REX EC V2 - heat recovery controller, recuboxes and heat...
regulation for a system with EC fans, frost protection or BY-PASS control programming of ventilation intensity, monitoring filter replacement, quick ventilation - control from the toilet,
We offer a wide range of enthalpy heat exchangers for most heat recovery ventilation units.
If you can't find the right model, contact us – we'll be happy to help!
The foundation for high-tech heat recovery.
RECUBOX® HRV 250 VENT-READY TOP is ready for easy installation of.
High-performance AFL EC fans with the CONSTANT FLOW system.
RECUBOX® HRV 250 VENT-READY TOP is a compact non-enthalpy heat recovery unit ready for installation of AFL CONSTANT FLOW EC fans. The TOP version, with all four connection ports facing upwards, saves space and simplifies connection to the ventilation ductwork above the unit. RECUBOX® provides an exceptionally durable, hygienic and versatile foundation for modern balanced heat recovery ventilation in family houses, apartments and smaller commercial buildings.
Custom-made in the Czech Republic. RECUBOX® units are manufactured entirely in the Czech Republic according to the customer's exact requirements. We use high-quality polypropylene materials from SIMONA AG and professional hot-gas welding technology using equipment from Leister AG.
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Every RECUBOX® is made as a thoroughly engineered technical product – with an emphasis on precision, airtightness, long service life and the possibility of adapting it to a specific installation.
Product image notice: The photographs are illustrative and may not show the exact variant or selected RECUBOX® configuration being offered. The relevant technical drawings and diagrams are decisive for the specific version, dimensions and positioning of individual structural components.
The casing is structurally optimised for installation of AFL EC CONSTANT FLOW fans, which represent an exceptionally smart solution for modern heat recovery ventilation. Thanks to the integrated Constant Flow function, the fans automatically respond to changes in system resistance and help maintain stable airflow, balanced operation, low noise levels and energy-efficient operation over the long term.
The unit is equipped with a counterflow non-enthalpy heat exchanger with a temperature efficiency of up to 90%. The heat exchanger transfers heat between the extract and supply air while keeping both air streams completely separate. It is designed with an emphasis on low pressure losses, contributing to quiet, energy-efficient and effective operation.
System performance parameters with AFL CONSTANT FLOW fans:
RECUBOX® HRV 250 VENT-READY TOP can be equipped with three types of non-enthalpy counterflow heat exchangers.
The individual variants differ in plate material, construction and price. This allows RECUBOX® to be adapted to the specific requirements of a project – from an all-aluminium heat exchanger made by a Czech manufacturer to durable versions with HPS plates.
The heat exchanger is selected during the ordering process.
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| RECUTECH RSK+16-300-25 |
All-aluminium counterflow heat exchanger from the Czech manufacturer RECUTECH A robust heat exchanger with aluminium plates and an aluminium casing. It offers high mechanical durability, a long service life and very good thermal conductivity.
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| RECUTECH RSF+16-300-H-F-29 |
Counterflow heat exchanger with HPS plates from the Czech manufacturer RECUTECH A lightweight, hygienic and corrosion-resistant heat exchanger with plastic HPS plates. It is suitable for standard residential and commercial applications where long-term stability and easy maintenance are important.
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| ZERN ENGINEERING HU-EX6 366/300 |
Counterflow heat exchanger with HPS plates and HPS casing The fully plastic design from ZERN ENGINEERING offers high resistance to corrosion and moisture. The heat exchanger is a practical and affordable choice for efficient non-enthalpy heat recovery.
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The casing is prepared so that the fans can be installed very quickly without complicated modifications. AFL CONSTANT FLOW fans are installed simply by inserting them into the prepared opening and securing them in place.
All connections and the condensate drain are designed symmetrically, allowing you to choose the final orientation of the unit during installation. RECUBOX® can also be operated with external fans according to your own system design.
EC fan control is very simple using a DC 0–10 V signal. The unit can be controlled, for example, by:
Product delivery: RECUBOX® HRV 250 VENT-READY TOP is supplied with an integrated heat exchanger, but without fans and without a control unit. The fans and control system can be purchased separately and easily installed by the user.
As standard, RECUBOX® is also prepared for measurement, cabling and safe electrical installation. Thanks to well-designed details, installation of sensors, cable routing and fan wiring are quick, clear and technically clean.
The unit therefore simplifies not only the initial installation, but also future servicing, modifications and system extensions.
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Drawing showing the position, number and design of the cable glands. |
RECUBOX® HRV 250 VENT-READY TOP is also available in a version with a 100% mechanical BY-PASS. This sophisticated system simultaneously closes the fresh-air passage through the heat exchanger and opens a large bypass channel behind the heat exchanger.
The advantage is that even when the BY-PASS is active, the air continues to be filtered by the same filter as during normal operation through the heat exchanger.
Removable BY-PASS mechanism
The entire mechanism can be completely removed from the RECUBOX® in one movement, just like the other components. This makes servicing, inspection and cleaning exceptionally easy.
The mechanism is structurally prepared for installation of any actuator with a minimum torque of 5 Nm. The actuator is mounted on a prepared 10 mm thick plastic plate and secured against rotation using the supplied metric screw. Compatibility with a 14 mm diameter shaft is required.
Casing airtightness is essential for efficient heat recovery. RECUBOX® is equipped with robust adjustable toggle latches, which allow the pressure of the lid against the seal to be precisely adjusted. This prevents unwanted air leakage and allows the unit to operate at the highest possible efficiency.
Thanks to their robust construction, high quality and hygienic safety, our RECUBOX® units are used in a number of CTU projects, including the unique S.A.W.E.R. system developed by UCEEB for producing drinking water from air.
We provide an extended 12-year warranty on the airtightness of RECUBOX® unit casings.
The casing is made of high-quality polypropylene and joined using hot-gas welding technology, creating homogeneous, strong and long-term stable joints without the risk of degradation.
Unlike constructions using glued joints, sealing tapes or combinations of different materials, RECUBOX® maintains its airtightness and mechanical durability even after many years of operation.
RECUBOX® HRV 250 VENT-READY TOP is not just a casing prepared for fans. It is a well-engineered foundation for exceptionally comfortable, stable and technically advanced heat recovery ventilation. The true strength of the entire VENT-READY concept becomes fully apparent when it is equipped with AFL EC CONSTANT FLOW fans.

Main benefit of CONSTANT FLOW technology:
AFL fans automatically maintain a constant airflow even when pressure losses in the system change. This means that the unit continues to operate stably even when filters gradually become clogged, operating conditions change or resistance in the ventilation ductwork fluctuates.
This is a major advantage over conventional fans, where the system has to be carefully balanced and every change in resistance can reduce performance or disturb balanced operation. With AFL CONSTANT FLOW fans, you get much more stable operation, more reliable air exchange and greater comfort without unnecessary adjustments to the settings.
| Constant airflow | The fans automatically compensate for changes in system resistance and maintain the set airflow without constant readjustment. |
| Automatic balanced operation |
Balanced operation is very simple with the VENT-READY system and AFL CONSTANT FLOW fans. Both fans can be connected to the same control signal from any suitable controller. If both fans receive the same control signal value, they automatically maintain the same airflow. This applies even when each fan has to overcome different duct or filter resistance. |
| Lower noise levels | At lower resistance, the fan automatically reduces its speed, allowing the system to operate more quietly and smoothly. |
| Lower energy consumption | When high performance is not required, the fan does not consume unnecessary energy. The result is more energy-efficient operation. |
| Full controllability | The Constant Flow function operates throughout the entire control range, making it easy to adapt the unit's performance to the current needs of the building. |
Practical result for the user:
When you choose RECUBOX® HRV 250 VENT-READY TOP and equip it with AFL EC CONSTANT FLOW fans, you get an exceptionally smart combination: an extremely durable, hygienic and easily serviceable RECUBOX® unit together with fans that automatically maintain stable airflow. The result is modern heat recovery ventilation with a high level of comfort, low noise and without unnecessarily complicated balancing.
See why AFL CONSTANT FLOW fans are so exceptional for RECUBOX® VENT-READY.
The video demonstrates the principle that allows the fans to automatically respond to changes in system resistance and helps maintain stable heat recovery performance over the long term.
VENT-READY really makes sense with AFL CONSTANT FLOW. It is not just about mechanical compatibility, but about a complete functional system that delivers more stable airflow, quieter operation, lower energy consumption and a simpler route to professionally functioning balanced heat recovery ventilation.
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Easy heat exchanger removal The heat exchanger can be quickly and easily removed from the RECUBOX® unit in one movement. |
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Maximum hygiene The non-enthalpy heat exchanger can be easily removed, thoroughly rinsed with water and reinstalled. The interior of the unit remains easily accessible for regular cleaning. RECUTECH heat exchangers are certified with an ILH Berlin hygiene certificate. |
| Mechanical sealing without adhesives The heat exchanger is sealed using a gasket fitted into a groove, without adhesives or self-adhesive sealing tapes. The gasket can be easily replaced if necessary. |
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| No screws, rivets or adhesives RECUBOX® is manufactured from a single type of material using hot-gas welding technology. The result is airtight and permanently stable joints without degradation due to ageing. |
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| Wide range of sizes The VENT-READY range is available in several performance variants, and larger custom versions can also be manufactured for higher airflows. |
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Compatibility with RECUTECH and other heat exchangers The units are designed for high-quality RECUTECH heat exchangers with EUROVENT certification and other compatible heat exchangers according to the specific configuration. |
| Balanced operation When AFL CONSTANT FLOW fans are used, stable and balanced operation of the entire heat recovery ventilation system can be achieved very easily. |
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| Option to install an ioniser The unit can be supplemented, for example, with a MALAPA IN03 ioniser. |
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| Maximum versatility The position of the inlet and outlet ports can be adapted to the specific installation in a wide range of configurations. |
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| Reversible configuration The unit can be connected in either left-hand or right-hand orientation during installation. The condensate drain is provided by a 1/2" connection in two positions. |
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| Easy installation The unit is prepared for installation using threaded rods and allows easy positioning in a technical space. |
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| Large-area filters The unit allows the use of various filter media. As standard, it is equipped with M5 filter media. |
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BY-PASS A bypass insert or integrated 100% BY-PASS is available. |
Example installation of RECUBOX® VENT-READY with REX EC control in a family house.
Click the diagram to enlarge.
The dimensions and construction of the specific variant are shown in the relevant technical drawing.
The final dimensions may depend on the selected connection port diameter, insulation thickness and the version with a 100% BY-PASS. If the selected configuration requires a structural modification, we will contact you before production begins.
The variant is selected during the ordering process.
Front view of the RECUBOX® with the access door open.
The dimensions shown include 50 mm insulation and the second casing. If the dimensions change, for example due to larger connection ports or another technical modification, we will inform you after the order has been placed.
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RECUBOX® TOP – all 4 ports face upwards Dimensions: 743 (A) × 570 (B) × 590 (C) mm – width × height × depth The drawing shows both standard and reversed connections, which can be implemented without modifying the unit. |
RECUBOX® HRV 360 VENT-READY TOP is also available in two versions with a 100% BY-PASS.
Below you will find drawings of both variants including dimensions. The dimensions include 50 mm insulation. The RECUBOX® is shown from above.
Prices are final and include the integrated heat exchanger, all costs, taxes and fees.
Data sheet
Read verified reviews from those who have purchased from us.
regulation for a system with EC fans, frost protection or BY-PASS control programming of ventilation intensity, monitoring filter replacement, quick ventilation - control from the toilet,
Highly efficient EC fan AFL CONSTANT FLOW , designed for installation in the RECUBOX® 250 VENT-READY unit.Thanks to intelligent regulation, it maintains a constant flow rate of 250 m³/h...