Heat pump flexoTHERM exclusive VWF 197/4 Controller sensoCOMFORT 720 Internet gateway VR 940f

Product detailed description

Heat pump Vaillant flexoTHERM exclusive VWF 197/4

Vaillant flexoTHERM exclusive VWF 197/4 is the most powerful model in the flexoTHERM exclusive range – a compact, fully indoor-installed ground/water (brine/water) heat pump that can also operate as a water/water pump when using a groundwater source. It is not a classic "split" system with a separate outdoor unit – the entire cooling circuit, compressor and hydraulics are enclosed in a single white cabinet with dimensions 1183 × 595 × 600 mm (height × width × depth), which is installed in the boiler room, technical room or basement. This eliminates the need to worry about the noise of an outdoor unit, frost or long refrigerant pipe runs from the house – only the brine circuit (non-freezing mixture) runs outside to the ground collector or borehole, or two wells in the water/water variant.

The VWF 197/4 model is designed for larger family homes and new builds with higher heat loss, where a heating output of approximately 19.6 kW is required at point B0/W35 (brine temperature 0 °C, hot water output temperature 35 °C, ΔT 5 K according to EN 14511). Thanks to this, it can independently, without a backup electric boiler, cover heating needs even on icy days and simultaneously prepare hot domestic water for a household with multiple bathrooms.

Why a ground/water (brine/water) heat pump

The temperature in the ground at greater depths is stable throughout the year (approx. 8 – 12 °C), so the ground/water heat pump operates with balanced and predictable performance even on the coldest days, unlike air/water pumps, whose performance and efficiency decrease as the outside temperature drops. The result is a higher annual SCOP factor, quieter operation (no outdoor fan) and a longer compressor lifespan, as it does not have to work under extreme temperature differences.

Technical specifications (flexoTHERM exclusive VWF 4th generation range)

• Type: ground/water (brine/water) heat pump, optionally water/water – fully installed indoors
• Heating output at B0/W35: approx. 19.6 kW (model VWF 197/4, most powerful in the range 57 – 197/4)
• Refrigerant: R410A, flow-through closed circuit, factory-filled, no need for compressor testing during installation
• Heating energy class: A+++ at 35 °C / A++ at 55 °C (according to EU regulation 811/2013)
• Cabinet dimensions: 1183 mm (h) × 595 mm (w) × 600 mm (d)
• Weight: approx. 187 kg (empty, without brine filling)
• Control: equithermal controller sensoCOMFORT (VRC 720) included in the package
• Internet connection: gateway VR 940f and myVAILLANT app for remote management
• Acoustic performance: extremely quiet operation thanks to Sound Safe technology (acoustically insulated cabinet, no outdoor unit)
• Minimum installation space: approx. 9 m³ of ventilated technical room (manufacturer's recommendation for the largest models in the range)

sensoCOMFORT 720 controller

The sensoCOMFORT controller (VRC 720 range) is part of the delivery and controls the heating circuit according to the outside temperature, hot water preparation, and optionally a mixing circuit or a second heating circuit in an extended system. The color touch display offers clear time programs for heating and DHW, diagnostics of the heat pump operation, service messages and the ability to control multiple zones. The controller is prepared for communication via the eBUS bus with other Vaillant components (circulation pumps, mixing modules, pool heating, etc.).

Internet gateway VR 940f and myVAILLANT app

The VR 940f module connects the sensoCOMFORT controller to the home WiFi network and thus to the internet. This allows you to monitor and change the temperature, heating and DHW time programs, switch operating modes (economy, vacation, comfort), monitor current consumption and receive a notification in case of a fault even before you notice it yourself via the free myVAILLANT app on your phone or tablet. In the event of a potential fault, the service technician can remotely connect to the system, reducing the time of the visit and waiting for repairs.

Hot water preparation

The VWF 197/4 model is standardly combined with a standing DHW storage heater (e.g. Vaillant uniSTOR or actoSTOR with a volume of 200 – 300 l according to the household's needs), which is heated directly by the heat pump without the need for an electric heating element for most of the year. In the case of higher hot water demand (multiple bathrooms, bathtub, larger family), we recommend a storage tank with a larger volume and possibly also bivalent heating.

Installation and ground heat source

For a model with an output of approx. 19.6 kW, the most common solution is a geothermal borehole (or a pair of boreholes) with a total depth of approx. 150 – 220 m depending on the geology of the site, or a ground collector with sufficient land area (approximately 2 – 2.5 times the heated area of the house). We always recommend having the heat source design (borehole depth, collector length) prepared by a professional design company based on the specific heat loss of the house and geological survey. The installation of the indoor unit is simple – connection to the heating system, DHW and brine circuit, electrical connection and commissioning by an authorized Vaillant service, which is a condition for the warranty validity.

Compatible accessories

• DHW storage heaters Vaillant uniSTOR / actoSTOR in various volumes
• Module VWZ NC for passive cooling via underfloor heating or fancoils (optional accessory, not part of this package)
• Mixing modules for a second heating circuit (e.g. radiator circuit next to underfloor heating)
• Remote room control / room temperature sensor for more precise regulation
• Control modules for photovoltaics (smart grid ready) to use self-produced electricity for pump operation

Why choose flexoTHERM exclusive VWF 197/4

You will appreciate this model especially in larger or less insulated homes, where a standard smaller heat pump cannot cover the peak heat demand on the coldest days. The high output of 19.6 kW allows operation without an electric heating element (monovalent operation) even at design temperatures around -15 °C in our geographical latitudes, which saves operating costs compared to a bivalent solution. The stable temperature of the ground source also ensures high and predictable performance throughout the entire heating season, unlike air-source pumps, whose performance decreases in the cold exactly when you need it most.

Common questions (FAQ)

Do I need an outdoor unit?
No. flexoTHERM exclusive is fully installed indoors, only the brine pipe (non-freezing mixture) runs outside to the ground collector or borehole.

What heat source do I need?
A geothermal borehole, a ground collector, or in the water/water variant a pair of wells (pumping and recharge) with suitable quality groundwater.

Is an electric heater needed?
Usually not if the heat source and heat loss are properly designed to match the 19.6 kW output – the model is designed for monovalent operation even at design winter temperatures.

Can the pump be connected to existing radiators?
Yes, low-temperature radiators or underfloor/stove heating are ideal for higher efficiency, but operation with higher heating water temperature is also possible with sufficient radiator area.

What about service and warranty?
Commissioning must be carried out by an authorized Vaillant service technician, who also confirms the warranty conditions (extended warranty with regular service inspections).

Can passive cooling be added to the pump?
Yes, optionally via the passive cooling module VWZ NC, which uses the cool ground source for gentle summer cooling of the interior via underfloor heating or fancoils (purchased separately).

The technical values mentioned are based on the official Vaillant documentation (installation instructions and technical sheets for flexoTHERM exclusive VWF 57 – 197/4, EU energy label). The exact performance and efficiency in a specific building depend on the heat source sizing, heating system and local climatic conditions – we recommend consulting a designer or authorized Vaillant partner.

Heat Distribution Systems

Heat distribution systems are essential components of any heating system. They ensure that the heat generated by the boiler or heat pump is efficiently distributed throughout the building. There are several types of heat distribution systems, including radiant heating systems, forced-air systems, and hydronic systems.

Figure 1: Schematic representation of a hydronic heating system.

Hydronic systems use water or a water-glycol mixture to transfer heat. The heated fluid is circulated through pipes to radiators, baseboard heaters, or radiant floor systems. These systems are known for their high efficiency and even heat distribution.

• Radiant heating systems: These systems use heated surfaces to emit infrared radiation, which directly heats objects and people in the room.
• Forced-air systems: These systems use a furnace to heat air, which is then distributed through ducts by a blower fan.
• Hydronic systems: These systems use water as the heat transfer medium and are often used in combination with radiant floor heating.

Each type of heat distribution system has its advantages and disadvantages. The choice of system depends on factors such as building design, energy efficiency requirements, and budget constraints.

Figure 2: Comparison of radiant, forced-air, and hydronic heating systems.

When selecting a heat distribution system, it is important to consider the thermal performance, maintenance requirements, and compatibility with other components of the heating system. Proper installation and regular maintenance are crucial for ensuring optimal system performance and longevity.