Vaillant high-efficiency class A electronic pump for ecoCRAFT 120/160 kW

Product detailed description

High-efficiency electronic class A pump for Vaillant ecoCRAFT 120/160 kW

This high-efficiency electronic class A boiler circuit pump is a genuine Vaillant accessory intended for floor-standing condensing boilers of the ecoCRAFT series with 120 kW and 160 kW output (for example the models ecoCRAFT exclusiv VKK 1206/3-E and VKK 1606/3-E). This is the mid-power segment of the ecoCRAFT series, which covers an output range of roughly 80 to 280 kW divided into six power stages, with boiler body dimensions of approximately 1285 × 695 × 1240 mm (H × W × D) for these two models. This segment is typically installed in boiler rooms of larger apartment buildings, administrative buildings and industrial facilities, where higher capacity than the basic 80 kW model is required, but the highest power stages of the series are not yet necessary.

The pump ensures forced circulation of heating water through the boiler's primary heat exchanger and its further distribution into the system. It is an electronically commutated type with continuous speed control, which changes directly according to the current burner modulation (ecoCRAFT boilers operate with a modulation range of roughly 17% to 100% of nominal output) – at a lower current boiler output, the pump automatically reduces its speed and thus electricity consumption, while at full output it ensures sufficient flow for the safe removal of heat produced from the exchanger.

Technical characteristics

• Intended for: Vaillant ecoCRAFT (VKK) with 120 kW and 160 kW output
• Pump type: high-efficiency electronically controlled boiler circuit circulation pump, energy efficiency class A
• Control: continuous speed change according to the current burner modulation of the boiler (modulation range roughly 17 – 100%)
• Housing material: durable cast iron, circulation section (rotor, bearings) adapted to standard parameters of treated heating water
• Electrical connection: directly from the boiler's control board, without the need for a separate external power source or external speed control
• Max. operating water temperature: up to 110 °C
• Max. system operating pressure: up to 6 bar
• Noise level: low, electronically commutated motor without mechanical brushes
• Installation: directly onto the ecoCRAFT 120/160 kW boiler body, according to the manufacturer's installation manual

Why this pump is essential for ecoCRAFT 120/160 kW boilers

In this mid-power segment of the ecoCRAFT series, the volume of water flow and the demands on pump head are significantly higher than for the basic 80 kW model, which is why Vaillant developed a separate design variant of the pump with a higher flow cross-section for this segment. Boilers of this output are, in practice, installed either as a standalone heat source for a larger building, or in a cascade arrangement of multiple units, where it is essential to guarantee precisely defined and even flow through each individual boiler body. Insufficient flow at a given output leads to an increased temperature difference between flow and return (ΔT), which increases thermal stress on the exchanger and may trigger a protective boiler shutdown, unnecessarily limiting the available output of the system precisely at the moment of greatest heat demand.

The electronic integration with the boiler's control unit, which adjusts the pump speed directly according to the current burner modulation, is also the reason why it is recommended to use exclusively a genuine Vaillant pump matching the given power stage for this type of boiler – both the communication protocol and the control curve are set by the manufacturer specifically for this particular component.

Installation and hydraulic connection

Installation must be carried out exclusively by an authorized service technician with professional qualification for the installation of gas and heating equipment, in accordance with the manufacturer's installation manual. The pump is mounted directly onto the ecoCRAFT 120 or 160 kW boiler body, followed by venting of the circuit and a tightness check at operating pressure. In a cascade arrangement of multiple boilers, the pump of each boiler is set up and tested individually, after which the entire cascade is tested as a functional whole, including hydraulic balancing of the individual branches.

We recommend that the same service order also include a check of the heating water quality according to the VDI 2035 guideline, since improperly treated water significantly shortens the service life of the circulation pump and the boiler's primary exchanger, regardless of the quality of the component itself. In practice, this pump is most often installed during the initial installation of a new ecoCRAFT boiler of this output, when replacing a faulty or worn-out pump, or when expanding an existing boiler room with an additional boiler into a cascade arrangement.

Compatibility

The pump is intended exclusively for Vaillant ecoCRAFT floor-standing condensing boilers with 120 kW and 160 kW output (for example models designated VKK 1206/3-E and VKK 1606/3-E from the ecoCRAFT exclusiv series). The ecoCRAFT series covers an output range of roughly 80 to 280 kW in six power stages, with Vaillant supplying a separately dimensioned pump with different flow parameters for each segment (80 kW; 120/160 kW; 200/240/280 kW). This component is therefore not interchangeable with pumps intended for the lower (80 kW) or higher (200/240/280 kW) power segments, nor with pumps for other Vaillant boiler series. When ordering, we recommend always verifying the exact power designation of the boiler, for example directly on the rating plate.

This caution is especially worthwhile for service work carried out by a company other than the one that originally installed the boiler, since without knowledge of the exact order history, the boiler's rating plate is the only reliable source of information.

Maintenance and care

High-efficiency electronic pumps of this type practically require no manual maintenance during normal operation – they have no lubrication points or mechanical components requiring regular lubrication. As part of the annual boiler service inspection, we recommend checking:

• the tightness of the pump connection to the boiler body,
• the noise level and smoothness of pump operation,
• the functionality of the electronic speed control compared to the required boiler modulation,
• the quality of the heating water and any deposits in the circulation section during professional disassembly during service.

In cascade arrangements, where some boilers may be temporarily out of operation, we recommend verifying that the control unit regularly alternates the load between the individual boilers of the cascade, thereby preventing one pump from standing idle for a long time and the risk of jamming due to deposits.

This load rotation evenly extends the service life of all pumps in the cascade and reduces the risk of one particular pump being overloaded long-term while the others remain mostly idle.

Why choose a genuine Vaillant component

A genuine pump guarantees precise hydraulic and electronic matching with the ecoCRAFT boiler's control unit, which directly affects the reliability and service life of the entire installation at this power level. The component undergoes the same quality control as the boiler itself, and its use is also a condition for recognition of the manufacturer's warranty on the boiler body in the event of a fault related to the circulation of heating water. Given the high value of the investment in a boiler of this power segment, the use of a non-genuine or incorrectly dimensioned pump is clearly not recommended, as a fault caused by an incorrect component could lead to significantly higher costs than the price difference compared to a genuine accessory.

About the Vaillant ecoCRAFT series and the place of the 120/160 kW segment

ecoCRAFT exclusiv (VKK) is a proven series of floor-standing gas condensing boilers by Vaillant intended for commercial, industrial and larger residential applications, with an output range of roughly 80 to 280 kW divided into six power stages. The 120/160 kW segment represents the mid-range category of this series, suitable for example for boiler rooms of medium-sized apartment buildings or administrative buildings, where the standalone 80 kW model is no longer sufficient, but the highest capacity of 200 – 280 kW is not yet necessary. This mid-range position makes the 120/160 kW segment one of the most frequently chosen power stages when designing new medium-sized boiler rooms. Boilers of this series achieve high rated efficiency even at partial load and operate with continuous burner output modulation over a wide range, which, combined with a correctly dimensioned electronic pump, allows efficient operation with fluctuating heat demand throughout the day and year.

Vaillant supplies three separately dimensioned variants of this pump for the ecoCRAFT series according to the boiler's power segment – for 80 kW, for 120/160 kW (this component) and for 200/240/280 kW. This differentiation ensures that in each power segment, the pump operates at the optimal operating point in terms of both flow and electricity consumption. When ordering a cascade arrangement combining boilers of different power stages, it is therefore necessary to order a pump matching the specific power segment for each boiler, not a single universal component for the entire cascade, since mixing up segments could lead either to insufficient flow or to unnecessarily high electricity consumption.