Reventon HC-3S 230V water unit heater – AC motor, 3-speed fan, EPP housing
The Reventon HC-3S series is a range of water unit heaters with an alternating-current motor (230 V / 50 Hz) and a 3-speed fan, available in 8 sizes with nominal heat outputs ranging from 17.2 kW (HC15-3S) to 69.2 kW (HC80-3S) at water temperatures of 90/70 °C and an air temperature of 0 °C. The housing is made of 100% recyclable expanded polypropylene (EPP), which dampens operating noise. The fan has an IP 54 protection rating in compliance with European Directive 2009/125/EC (ErP 2015). Manufacturer's warranty: 24 months. Manufactured by Reventon Group Sp. z o.o. (Poland). Distributed in Italy by Krollit, an official Reventon distributor since 2007, Monteforte Irpino (AV), tel. +39 0825-1494022.
- Power supply: 230 V / 50 Hz, single-phase
- Nominal heat output* (3rd speed): from 17.2 kW (HC15-3S) to 69.2 kW (HC80-3S)
- Heat output range** (min–max): from 1.55 kW to 91.5 kW
- Maximum airflow (3rd speed): from 1,500 m³/h (HC15-3S) to 5,000 m³/h (HC50-3S)
- Maximum air throw: from 10 m (HC15-3S) to 24 m (HC50-3S)
- Fan: 3 fixed speeds, IP 54 protection rating
- Housing: EPP (expanded polypropylene), 100% recyclable
- Heat exchanger: 1, 2 or 3 rows depending on the model
- Water connections: 3/4"
- Maximum heating medium temperature: 120 °C
- Maximum operating pressure: 1.6 MPa
- Noise level (3rd speed, at 5 m): from 53 dB (HC15-3S) to 66 dB (HC50-3S)
- Net weight: from 10 kg (HC15-3S) to 22.5 kg (HC80-3S)
- Manufacturer's warranty: 24 months
Who uses the HC-3S series and what for
The HC-3S series is used in industrial and commercial facilities equipped with a central hot-water heating circuit. HVAC installers and technical managers of production halls, logistics warehouses and commercial halls choose the HC-3S series to heat large-volume spaces with heights of up to 8–10 m. The EPP housing and the fan's IP 54 protection rating also allow use in environments with high relative humidity, such as greenhouses, vehicle workshops and garages. The 3-speed fan allows the airflow to be adapted to the room's requirements without additional accessories.
Its place in the Reventon range
The HC-3S series forms part of Reventon's range of water unit heaters with alternating-current motors and 3 fixed speed settings. Alongside the HC-3S series, Reventon offers the HC-EC series, equipped with an electronically commutated (EC) motor with continuously variable speed control, intended for systems requiring precise airflow modulation and integration with building management systems (BMS). Krollit has been an official Reventon distributor since 2007 and distributes the entire range in Italy. For help choosing a model: +39 0825-1494022.
Krollit logistics and support
Units are dispatched within 5–9 working days (7 days for Southern Italy). Spare parts and accessories are dispatched within 3–5 working days from Krollit's warehouse. Italian-language customer support is available for technical documentation (data sheets, EC declaration, installation instructions), model selection and accessory order management. Krollit has been an official Reventon distributor since 2007, Via Padule 6 – 83024 Monteforte Irpino (AV).
Who the HC-3S series is for
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Application
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Suitability
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Reason
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Industrial halls and mechanical workshops
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Suitable
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Water-based heating for large-volume spaces; air throw of up to 24 m for uniform air distribution
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Logistics warehouses and storage centres
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Suitable
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IP 54 protection and moisture-resistant EPP housing; airflow of up to 5,000 m³/h for spaces 8–10 m high
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Greenhouses and agricultural premises
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Suitable
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Maximum fluid temperature of 120 °C; 3 speeds to adjust airflow according to crop requirements
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Residential spaces (apartments, houses)
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Not recommended
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Sized for industrial spaces; requires a hydronic system with a boiler and 3/4" connections – standard convector heaters are more suitable for residential use
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Not recommended for: private residential spaces (apartments, studios, houses) – the HC-3S series is sized for large-volume industrial and commercial spaces and requires a central hydronic system with a boiler.
Heat output and heat exchanger
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Model
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Product code
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Heat output* [kW] 3rd/2nd/1st speed
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Heat output range** [kW]
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Heat exchanger rows
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HC15-3S
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WHHC15-3S-2402
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17.2 / 13.4 / 12.1
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1.79 – 23.3
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2
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HC20-3S
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WHHC20-3S-1759
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21.4 / 17.3 / 13.3
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1.55 – 28.4
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1
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HC30-3S
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WHHC30-3S-1760
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26.4 / 20.3 / 15.5
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1.80 – 34.9
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1
|
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HC35-3S
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WHHC35-3S-1761
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30.3 / 22.9 / 17.3
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2.14 – 40.1
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2
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HC45-3S
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WHHC45-3S-1762
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42.0 / 28.9 / 21.1
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3.21 – 55.6
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2
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HC50-3S
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WHHC50-3S-2006
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49.8 / 45.2 / 34.6
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5.00 – 65.8
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2
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HC70-3S
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WHHC70-3S-1764
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60.6 / 40.1 / 32.7
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5.00 – 80.1
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3
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HC80-3S
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WHHC80-3S-1956
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69.2 / 61.5 / 46.5
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6.96 – 91.5
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3
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Airflow and air throw
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Model
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Airflow [m³/h] 3rd/2nd/1st speed
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Maximum air throw [m]
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Water capacity [dm³]
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HC15-3S
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1,500 / 1,000 / 850
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10
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0.45
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HC20-3S
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3,200 / 2,150 / 1,350
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19
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0.65
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HC30-3S
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3,100 / 1,950 / 1,250
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18
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0.80
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HC35-3S
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2,700 / 1,700 / 1,100
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15
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1.35
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HC45-3S
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2,500 / 1,450 / 950
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14
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1.70
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HC50-3S
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5,000 / 4,200 / 2,600
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24
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1.95
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HC70-3S
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3,400 / 1,900 / 1,450
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18
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2.85
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HC80-3S
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4,200 / 3,500 / 2,300
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21
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2.85
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Motor and power supply
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Model
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Voltage [V/Hz]
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Rated current [A] 3rd/2nd/1st speed
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Rotational speed [rpm] 3rd/2nd/1st speed
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Motor power [W] 3rd/2nd/1st speed
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HC15-3S
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230/50
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0.36 / 0.22 / 0.21
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1,400 / 1,200 / 1,000
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80 / 48 / 45
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HC20-3S
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230/50
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0.82 / 0.62 / 0.41
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1,380 / 1,030 / 650
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185 / 140 / 90
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HC30-3S
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230/50
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0.82 / 0.62 / 0.41
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1,380 / 1,030 / 650
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185 / 140 / 90
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HC35-3S
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230/50
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0.82 / 0.62 / 0.41
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1,380 / 1,030 / 650
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185 / 140 / 90
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HC45-3S
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230/50
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0.82 / 0.62 / 0.41
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1,380 / 1,030 / 650
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185 / 140 / 90
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HC50-3S
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230/50
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2.05 / 1.65 / 1.40
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1,380 / 1,200 / 900
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455 / 350 / 280
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HC70-3S
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230/50
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1.08 / 0.86 / 0.70
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1,360 / 1,050 / 750
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240 / 190 / 160
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HC80-3S
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230/50
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2.05 / 1.65 / 1.40
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1,350 / 1,200 / 900
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455 / 350 / 280
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Hydraulic parameters and protection rating
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Maximum heating medium temperature
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120 °C
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Maximum operating pressure
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1.6 MPa
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Connection diameter
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3/4"
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Fan protection rating
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IP 54
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Directive compliance
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2009/125/EC (ErP 2015)
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Manufacturer's warranty
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24 months
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Acoustics and weight
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Model
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Noise level*** [dB] 3rd/2nd/1st speed
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Net weight [kg]
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HC15-3S
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53 / 47 / 45
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10
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HC20-3S
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57 / 55 / 49
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12.5
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HC30-3S
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57 / 55 / 49
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12.5
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HC35-3S
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56 / 54 / 48
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14
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HC45-3S
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56 / 54 / 48
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14
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HC50-3S
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66 / 60 / 54
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20.5
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HC70-3S
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58 / 53 / 49
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20
|
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HC80-3S
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65 / 59 / 53
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22.5
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* Heat output at water temperatures of 90/70 °C (flow/return) and an inlet air temperature of 0 °C.
** Minimum output: water 40/30 °C, air 20 °C, 1st speed – Maximum output: water 120/90 °C, air 0 °C, 3rd speed.
*** Noise level measured at a distance of 5 m from the unit.
Heating industrial halls and workshops
The HC-3S series is designed for water-based heating of large-volume industrial spaces. Maximum air throw ranges from 10 m (HC15-3S) to 24 m (HC50-3S), covering typical industrial hall widths without the need for additional terminal units. Model selection depends on the room's heating requirement, calculated according to its volume, insulation and the design outdoor temperature. For halls with ceilings above 8 m, positioning the unit at an angle is recommended to promote destratification of warm air.
Heating greenhouses and agricultural premises with high humidity
The fan's IP 54 protection rating and the EPP housing allow use in environments with water splashes and high humidity, such as horticultural and agricultural greenhouses. The maximum fluid temperature of 120 °C and the wide heat output range (1.55–91.5 kW) allow the unit size to be matched to the greenhouse volume. Using the 1st speed during daytime reduces air movement around delicate crops; the 3rd speed during cold periods ensures a rapid heating response.
Heating logistics warehouses and commercial halls
In logistics warehouses with high-density racking, the airflow (up to 5,000 m³/h for the HC50-3S) allows heat to be distributed over a large area even in the presence of physical obstacles. Connection to Reventon accessories – the HC manual thermostat, HMI programmable thermostat or HMI WiFi controller – enables automatic heating management with weekly programming, reducing energy consumption outside operating hours.
Frequently asked questions
How do you choose the right HC-3S model for your building?
Sizing is based on the room's heating requirement, expressed in kW and calculated according to its volume, wall and ceiling insulation, and the design outdoor temperature. The model is selected by comparing this requirement with the nominal heat output at the 3rd speed (based on water at 90/70 °C and air at 0 °C).
Adding a 20% margin to the calculated requirement is recommended to compensate for unforeseen heat losses and ensure a rapid heating response during preheating. Reventon provides a heat load calculator on its website. Krollit provides technical support in Italian for sizing: +39 0825-1494022.
Does the HC-3S series operate independently or require a separate boiler?
The HC-3S series is a terminal unit for central hot-water heating systems (water unit heater). It does not generate heat independently: it must be connected to a hydronic circuit containing hot fluid (water or antifreeze solution), supplied by a boiler, a heat pump system or another heat source.
Connection is via two 3/4" water connections. Installing shut-off valves and a Y-strainer at the inlet is recommended. The maximum permitted operating pressure is 1.6 MPa and the maximum fluid temperature is 120 °C. Where there is a risk of freezing, use a propylene glycol or ethylene glycol antifreeze solution compatible with the circuit materials.
How far does the HC-3S series distribute air?
Maximum air throw is measured at the 3rd speed and ranges from 10 m for the HC15-3S model to 24 m for the HC50-3S model. At lower speeds and in the presence of physical obstacles (racking, machinery), the effective air throw is reduced.
To ensure uniform coverage of a 20 m wide hall, the HC20-3S model (19 m air throw) positioned at one end is sufficient; for deeper halls, several units are used in a row. Optimal positioning involves slightly overlapping the air streams from adjacent units to avoid cold spots.
Can the fan speed be adjusted without additional accessories?
The HC-3S series has 3 fixed speeds that can be switched by connecting directly to the motor terminals. Manual switching requires a qualified electrician and changes to the wiring at the electrical panel.
For automatic control, Reventon offers a range of accessories compatible with the HC series: the HC manual room thermostat allows automatic switching between speeds according to room temperature. The HMI programmable thermostat adds weekly programming. The HMI WiFi controller enables remote control via smartphone. Speed control transformers (available from 1.2 A to 14.0 A depending on the model) allow adjustment of the motor power supply. All accessories are available from Krollit.
Which accessories are available for the HC-3S series from Krollit?
Krollit supplies the full range of accessories for the HC series: HC manual room thermostat, HMI programmable thermostat, HMI WiFi controller with touchscreen and smartphone control, speed control transformers (1.2 A / 3 A / 5.0 A / 7.0 A / 14.0 A), 3/4" two-way valve with actuator, 3/4" three-way valve with actuator, swivel mounting bracket (HC20–45 models and HC50–80/Farmer models), 100 cm flexible connectors (pack of 2), drip tray (for HC20–45 and HC50–80 models).
Combining the unit heater with a thermostat and shut-off and balancing valves makes it possible to build a complete system for automatic heating management, with room temperature control and flow modulation according to the required heat load.
Is the HC-3S series suitable for humid environments such as greenhouses or car washes?
The HC-3S series fan has an IP 54 protection rating, allowing it to be used in environments with fine dust and water splashes from any direction. The expanded polypropylene (EPP) housing is not susceptible to corrosion.
In environments with heavy condensation (car washes, rooms with large temperature fluctuations), installing a drip tray (available for HC20–45 and HC50–80 models) beneath the heat exchanger is recommended to collect condensation that forms during start-up transients at low fluid temperatures. Periodic cleaning of the heat exchanger fins is also recommended in rooms where grease or dust is present in the air.
Does Krollit provide technical documentation and support for the HC-3S series?
Krollit, an official Reventon distributor since 2007, provides technical support in Italian and handles accessory and spare part orders from its premises in Monteforte Irpino (AV). Contact: +39 0825-1494022.
Available technical documentation includes: HC-3S data sheet (with performance data for all 8 models), EC declaration and installation instructions. The manufacturer's warranty is 24 months from the date of purchase.
