Counter-flow heat exchangers
95%
Efficiency
ZERN ENGINEERING counter-flow heat exchangers deliver maximum thermal efficiency with complete separation of supply and exhaust air. Built with polystyrene (sensible) or vapor-permeable polymer membranes (enthalpy), they provide reliable energy recovery for residential, commercial, and industrial AHUs/ERVs.
Product categories
Types and variations
Sensible counter-flow heat exchangers
Series:
HU / HS / HC / HD-EX6
Thermoformed polystyrene cores for high heat recovery with low pressure drop. Monolithic, fully sealed structure prevents cross-contamination and is suitable for low- to medium-pressure systems.
Enthalpy counter-flow heat exchangers
Series:
ECD / EC-EX6
Polymer plates bonded with a microporous, vapor-permeable membrane recover both heat and moisture - ideal for cold or dry climates and RH control.
Combi counter-flow heat exchangers
Series:
Combi HU/HC-EX6
Twin-core modules joined by common plenums to handle higher airflows with a lower pressure drop while keeping all counter-flow benefits.
Key operational parameters
Performance сharacteristics
Thermal efficiency
Up to 95% under optimal conditions.
Humidity efficiency
Up to ~80% (depending on modes and RH).
Airflow range
Standard models 50–6,000 m³/h; larger customized solutions available on request.
Operating temperature
−25 °C to +50 °C.
Pressure drop
Typically, 40-150 Pa (depends on airflow and core size).
Service life and maintenance
Сores are non-corrosive, washable and remain effective for many years.
Technical features
Design and structure
Principle of operation
In counter-flow heat exchangers, two air streams flow in opposite directions through thin channels formed by a layered polystyrene or polymer membrane structure. This counter-flow configuration ensures a consistently high temperature gradient across the entire core length, enabling highly efficient heat transfer.
- Sensible models: transfer heat only.
- Enthalpy models: transfer both sensible and latent heat and moisture, while blocking dust, dirt, odours, CO₂ and other gases.
- Optional: bypass and damper enables free-cooling and mode switching.
Core material
Thermoformed polystyrene plates or polymer-based enthalpy plates arranged in a tightly packed structure. The design provides:
- High surface area for effective thermal transfer.
- Low air resistance thanks to an optimized channel geometry.
- No risk of corrosion or germ growth (non-metallic material).
Casing materials
- Polystyrene (HIPS) — lightweight, insulated; ideal for compact residential units.
- Aluzinc steel — economical and corrosion-resistant for long-lasting performance.
- Aluminum — lightweight, corrosion-resistant; good for humid sites.
- Epoxy-coated — for chemically active or coastal areas.
- Stainless steel (AISI 304/316) — for aggressive/hygienic sites.
Main areas of use
Applications
- Residential buildings — apartments, apartment complexes, private homes.
- Commercial facilities — offices, shopping and business centers, schools, cultural institutions.
- Industrial systems — production workshops, warehouses, logistics complexes.
- Hotel and wellness sector — hotels, sports and fitness centers, swimming pools (enthalpy models provide additional humidity control).
- Public spaces — airports, exhibition halls, stadiums, transport hubs.
Product catalog
More information
Discover ZERN ENGINEERING’s full range of heat exchangers. Our product catalog provides detailed specifications, material options, and performance data to help you select the optimal solution for any application