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Flow 40

A ductless decentralised HRV system for efficient indoor air exchange with concealed in-wall installation. Now also available with grilles exit on the side of the window frame, even more invisible.

VMC a incasso Helty Flow 40
Helty Flow 40 prodotto
Helty Flow40 tecnico
Helty Flow 40 uscita in luce prodotto
helty flow 40 uscita in luce esploso
Helty Flow 40 prodotto
Helty Flow40 tecnico
Helty Flow 40 uscita in luce prodotto
helty flow 40 uscita in luce esploso

The recessed ventilation system that is there but out of sight

An invisible HRV, which combines excellent air exchange and purification performance with zero footprint: “disappearing” inside the wall, Flow40 does not require piping or false ceilings and leaves only the front cover visible.Single-room ventilation allows you to adjust functions and performance based on the actual needs of each room, ensuring efficient system management and personalised comfort.

Soluzione invisibile - Design minimal The invisible solution!
Recupero calore TUV certified 91% heat recovery
Filtrazione aria Advanced air filtration
Sensore CO2 VOC Indoor air quality control sensors

Price upon request

With Flow40 we can integrate an air exchange system even with no space available for ducting and technical compartments. The ductless design requires no air network adjustment, simplifying the commissioning and long-term management of the system.

Alessio C. - technical manager, F.lli Beltrame

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Flow40 offers all the benefits of Heat Recovery Ventilation, simplifying the design and minimising the aesthetic impact, dimensions and maintenance.

Ideal for renovations and energy upgrades

The use of prefabricated components and the absence of air distribution networks makes this wall-recessed HRV system particularly easy to design and versatile to install during residential renovation or energy upgrading.The Flow40 ventilation system can be installed on walls of variable thickness (minimum 335 mm), both with plaster finish and with insulation.

Helty Flow 40 hrv for renovations
Comfort indoor with Helty hrv Flow 40

Optimal thermal and acoustic comfort

The special cross-flow enthalpy heat recovery system allows Flow40 to recover up to 91% of the heat contained in the extracted air flow, avoiding the energy losses that would occur with the introduction of cold air. By also recovering some of the latent moisture content, it ensures the intake air is never too dry.

Acoustic comfort is assured thanks to advanced facade noise abatement and sound pressure levels of just 18dB at first speed. The absence of air ducts avoids acoustic bridges and noise transfer between rooms.

Protection against condensation, mould and pollutants

The HRV unit is also equipped as standard with a hygrometer for continuous monitoring of relative room humidity allowing for an automatic and more efficient regulation of forced ventilation to combat condensation and mould.

The CO2 and VOC sensor and monitoring app (available in the Pure version) mean extensive control of indoor air quality at any time of the day.

balduina 142 roma hrv helty flow40
Helty Flow40 windows-side set

New Flow 40 windows-side

Helty Flow 40 HRV with grilles exit on the side of the window frame is the innovative concealed solution that is even more invisible and discreet, thanks to the possibility of managing the grille exits directly in the window shoulder.

A system that has no visible impact on the facade, preserving the integrity of any type of building. Flow 40 with light exit is an interesting and versatile option for major renovations and new construction sites in contexts that require special attention to architectural aesthetics. The system can also be planned in the construction phase alone, to be completed at a later date as required.

Technical data

Airflow m3/h 10/17/26/37/42 (1)
Airflow adjustment   4 settings + high-speed ventilation
Power consumption (2) W 3.6 - 20.0
Supply voltage V AC 230
Operating voltage V DC 24
Max. current consumption (3) A 0.17
HRV unit weight kg 4
Unit dimensions (H x L x P) mm 108 x 408 x 268
Preparatory dimensions (H x L x P)   145 x 473 x 517
Heat exchanger   enthalpy cross-counter flow
Heat recovery efficiency % 91
Sound pressure level (4) dB(A) 15/20.9/26.3/34.5
Facade noise abatement Dn,e,w dB 45
Filters   F7+G4 / G2
Energy class   A+ / A / E
SEC kWh/m2a -74.1 / -37.9 / -14.6
Filter replacement alert   indicator light on unit
1. In high-speed ventilation mode2. excluding UV lamp3. With 230 V AC supply voltage4. Measured on a 30 m² semi-anechoic environment at a distance of 3 m
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Frequently asked questions

Installing a concealed CMV system requires a creating a recess in the perimeter wall where the ventilation system will be positioned, which needs to served by the power supply. The hole dimensions are available in a reserved area.

Flow40 concealed CMVs require a perimeter wall with a minimum thickness of 335mm. Flow70 and Flow100 systems require perimeter walls with a minimum thickness of 460mm.

An enthalpy heat exchanger recovers both the sensible thermal energy (the heat) and the latent energy (the humidity) from the air flow. It has the advantage of offering better overall energy efficiency without over-drying the incoming air.

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Certified quality and performance

The performance of the Helty ventilation systems are recognized by the Casa Clima Quality Seal and have obtained the SIMA and BioSafe validations

  • CasaClima_VMC_Prodotto_Qualita
  • Biosafe.it Certification