; Octeo Dhu here is the internally regulated one.

Financial / subsidy implications

  • Because it’s not “igro” in France, the video claims you may lose:
    • 55% VAT reduction for renovations
    • possibly some renovation subsidies
  • Reviewer suggests this can depend on timing and real-world energy-audit coding.

Pros

  • Proper internal regulation (not vent-only).
  • Sensor-based (humidity sensors; possible CO2).
  • Better airflow behavior with “ramp” fan control.
  • More maintainable than Atlantique due to intended access/configuration.

Cons

  • Regulatory/certification issue in France: not eligible for “igro” low-energy scheme use.
  • Potential loss of VAT/subsidies.

Overall verdict for this model

  • “Better than” the vent-self-regulating type, but certification/scheme limits reduce practical attractiveness in France.

C) Renson Sbox 3.0 (top range, app-controlled, certified)

Main design / how it works

  • “Top-of-the-range” aimed at renovations.
  • Uses vent-by-vent dampers and central electronics:
    • For each location/connection, the video describes fixed dampers controlled by the machine
    • Dampers connect via RJ45; the machine “recognizes” each damper’s placement
  • Sensors and flow regulation:
    • Always has a CO2 sensor (claimed first among these three in the video)
    • Humidity/air-quality sensors in bathroom and kitchen areas:
      • Bathroom: humidity sensor (described as detecting VOCs / “volatile organic compounds”)
      • Kitchen: humidity sensor + CO2 sensor
    • A flow sensor is included; the machine forces required flow rates
  • Uses an electronic regulator and motor/butterfly valve to open/close and maintain targets.

Ventilation strategy claims

  • Bedroom CO2 regulation is described as possible (framed as an option rather than strictly mandated):
    • Shower increases humidity → system speeds up there
    • After shower, bedroom slows as humidity dissipates
    • Bedroom “takes over” based on CO2 generated during sleep

Connectivity / apps / control

  • Two apps:
    • Installer app for commissioning (house size, number of rooms, adjust flow rates)
    • User app for daily control:
      • Manual boost per vent up to 200% for up to 30 minutes
      • Also allows boosts around 120–130%
      • Absence mode (lower rates)
      • Summer mode that cools at night using internal temperature sensing
  • Fault handling:
    • App warns on overheating or faults
    • Error codes shown via app

Hardware / maintenance

  • Communication via an antenna to Wi‑Fi/router and the phone app (described as communication “via Wii with an antenna”).
  • Modular maintenance:
    • Parts like the circuit board and fan module can be replaced without fully replacing the system
    • Cleaning and reconfiguration/calibration via the app

Installation constraints

  • Reviewer says it cannot be installed on strings (must be mounted on a surface).
  • Avoid cold areas like attics unless placed inside an insulated box.

Certification / subsidies

  • Has igro approval, making it suitable for:
    • New construction and renovation
    • Eligibility for 55% VAT (as stated)
  • Flow capacity claim example:
    • “135 m³/h in the kitchen” handled without issue (assuming correct network installation)
  • If the ducts/network are blocked or improperly installed, it cannot be commissioned (installer responsibility).

Cost (numerical)

  • Module cost around €500, plus additional equipment depending on number of rooms.
  • Total equipment typically around €1000–€1500 when installed (as described).

Pros

  • Most advanced regulation and sensing → strongest confidence in indoor air quality among compared models.
  • Vent-by-vent control and forced compliance with target flow rates.
  • Always-on CO2 sensing (per the video).
  • App control: boosts, modes, overheating protection.
  • Strong service approach: reviewer claims quick replacements and minimal major defects.

Cons

  • Expensive.
  • Requires good duct/network installation to commission successfully.

Overall verdict for this model

  • Strongly recommended as the most capable system for indoor air quality assurance, and the reviewer’s favorite.

Comparisons & conclusions drawn in the video

  • The reviewer frames the three systems as having three “technologies”:
    1. No real internal regulation (Atlantique; vent/spring only)
    2. Internal electronic regulation with sensors, but not France igro-approved for the low-energy scheme (Octeo Dhu)
    3. Full internal regulation with:
      • vent-by-vent dampers
      • CO2 sensing
      • flow sensing / target forcing
      • app control (Renson Sbox 3.0)

Final stance

  • Atlantique: does not meet quality criteria → Objectif 15 will not offer/install.
  • SCP Octeo Dhu: liked, but certification/subsidy constraints limit practical use.
  • Renson Sbox 3.0: recommended as best for indoor air quality and controllability.

Main “pros vs cons” summary (quick)

Atlantique Igro Cosi

  • Pros: very common/best-selling; simple plug-in; straightforward installer wiring.
  • Cons: vent-only regulation; airflow often wrong by house size; ductwork dependency; low reliability; reviewer sees poor air-quality outcomes.

SCP Octeo Dhu

  • Pros: internal sensor-based regulation; multi-speed “ramp”; more maintainable; configurable.
  • Cons: not France “igro” low-energy certified → subsidy/VAT eligibility concerns.

Renson Sbox 3.0

  • Pros: advanced sensing (incl. CO2), forced flow control, vent-by-vent dampers; app control; fault reporting; modular maintenance; eligible via igro approval for renovation/new (per video).
  • Cons: higher cost; requires good duct-network installation; not for string mounting.

Numerical details explicitly mentioned

  • Octeo Dhu humidity “ramp”: ~60–90% humidity
  • Renson Sbox 3.0:
    • Module cost around €500
    • Total equipment typically €1000–€1500
    • Kitchen capacity example: 135 m³/h
    • App boosts: up to 200% for 30 minutes; also 120–130%
  • No star ratings or numeric scores beyond the above.

Speakers / contributor views

  • The video appears voiced by the main presenter from Objectif 15 (single primary speaker).
  • No distinct secondary speakers with clearly separate opinions are identified in the subtitles.

Overall verdict / recommendation (concise)

Based on the video:

  • Atlantique Igro Cosi (vent self-regulating by humidity flap) is considered unreliable and inadequate for indoor air quality, so the reviewer won’t install it.
  • SCP Octeo Dhu is viewed as technically better due to proper internal sensor regulation, but has France certification/subsidy limitations.
  • Renson Sbox 3.0 is presented as the best overall choice: most advanced regulation (including CO2 + flow sensing), vent-by-vent control, strong app functionality, and igro approval—despite being more expensive.

Original video