Vaillant aguaFLOW exclusive VPM 40/45/2 W - hot water preparation module

Product detailed description

Vaillant aguaFLOW exclusive VPM 40/45/2 W – a more powerful module for hygienic domestic hot water preparation

The Vaillant aguaFLOW exclusive VPM 40/45/2 W (manufacturer's order number 0010015138) is the most powerful member of the aguaFLOW exclusive family of fresh water stations designed for flow-through (hygienic) preparation of domestic hot water in combination with a heating water buffer cylinder. Where the smaller VPM 30/35/2 W model is sufficient for an ordinary family house, this more powerful variant is intended primarily for larger family houses with multiple bathrooms, apartment buildings, guesthouses, small businesses with shared showers, or buildings with simultaneous hot water draw-off from several points at once. Thanks to the higher output of the heat exchanger and a stronger circulation pump, the module can maintain a stable hot water temperature even under significant and variable draw-off, which is typical for multi-storey residential buildings.

Just like its smaller sibling, this is a device without any stored volume of drinking water inside – hot water is generated exclusively at the moment of draw-off, passing through a stainless steel plate heat exchanger, where heat from the heating water buffer tank is transferred to the drinking water side without direct contact between the two media. This concept eliminates the risk of legionella bacteria growth, which is associated with the long-term storage of a larger volume of lukewarm water in classic storage water heaters.

Performance parameters and operating principle

The designation "40/45" indicates the output in litres per minute: at a set outlet temperature of 60 °C, the module delivers a continuous flow of approximately 40 l/min, and at 65 °C approximately 45 l/min. This corresponds to the simultaneous filling of approximately two to three shower stalls or one larger bathtub together with a kitchen sink without a noticeable drop in temperature or pressure. An integrated highly sensitive flow sensor together with fast electronic control ensures that even in the event of a sudden change in draw-off (for example, when a second shower is turned on at the same time), the temperature adjusts and stabilizes instantly without unpleasant temperature fluctuations.

The adjustable outlet temperature range is 40–75 °C, and the module also features a periodic thermal disinfection function at approx. 70 °C as additional protection for the hot water distribution system. The control electronics communicate via the eBUS bus with the heat source and the Vaillant system controller, so the entire system (boiler/heat pump + buffer cylinder + aguaFLOW module) functions as a single logical unit with unified control and diagnostics from one place.

Electrical section and pump output

Due to the higher hydraulic output, the VPM 40/45/2 W module is equipped with a more powerful, high-efficiency circulation pump with a max. power input of approximately 227 W (compared to approx. 87 W for the smaller VPM 30/35/2 W model), which corresponds to the higher heating water flow rate needed to achieve the declared output. Despite the higher power input, this is a high-efficiency class pump that automatically adapts to the current operating demand and does not run unnecessarily at full power when no hot water is being drawn off.

Installation, connection and space requirements

Just like the smaller model, the VPM 40/45/2 W can be installed in two ways – directly onto the buffer cylinder (typically the allSTOR exclusive range) using a quick-connect coupling system, or separately on a wall with connection to the cylinder via heating pipework, which is used especially during boiler room modernizations or where the spatial layout does not allow direct installation. Connection dimensions remain the same as for other models in the range – G 1" for the heating supply and return, G 3/4" for hot and cold water including any circulation.

Cascade connection for larger buildings

For buildings with even higher requirements for simultaneous draw-off (for example, multi-storey apartment buildings, dormitories, larger businesses), up to four aguaFLOW exclusive modules can be connected into a shared cascade. The system automatically distributes the load among the individual units and, if needed, gradually connects additional modules to always ensure sufficient output without unnecessary wear on unused stations. Each additional module in the cascade (except the first, so-called master module) requires a separate cascade electric valve, which is available as a separate accessory and ensures correct hydraulic switching between the individual modules.

Technical characteristics

Compatible components and recommended setup

The VPM 40/45/2 W module is designed primarily to work together with allSTOR exclusive range buffer cylinders and Vaillant heat sources – ecoTEC plus/pro/exclusiv condensing boilers, ecoCRAFT cascade boilers, aroTHERM heat pumps, or in combination with the auroFLOW solar module in systems with solar-assisted hot water preparation. The system controller (e.g. sensoCOMFORT 720 or multiMATIC 700) then unifies control of the entire setup via the eBUS bus, including heating time programs and comfort/economy mode settings.

Benefits for the building operator

• Higher comfort during simultaneous draw-off – suitable where multiple bathrooms or showers are used at the same time.
• Reduced operating costs – compared to keeping a large volume of hot water stored in a cylinder, only the actually drawn-off amount is heated.
• Higher hygienic safety – minimized risk of legionella thanks to the absence of stored hot water in the module.
• Modular scalability – possibility of additional expansion with further modules in a cascade as the building's requirements grow.
• Simple integration – full communication with the existing Vaillant system via eBUS without the need for separate higher-level control.

Installation recommendations

Given the module's higher output, when designing the system it is important to correctly size the heat source and buffer cylinder so that a sufficiently high temperature and volume of heating water is available in the upper layer of the cylinder, corresponding to the planned simultaneous hot water draw-off. Installation, commissioning, and parameter setting (target temperature, disinfection cycle, possible inclusion in a cascade) must be carried out by a qualified technician trained for Vaillant products. It is also recommended to assess the quality of the incoming water and, in the case of increased hardness, consider installing water treatment ahead of the module, which will extend the service life of the plate heat exchanger.

Maintenance

As part of the regular annual service inspection, the following are checked in particular for this module:

• condition and efficiency of the plate heat exchanger (the risk of limescale deposits is somewhat more pronounced at higher flow rates),
• functionality of the flow sensor and speed of the control response,
• tightness of hydraulic connections on both the heating and drinking water sides,
• operation and noise level of the circulation pump,
• correctness of the thermal disinfection settings and cycle.

In the event of a drop in output, the most common cause is limescale build-up in the heat exchanger, which is removed by professional chemical flushing without the need to replace the entire unit.

Why choose the high-output VPM 40/45/2 W model

Where simultaneous hot water draw-off from multiple points is expected – a larger family with several bathrooms, an apartment building, a small business with several showers – the more powerful aguaFLOW exclusive VPM 40/45/2 W module represents an investment that ensures stable comfort without compromise. A higher output also means a greater reserve for the future, if the demand for hot water in the building increases over time, for example due to an extension or a change in the way the building is used.

Frequently Asked Questions

Module commissioning procedure – step by step

Correct commissioning of the VPM 40/45/2 W module is essential for achieving the declared output and reliable long-term operation. A service technician typically follows this procedure:

1. Checking the hydraulic connection – verifying the correct connection of the heating water supply and return (G 1") as well as the drinking water side (G 3/4"), including flow direction and tightness of all connections.
2. Filling and venting the system – filling both the primary (heating) and secondary (drinking water) sides of the module, thoroughly venting the heat exchanger and pump to prevent noisy operation or reduced output.
3. Electrical connection and communication – connecting the 230 V power supply and linking the module via the eBUS bus with the heat source and system controller.
4. Parameter configuration – setting the target hot water temperature, thermal disinfection temperature, and, if applicable, cascade parameters if the module is part of one.
5. Functional test – simulating various levels of hot water draw-off and verifying that the module maintains a stable temperature across the entire declared output range.
6. Handover to the user – training on basic operation, explanation of the values shown on the display, and handover of the equipment documentation.

Typical design and installation mistakes and how to avoid them

When designing and installing larger systems with the VPM 40/45/2 W module, several mistakes occur repeatedly, which are worth avoiding in advance:

• Undersized buffer cylinder – if the cylinder cannot provide sufficient volume and temperature of heating water in the upper layer, the module will not achieve its declared output regardless of its own technical parameters.
• Insufficiently sized heat source – with frequent simultaneous hot water draw-off from multiple points, the heat source (boiler, heat pump) must be able to reheat the buffer cylinder quickly enough, otherwise the temperature in the cylinder will gradually drop, and consequently so will the module's output.
• Missing water treatment for harder water – without adequate water treatment, limescale builds up faster in the heat exchanger, reducing output over time.
• Underestimating the sizing of the circulation circuit – for buildings with longer distribution pipes, it is advisable to plan from the start for one of the available hot water circulation sets, so that the solution does not need to be added later in a complicated way.

Operating economics

Although the purchase price of the high-output VPM 40/45/2 W module is higher than that of a classic storage water heater of comparable output, in operation it brings savings by heating only the actually drawn-off amount of water, without the heat losses associated with keeping a large volume of hot water at a high temperature in a cylinder for a long time. For buildings with variable or intermittent draw-off (typically apartment buildings with multiple households), this saving can be significant over the service life of the equipment, especially in combination with a correctly sized heat source and possible solar support.

Summary

The Vaillant aguaFLOW exclusive VPM 40/45/2 W is the most powerful module in the aguaFLOW exclusive family, designed for buildings with higher demands for simultaneous hot water draw-off. Together with a suitable buffer cylinder and Vaillant heat source, it provides hygienically safe, comfortable, and energy-efficient hot water preparation with the option of further expansion via a cascade.