Vaillant aroVAIR VA 2-035 CN – console fan coil unit 3.5 kW (cooling/heating)

Product detailed description

Vaillant aroVAIR VA 2-035 CN (order code 0010035092) is a mid-power console fan coil unit from the aroVAIR VA 2 CN series, reaching a cooling and heating capacity of 3.50 kW at the highest fan speed. It is the typical "workhorse" of the whole series – powerful enough for a standard living room, medium-sized bedroom, or office, yet still compact and quiet enough not to disturb everyday household life. Like the other models in the range, it works with water from an air-to-water heat pump (typically a Vaillant aroTHERM) instead of its own refrigerant circuit.

How the two-pipe fan coil unit works

The VA 2-035 CN fan coil unit has no compressor or outdoor unit of its own – it receives heat or cold via water circulating through its three-row copper heat exchanger with aluminium fins. A built-in direct current (DC/EC) fan, this time made up of two separate rotors due to the longer casing of the unit, forces air from the room to flow through this heat exchanger and returns it to the space already cooled or heated. Because it is a two-pipe design, the same circuit and the same heat exchanger are used in winter for supplementary heating with hot water and in summer for cooling with cold water – switching between modes is handled either directly by the heat source (heat pump) or by an optional 3-way switching valve kit fitted on the branch to the unit.

The advantage of this principle over a classic split air conditioning system is that there is no need to run refrigerant piping through the facade or install a separate outdoor unit – a connection to the existing water piping from the heat pump, which the house likely already has installed for heating, is enough. In practice this means lower installation costs both in renovations and new builds where an air-to-water heat pump is the main heat source.

Technical parameters of the VA 2-035 CN

The values come from the official technical data sheet of the manufacturer Vaillant for the aroVAIR VA 2 CN series and are measured according to EN 1397 under test conditions: cooling – water 7 °C/12 °C (inlet/outlet), room air 27 °C dry bulb/19 °C wet bulb; heating – water 45 °C at ΔT 5 K, room air 20 °C.

• Cooling capacity (total): 2.22 kW (low speed) / 2.89 kW (medium) / 3.50 kW (high)
• Sensible / latent cooling capacity (high speed): 2.65 kW sensible / 0.85 kW latent
• Heating capacity (total): 2.19 kW / 2.87 kW / 3.50 kW
• Water flow rate – cooling: 400 l/h / 510 l/h / 610 l/h
• Water flow rate – heating: 430 l/h / 560 l/h / 680 l/h
• Pressure drop – cooling: 14.82 kPa / 24.41 kPa / 35.1 kPa
• Pressure drop – heating: 14.82 kPa / 24.41 kPa / 35.1 kPa
• Air flow rate: 340 m³/h (low) / 470 m³/h (medium) / 595 m³/h (high)
• Fan power input: 10 W / 17 W / 26 W
• Rated current: 0.18 A
• Sound pressure level: 25 dB(A) / 32 dB(A) / 38 dB(A)
• Sound power level: 37 dB(A) / 45 dB(A) / 52 dB(A)
• Power supply: 220–240 V, 1 phase, 50 Hz
• Fan type and number: direct current (DC) motor, forward-curved centrifugal fans, 2 pcs
• Heat exchanger: 3 tube rows, tube diameter 7.94 mm, max. working pressure 1.6 MPa
• Hydraulic connection inlet/outlet: G 3/4"
• Condensate outlet outer diameter: 18.5 mm
• Dimensions (W × H × D): 1240 × 495 × 200 mm
• Net weight: 25.5 kg
• Installation type: console (wall-mounted), optionally ceiling-mounted
• Room operating temperature range: 17–30 °C, cooling and heating

What spaces the VA 2-035 CN is suitable for

With a capacity of 3.50 kW, this model covers a standard living room, larger bedroom, open kitchen with dining area, or office room with a floor area of roughly 25 to 35 m² – the exact range always depends on the building's heat loss/load, orientation to the cardinal points, window glazing, and ceiling height. In apartment buildings and family houses with an air-to-water heat pump, this power class is the one most often chosen for the main living rooms, while the smaller VA 2-015 CN is sufficient for small rooms and the VA 2-045 CN or VA 2-070 CN is used for large open spaces.

Thanks to the two fans in a single casing, the unit runs more smoothly even at higher speeds compared with single-fan models – this is especially appreciated when quickly cooling a room down after coming home on a hot summer day, when it is a good idea to temporarily switch to a higher speed setting.

Installation and hydraulic connection

The VA 2-035 CN is most often installed as a console (wall-mounted) unit under a window, or alternatively against a wall on separate VAZ-015-070-F1 legs (free-standing installation directly on the floor), or ceiling-mounted if the layout of the room requires it. In all mounting variants, minimum clearances must be maintained around the air intake and outlet grille so as not to restrict the declared air flow rate and, with it, the unit's capacity.

The hydraulic connection to the supply and return branch with a G3/4" internal thread should be fitted with shut-off valves in case of future maintenance or heat exchanger replacement without having to drain the entire heating/cooling circuit. In cooling mode, condensate will form on the heat exchanger – the unit has its own collection tray with an outlet of 18.5 mm outer diameter, which must be connected to a sloped drain to the sewer system or a collection vessel, otherwise there is a risk of overflow and damage to surrounding surfaces from moisture.

The 230 V electrical connection requires a separate protected circuit in accordance with applicable standards; control itself (mode selection, fan speed, and desired temperature) is handled by a room controller wired to the unit's terminal block – without it, the fan coil unit cannot be operated to its full extent. For a two-pipe system with shared heating/cooling switching at the source level, we also recommend adding a 3-way switching valve kit for the 1.5 to 4.5 kW power range, which is suitable for this specific model.

Recommended accessories

• VA 1-WC DC – analogue dial controller, Heating/Cooling/OFF modes, 3 fan speeds (MIN/MED/MAX) – simple and reliable operation.
• VA 2-WC C – electronic controller with 7 fan speeds and Auto/Heating/Dehumidifying/Cooling modes – finer comfort control.
• VA 2-WC D – digital controller with display, automatic mode, and Auto/Heating/Dehumidifying/Cooling/Fan operating modes – the highest level of operating comfort.
• 3-way switching valve kit (1.5–4.5 kW) – for a two-pipe connection with alternating switching between heating and cooling.
• VAZ-015-070-F1 legs – for free-standing (floor) installation instead of wall or ceiling mounting.

Maintaining the VA 2-035 CN fan coil unit

Regular, simple maintenance keeps the declared capacity and quiet operation of the unit throughout its service life:

• Air filter – inspect and clean according to the dustiness of the environment, ideally before the start of both the heating and cooling season, and more often in households with pets or allergy sufferers.
• Condensate drainage – before summer operation, check that the drain is clear; a clogged tray or hose can cause condensate to overflow into the interior.
• Bleeding the heat exchanger – after installation and after any intervention in the piping, check for air in the circuit, which reduces capacity and causes noisy water flow.
• Heat exchanger fins – clean with a soft brush or a low-power vacuum cleaner, avoiding mechanical damage to the delicate aluminium fins.
• Mounting check – for free-standing installation on legs, check the stability and tightness of joints once a year.

Why choose the VA 2-035 CN

If an air-to-water heat pump in your home already provides heating and hot water preparation, the VA 2-035 CN is the most universal addition for actively cooling the main living spaces without the need to invest in a separate split air conditioning system. Its capacity of 3.50 kW covers most typical rooms in a family house or apartment, and thanks to a unified system from a single manufacturer (Vaillant), compatible controls and easier servicing in the future are guaranteed.

Where the VA 2-035 CN fits within the aroVAIR VA 2 CN range

The Vaillant aroVAIR VA 2 CN range of console fan coil units has four power levels built on the same technical platform – two-pipe design, three-row heat exchanger, direct current (DC) fan with three speed settings, and the same G3/4" hydraulic connection:

• VA 2-015 CN – 1.50/1.57 kW, 1 fan, dimensions 790 × 495 × 200 mm, 18 kg – small rooms up to approx. 15–18 m².
• VA 2-035 CN (this product) – 3.50/3.50 kW, 2 fans, dimensions 1240 × 495 × 200 mm, 25.5 kg – standard living room or bedroom, 25–35 m².
• VA 2-045 CN – 4.30/4.30 kW, 2 fans, dimensions 1240 × 495 × 200 mm, 25.5 kg – same casing as the VA 2-035 CN, but a more powerful heat exchanger for more demanding spaces.
• VA 2-070/075 CN – 7.35/8.05 kW, 3 fans, dimensions 1360 × 591 × 200 mm, 32.5 kg – large open spaces or commercial applications.

Interestingly, the VA 2-035 CN and VA 2-045 CN share exactly the same outer casing dimensions (1240 × 495 × 200 mm) – the difference between them lies purely in heat exchanger performance and flow parameters, so in terms of installation space requirements the two models are interchangeable, and the choice between them should be based solely on a thermal calculation of the room.

Pipework insulation and real-world operating efficiency

For the VA 2-035 CN to achieve its rated capacity values, it is essential to ensure a sufficient water flow rate through the heat exchanger (400 to 610 l/h depending on the selected speed) – meaning a correctly sized circulation pump and piping in the heat pump circuit. Equally important is high-quality thermal insulation on all supply and return pipework leading to the unit, particularly in cooling mode, when the surface temperature of the pipe drops below the dew point of the surrounding air and, without insulation, condensation would form and damage building structures through moisture.

In terms of operating costs, this is a more economical solution than a separate split air conditioning system – the fan coil unit does not drive its own compressor, only a fan with a power input of 10 to 26 W depending on the selected speed, while the main share of the energy needed to produce cooling or heating is in any case consumed by the heat pump, which runs in the house for heating and hot water preparation regardless of whether a fan coil unit is connected to it or not.

Frequently asked questions