RECUBOX® X-POOL HRV 800 – heat recovery box for swimming pools
All-plastic RECUBOX® variant
Chemically resistant RECUBOX® suitable for swimming pools
Absolute resistance to chlorine
Airflow rate up to 1000 m³/h.
RECUBOX® X-POOL HRV 800
RECUBOX® X-POOL HRV 800 is a professional plastic heat recovery module designed primarily for ventilation and heat recovery in swimming pools, wellness centers, water parks, spas, and other high-humidity spaces.
At the heart of the module is a large-surface plastic counterflow heat exchanger, the ZERN HU-EX 366/800, with heat transfer surfaces made of HPS material. The material used is suitable for long-term operation in a humid pool environment and is not at risk of corrosion caused by condensate or typical chlorine vapors.
Why Choose RECUBOX® X-POOL HRV 800
- Designed specifically for swimming pools, wellness centers, and permanently humid facilities
- ZERN plastic counterflow exchanger with no risk of corrosion on heat transfer surfaces
- High thermal efficiency of approximately 87.5–88% at the recommended airflow rate
- Recommended nominal airflow rate of approximately 800 m³/h
- Robust welded construction without screws, rivets, or structural adhesives
- Easy cleaning and high hygienic standard
- Simple installation and easy servicing
- High flexibility in configuration and connection spigot placement
- Long service life even during continuous operation in humid environments
Construction and Material Design
The entire casing of the module, flanges, filter frames, mounting brackets, and other structural components are made of high-quality polypropylene (PP). The construction is designed without unnecessary metal parts, emphasizing maximum resistance to moisture, condensate, and swimming pool environments.
The casing material is highly resistant to:
- permanently high air humidity,
- condensate generated during pool heat recovery operation,
- chlorine vapors in typical pool concentrations,
- salt spray and corrosive humidity,
- standard cleaning and disinfectant agents used in pool facilities.
The construction utilizes 100% welded joints. The module contains no conventional glued structural joints, rivets, or unnecessary metal fasteners that could be subject to corrosion or degradation under long-term exposure to moisture.
All essential sealing elements are mechanically engineered and easily replaceable. Smooth interior walls facilitate regular cleaning, inspection, and hygienic maintenance.
Important notice: RECUBOX® X-POOL HRV 800 is designed primarily for swimming pool, wellness, and similar humid environments. The ZERN HU-EX 366/800 plastic exchanger is suitable for pool environments, but it is not intended for the chemical industry with high concentrations of highly aggressive acids, bases, solvents, or other strongly reactive substances. For such applications, the chemical composition of the exhaust air must be evaluated individually.
Thanks to their robust construction, high quality, and maximum hygienic safety, our RECUBOX® modules are part of numerous CTU (Czech Technical University) projects, including the unique S.A.W.E.R. system developed by UCEEB to extract drinking water from the air.
ZERN HU-EX 366/800 Heat Exchanger
RECUBOX® X-POOL HRV 800 is equipped with a large-surface ZERN HU-EX 366/800 plastic counterflow heat exchanger, suitable for long-term operation under high humidity in swimming pool environments.
The heat transfer surfaces of the exchanger are made of HPS material. Unlike conventional metal exchangers, the heat transfer surfaces are therefore not at risk of typical corrosion caused by condensate, high humidity, or common chlorine vapors.
- Plastic heat transfer surfaces made of HPS material
- High resistance to continuous moisture and condensate
- Suitable for standard pool environments
- Zero corrosion of heat transfer surfaces
- Counterflow arrangement for achieving high thermal efficiency
- Large heat transfer area optimized for an airflow rate around 800 m³/h
- Easy inspection, removal, and cleaning
ZERN HU-EX 366 plastic counterflow exchanger
Recommended Operating Airflow
For the ZERN HU-EX 366/800 exchanger, we recommend an operating airflow rate of approximately 700–900 m³/h, with the optimal design point around 800 m³/h.
At this flow rate, based on the performance characteristics of the exchanger, you can expect approximately:
- thermal efficiency around 87.5–88%,
- pressure drop of approximately 135–165 Pa depending on the flow side,
- an excellent balance between air performance, efficiency, noise level, and fan power consumption.
At an airflow rate of 1,000 m³/h, the exchanger remains functional; however, the pressure drop increases to approximately 185–200 Pa, and thermal efficiency drops to approximately 86.3%.
We therefore recommend considering this airflow rate as a higher operational limit rather than an ideal continuous design point. When selecting fans, it is necessary to factor in the pressure losses of filters, ductwork, distribution elements, and other components of the complete HVAC system.
| Operating Mode | Recommended Volumetric Airflow |
| Economical and quiet operation | 600–750 m³/h |
| Recommended nominal airflow | approx. 800 m³/h |
| Higher operating airflow | 900–1,000 m³/h |
| Operation above 1,000 m³/h | Only with sufficient fan pressure margin and assuming higher noise levels and power consumption are acceptable. |
RekupeX Recommendation: For standard continuous operation, we recommend designing the module for approximately 800 m³/h. At this design point, the exchanger offers an optimal balance between high efficiency, low pressure drop, and fan energy demand.
Installation and Maintenance
- Fans are not included with the module – they are installed separately directly into the HVAC ductwork.
- Separate fan installation allows for flexible placement considering noise reduction, servicing, and utility room space.
- If necessary, fans can be quickly replaced without modifying the RECUBOX® module itself.
- The module is designed for easy service access, regular inspection, and straightforward maintenance.
- The exchanger can be removed from the module for inspection or cleaning as needed.
- The condensate drain must be connected to an appropriate trap and routed with the correct slope.
Plastic Alternative to Metal Pool Units
Thanks to the properties of polypropylene and the plastic heat exchanger, the RECUBOX® X-POOL HRV 800 is an appealing alternative to metal or all-stainless-steel pool heat recovery solutions.
Under long-term exposure to high humidity, condensate, and chlorine vapors, metal structural parts can undergo gradual surface degradation or corrosion. In contrast, the high-quality polypropylene casing and plastic heat transfer surfaces maintain their stability and functionality over time.
Furthermore, the module contains no integrated complex electronics or fans. This allows the entire system to be customized to the required airflow, room layout, and specific pool technology needs.
A Perfect Choice For
- Private indoor swimming pools
- Hotel pools and wellness centers
- Public pools and swimming complexes
- Water parks and aquatic attractions
- Spas and rehabilitation centers
- Hot tub and relaxation facilities
- Saunas and steam rooms, provided they fall within the allowed temperature range of the exchanger and module
- Pool utility rooms
- Dehumidification and ventilation systems for pool halls
- Other continuously humid facilities free from highly aggressive chemical substances
Main Advantages of RECUBOX® Modules
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Easy exchanger removal The exchanger can be removed from the module very quickly and easily, making regular inspection, maintenance, and cleaning straightforward. |
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Maximum hygiene Smooth interior walls and easily accessible components allow for thorough cleaning. This is especially important in pool and wellness facilities with strict hygiene requirements. |
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Mechanical sealing without adhesives The exchanger is sealed using mechanically secured sealing elements without stick-on gaskets that could degrade over time. Seals can be easily replaced if needed. |
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Without screws, rivets, or structural glues The RECUBOX® casing is manufactured from polypropylene using hot gas welding technology. The result is strong, airtight joints with zero risk of fastener corrosion. |
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Custom-engineered dimensions The module can be structurally adapted to the specific spatial constraints of the utility room, required spigot diameters, and mounting orientation. |
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Designed for ZERN HU-EX 366/800 exchanger Internal construction, airflow routing, exchanger seating, and service access are tailored specifically to the dimensions and features of the ZERN plastic exchanger. |
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Performance optimized for pool applications The recommended operating range of approximately 700–900 m³/h is well suited for small to medium-sized private, hotel, and commercial pool installations. |
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Maximum flexibility Inlet and outlet spigot locations can be configured based on the specific application, duct routing, and technical room space. |
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Mirrored version Select variants are also available in a mirrored orientation. The condensate drain features a threaded connection, positioned according to the module's orientation. |
Additional Practical Advantages
Easy installation thanks to pre-fitted mounting elements and the option to adapt the structure to specific hanging or standing arrangements.
Large-surface filters reduce air velocity across the filter medium, extending replacement intervals and reducing overall system pressure drop. In the standard configuration, the module includes M5 class filter media.
Separately installed fans allow performance, control, and pressure margins to be selected precisely according to the specific HVAC system.
100% BYPASS can be implemented as a separate bypass module or as an integrated component with actuator control, depending on the project.
Fan Selection & Sizing
Fans must be sized not only according to the required volumetric flow rate, but also to match the total pressure drop of the complete HVAC system.
When selecting fans, the following pressure losses must be accounted for:
- pressure drop of the ZERN HU-EX 366/800 heat exchanger,
- pressure drop of filters in clean and dirty states,
- pressure losses in ductwork and fittings,
- pressure losses of diffusers, grilles, and weather louvers,
- reheaters, dampers, sound attenuators, and other accessories,
- necessary control and performance margin.
For nominal operation around 800 m³/h, we recommend choosing fans with sufficient pressure reserve beyond the exchanger's pressure drop alone. Specific sizing depends on the duct system length and layout.
Pressure Drop Graph
Pressure drop PD [Pa] vs. volumetric airflow rate AV [m³/h] – ZERN HU-EX 366/800 exchanger
Thermal Efficiency Graph
Thermal efficiency EFF [%] vs. volumetric airflow rate AV [m³/h] – ZERN HU-EX 366/800 exchanger
At an airflow rate around 800 m³/h, thermal efficiency is expected to be approximately 87.5–88%. Increasing the airflow to 1,000 m³/h reduces efficiency to approximately 86.3%.
Data Sheet
Operating parameters of ZERN HU-EX 366/800 exchanger at 800 m³/h airflow
Outdoor air: 7 °C, relative humidity 75%. Indoor air: 20 °C, relative humidity 37%.
Spigot Connection Configurations
Configuration selection takes place during the ordering process.
Front view of RECUBOX® with the service door open.
Stated dimensions include 50 mm thick insulation and the double-walled casing. If dimensions change due to larger connection spigots or other technical modifications, we will inform you after placing the order.
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A01 Exchanger on a wide drain tray, 4 side spigots Dimensions: 551 (A) × 551 (B) × 992 (C) mm – width × height × depth Drawing shows both standard and mirrored configurations. |
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B01 Exchanger on a narrow drain tray, 4 side spigots Dimensions: 551 (A) × 551 (B) × 992 (C) mm – width × height × depth Drawing shows both standard and mirrored configurations. |
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A02 Exchanger on a wide drain tray, 2 top spigots, 2 side spigots Dimensions: 551 (A) × 551 (B) × 992 (C) mm – width × height × depth Drawing shows both standard and mirrored configurations. |
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B02 Exchanger on a narrow drain tray, 2 top spigots, 2 side spigots Dimensions: 551 (A) × 551 (B) × 992 (C) mm – width × height × depth Drawing shows both standard and mirrored configurations. |
Service Access and 100% BYPASS Dimensions
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Service Access – dimension E Sufficient clearance must be maintained in front of the RECUBOX® service door to slide the exchanger out of the module. E = C − 60 mm Integrated 100% BYPASS – dimension F The integrated BYPASS is located behind the heat exchanger, increasing the final depth of the module depending on the specific configuration. Exact final dimensions of RECUBOX® with integrated BYPASS will be provided based on your chosen configuration. The BYPASS opens a fresh air bypass route around the exchanger while closing off the pathway through the exchanger. |
Custom Manufacturing
RECUBOX® X-POOL HRV 800 is manufactured according to your selected configuration. Spigot positions, service door orientation, condensate drain location, insulation type, and other structural details can be tailored to the specific installation.
If the selected configuration cannot be technically realized or if an alternative solution would be more suitable, we will contact you prior to starting production.
Data sheet
- Material
- SIMONA AlphaPLUS - POLYPROPYLENE
- Operating temperature [°C]
- -20 .. +80
- Country of origin
- CZ
- Zero corrosion risk: This fan does not come into contact with chlorine or pool humidity, because it works exclusively with outdoor air.
- Choice: A standard high-quality inline duct fan is sufficient for this position without the need for special chemical resistance.
- Filtration barrier: Air from the pool first passes through filter fabric, which mechanically captures aerosol (microdroplets of water with concentrated chlorine).
- Condensation cleaning: In the heat recovery exchanger, the air cools down and the moisture condenses. This water binds gaseous chlorine to itself and safely drains it away into the wastewater system.
- Result: The fan placed after the RECUBOX works with significantly “cleaned” air, which protects its motor and bearings.
What fans should be selected for pool ventilation?
The selection of fans for pool areas is critical due to the high humidity and the presence of aggressive chlorine. However, when using the RECUBOX® X-POOL unit, the design of the unit significantly changes the fan resistance requirements in your favor.
1. Fan for supply air (fresh air)
In this part of the system, the situation is the simplest. The supply fan draws in clean outdoor air and pushes it through the heat recovery exchanger into the pool hall.
2. Fan for exhaust air (waste air)
Thanks to the unique integration with the RECUBOX® X-POOL unit, the exhaust fan is protected in a way that significantly extends its service life:
Recommendations for installation and maintenance
Key rule: RECUBOX® as the lowest point of the system
For proper operation, the RECUBOX® unit must be installed at the lowest point of the air handling route. Only then can the ducting naturally drain all aggressive condensate with chlorine towards the unit and subsequently into the drain. This prevents moisture from accumulating near the fans or at critical duct joints.
| Duct material | For the exhaust branch, we recommend exclusively plastic (PVC/PP) or stainless steel ducting. Aluminum ducting is subject to rapid corrosion. |
| Fan type | We recommend choosing fans in an all-plastic design with protection rating at least IP44. |
| Filter maintenance | Regular inspection of the filter fabric is essential in pools to maintain the cleanliness of the exchanger as well as fan protection. |
Our professional view: The combination of the durable RECUBOX® X-POOL design and suitably selected plastic fans represents the technically cleanest solution for modern pools. This configuration saves costs because it eliminates the need for extremely expensive industrial fans intended for the chemical industry.
Note: The above information represents the manufacturer’s recommended technical practice for extending component service life. The final fan selection should always correspond to the HVAC design and the expected concentration of chemical substances in the specific installation.
What ducting should be used for pool ventilation?
The choice of ductwork material is just as important for a swimming pool as the heat recovery unit itself. An aggressive environment with chlorine content combined with high humidity can destroy improperly selected ducting within a few months.
Why avoid aluminum and cheap “flex” hoses?
Commonly used aluminum flexible ducts (so-called Alu-flexi, Sono-flexi) are completely unsuitable for pool environments. Chlorine vapors cause rapid oxidation of aluminum, which appears as white powder formation followed by perforation of the duct wall.
Warning about leaks: Once corrosion occurs, the system loses pressure balance, humidity in the building structure increases, and mold may develop around leaking duct sections.
Recommended materials for RECUBOX® X-POOL
For long-term reliable operation of pool ventilation, we recommend using materials that naturally resist corrosion:
| Plastic ducting (PVC / PP) | Ideal choice for pools. Smooth plastic ducts are 100% resistant to chlorine and moisture and have minimal pressure losses. |
| Stainless steel ducting | Premium solution with extreme mechanical durability. Suitable for exposed design ducting in interior spaces. |
| Insulated EPE ducting | Excellent for routes passing through unheated areas. Foamed polyethylene is non-absorbent and chemically resistant. |
Important: Slope and condensate drainage
Gravity works for you:
All horizontal duct runs must be sloped towards the RECUBOX® unit (minimum slope 1–2%). Since the RECUBOX® is installed at the lowest point, all condensate containing chlorine compounds flows smoothly into the exchanger and directly into the drain. This prevents the formation of “pockets” of standing water inside the ductwork.
Practical tip: If flexible ducting must be used in certain places (e.g. for connections), always use plastic flexible hoses or hoses with a chemically resistant inner layer. This will help you avoid costly repairs in ceiling spaces in the future.
Note: Proper selection of duct material is crucial to maintain the 12-year warranty on the airtightness of the RECUBOX® unit casing. Inappropriate ducting may negatively affect the hygiene of the entire system.
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All-plastic RECUBOX® variant
Chemically resistant RECUBOX® suitable for swimming pools
Absolute resistance to chlorine
Airflow rate up to 1000 m³/h.