Vaillant aroVAIR VA 2-WC C – electronic controller for console fan coils

Product detailed description

Vaillant aroVAIR VA 2-WC C – electronic controller for console fan coils

Vaillant aroVAIR VA 2-WC C (order number 0010035096) is an electronic room controller designed to operate console (windowsill-type) fan coils from the Vaillant aroVAIR VA 2 CN series – i.e. units VA 2-015 CN, VA 2-035 CN, VA 2-045 CN and VA 2-070(075) CN. These two-pipe fan coil units are most commonly connected to a Vaillant aroTHERM air-to-water heat pump (or another source of hot or cold water in the system) and are used for supplementary heating during transitional seasons and, above all, for active cooling of the interior in summer. The VA 2-WC C controller is the heart of the entire system – without it, the fan coil does not know when to run, at what speed, or in which mode.

This is an electronic (not purely analogue) version of the controller with its own temperature display, positioned in the aroVAIR accessory range between the simple analogue dial controller VA 1-WC DC and the full-featured digital controller with automatic mode switching VA 2-WC D. The VA 2-WC C offers 7 fan speed levels (instead of just 3 levels – MIN/MED/MAX – on the analogue version), selectable operating modes Auto / Heating / Dry / Cooling, and a continuously adjustable target room temperature – meaning significantly finer and more comfortable control than the basic analogue controller, but at a lower price than the fully digital model with automatic mode switching.

The controller is designed as a universal accessory for the entire VA 2 CN power range – the same unit can be used with a small unit for a bathroom or bedroom (VA 2-015 CN) as well as with a large unit for a living room or open-plan space (VA 2-070 CN). This means the investor doesn't have to worry about choosing the "correct" controller variant according to the fan coil's output.

Technical parameters

• Device type: electronic wall-mounted / built-in controller (wired connection to the fan coil)
• Dimensions (H × W × D): approx. 105 × 75 × 15 mm
• Installation method: on the wall (standalone control panel) or integrated directly into the console unit's casing
• Temperature measuring range (room sensor): −15 °C to 43 °C
• Adjustable target temperature range: 17 °C to 30 °C
• Max. contact switching voltage: 220 V
• Number of switching/relay stages: 3 (control of fan speed levels and the valve)
• Fan speed levels: 7 levels or automatic mode based on deviation from the target temperature
• Operating modes: Auto, Heating, Dry, Cooling
• Display: yes, shows current/set temperature
• Backlight: can be turned on/off
• Power supply: low voltage from the fan coil's control electronics (no separate power adapter required)
• Compatibility: Vaillant aroVAIR VA 2-015 CN, VA 2-035 CN, VA 2-045 CN, VA 2-070/075 CN
• Recommended accessories for two-pipe (2-pipe) systems: 3-way switching valve set VA 2-3VW C (up to 4.5 kW) or VA 2-3VW 070C (7 kW)
• Country of origin: Germany / EU (manufactured within the Vaillant Group)
• Warranty: 2 years

How the VA 2-WC C works in practice

The controller measures the air temperature at the installation location (either directly inside the wall-mounted controller body, or via an integrated sensor if built into the unit's casing) and, based on the difference between the measured and target temperature, controls the fan coil's fan speed across 7 levels. In Auto mode, the system automatically decides whether the unit should heat or cool depending on the water currently flowing into the heat exchanger (in a two-pipe system, in cooperation with the 3-way valve set, which switches between the heating and cooling circuits at the source level). Dry mode is designed for dehumidifying the air during transitional months, when full cooling output isn't needed – just a reduction in humidity – the fan runs at low speed and the heat exchanger operates with cold water only enough to condense moisture out of the air.

The display continuously shows the current room temperature and allows easy setting of the target value within the 17 – 30 °C range. The display backlight can be switched off, which is particularly useful when installed in a bedroom, where a permanently lit control panel could be disruptive during sleep.

Installation and wiring

The VA 2-WC C connects to the fan coil's control board via a low-voltage multi-core cable (typically routed inside the wall or in a cable duct together with the rest of the unit's wiring). There are two common installation variants:

• Standalone wall controller – the controller is mounted on the wall at a location suitable for measuring a representative room temperature (not directly above a radiator, away from direct sunlight, away from drafts from doors and windows, at a height of approximately 1.2 – 1.5 m above the floor).
• Integration directly into the fan coil casing – if a separate wall-mounted location is not required (e.g. for units installed in a visible location in the room where controlling the unit directly on its panel is sufficient), the controller can be built into the console body.

Electrical wiring (connection to the fan coil's PCB, or to the additional 3-way valve in a two-pipe system) must be carried out by a qualified technician authorised to install heating/cooling equipment, in accordance with the Vaillant installation manual for the given type of VA 2 CN unit. Before first switch-on, the correct connection of terminals must be checked against the wiring diagram supplied with the fan coil, and the controller's address/configuration set if required by the type of installation (e.g. with multiple units in one zone).

When to choose the VA 2-WC C

When selecting a controller for an aroVAIR console fan coil, atria.sk offers three levels of control:

• VA 1-WC DC – the simplest analogue dial controller with 3 fan speed levels (MIN/MED/MAX) and basic Heating/Cooling/Off modes, without a display.
• VA 2-WC C – this model: an electronic controller with a display, 7 fan speed levels and Auto/Heating/Dry/Cooling modes – a suitable compromise between price and comfort.
• VA 2-WC D – the most comfortable digital controller with full automatic mode switching based on the return water temperature.

The VA 2-WC C is therefore an ideal choice for homes and offices where the user wants to fine-tune the fan speed more precisely (e.g. due to noise levels in a bedroom at night) and make use of a dedicated dehumidification mode, but does not need fully automatic heating/cooling switching without manual intervention.

Maintenance and care

The VA 2-WC C controller requires almost no maintenance – it is an electronic device with no moving mechanical parts prone to wear. It is recommended to:

• Clean the surface and display with a dry, soft cloth (without chemical cleaning agents or solvents, which could damage the plastic housing or button labels).
• Avoid exposing the controller to direct water splashing or excessive humidity – although the fan coil itself is designed for damper conditions (condensation during cooling), the electronic controller itself belongs in a dry environment away from dripping water.
• Regularly (at least once a season) check that the mode settings correspond to the time of year – especially when transitioning from the heating to the cooling season, it is recommended to verify the function of the 3-way switching valve, if part of the installation.
• In case of a fault or unusual behaviour (e.g. the unit does not respond to setting changes), first check the power supply and the connecting cable to the fan coil, or contact a Vaillant service technician.

Why buy from us

We offer the Vaillant aroVAIR VA 2-WC C as an original accessory, directly compatible with the entire range of Vaillant aroVAIR VA 2 CN console fan coils. The product is supplied with a 2-year warranty and advice on choosing the right combination of fan coil + controller + optional 3-way valve for your specific type of installation (single-pipe vs. two-pipe system). If you are not sure which controller is right for your installation, we will be happy to advise you before ordering, based on the type of your heat pump and the method of hydraulic connection.

Why choose a fan coil over a classic split air conditioner

Customers who already have, or are planning to install, a Vaillant aroTHERM air-to-water heat pump often ask whether it is better to add a classic split air conditioner or a water fan coil such as the aroVAIR VA 2 CN controlled by the VA 2-WC C. The difference is fundamental: a split air conditioner needs its own refrigerant circuit, a compressor in the outdoor unit, and copper piping for refrigerant distribution – meaning an additional outdoor compressor, an additional electrical connection, and servicing by a refrigeration specialist. A fan coil, on the other hand, uses the water that already circulates in the home's heating/cooling system thanks to the existing heat pump. It is therefore enough to bring two pipes (flow and return) to the unit, connect the condensate drain, and install the VA 2-WC C controller – without needing additional refrigerant, another outdoor unit, or any intervention in the roof or façade structure for a new compressor.

This concept is particularly advantageous for new builds and renovations where the heat pump is part of the project from the start – a single heat/cold source can then serve underfloor heating, radiators and fan coils simultaneously, reducing the number of devices that need to be serviced and maintained.

Energy efficiency and operating costs

The VA 2-WC C controller contributes to the efficient operation of the fan coil by allowing fine adjustment of fan output in 7 steps instead of coarse switching between just a few speeds. This means the unit doesn't need to run needlessly at full output when a lower speed is sufficient to maintain the target temperature – this reduces the electricity consumption of the fan itself (a fan coil does have higher air-circulation power consumption compared to a classic radiator or convector, since it requires an electrically driven fan, but this consumption is minimal with the modern EC/DC motors used in aroVAIR fan coils, compared to the output the unit delivers to the room in the form of heat or cold).

The Auto mode also continuously monitors the deviation from the set temperature and smoothly adjusts the fan speed – in practice, this means quieter operation for most of the day (the unit runs at lower speeds when the room temperature is close to the target value) and higher output only at moments of greater deviation, for example after coming home to a cold or overheated apartment.

Typical installation mistakes and how to avoid them

The following shortcomings are most commonly encountered in practice when installing VA-WC series controllers:

• Sensor placed in an unsuitable location – mounting above a radiator, in a corner behind furniture, or on a wall exposed to direct sunlight distorts the measured temperature and causes the unit to fail to deliver the expected comfort. The controller should measure the temperature at a representative location in the room, away from heat sources and drafts.
• Swapped terminals during wiring – incorrect wiring between the controller and the fan coil board can cause the unit to fail to respond to mode changes or to run continuously at one speed. Always follow exactly the wiring diagram supplied with the given VA 2 CN type.
• Omitting the 3-way valve in a two-pipe system – if the installation is two-pipe (alternating hot/cold water in the same pipe), switching between heating and cooling cannot be automatically controlled without the 3-way valve set, and there is a risk of modes being incorrectly mixed.
• Underestimating the cable reach when choosing the installation location – before drilling into the wall, it is advisable to check the available length of the connecting cable between the controller and the unit, to avoid needing to extend the wiring afterwards.

Frequently Asked Questions