Brazed plate heat exchangers are the perfect solution that allows for maintaining high thermal performance at low operating costs.
The HEXONIC L series is our core copper-brazed plate heat exchanger, engineered for liquid-to-liquid heat transfer across a wide range of heating, cooling, and domestic hot water applications. Built with precision vacuum-brazed corrugated stainless steel plates, the L series combines exceptional thermal efficiency with an extremely compact footprint and long service life requiring virtually no maintenance.
Available in a broad range of plate counts and connection sizes, the L series is the standard specification for district heating substations, heat interface units (HIUs), heating and cooling circuits, and indirect domestic hot water systems in residential, commercial, and light industrial buildings worldwide.
Key Features
- High thermal efficiency: Deeply embossed corrugated plate geometry maximises turbulence and heat transfer coefficient, delivering more heat duty per unit of installed area than shell and tube alternatives
- Exceptionally compact: The L series occupies a fraction of the space of equivalent shell and tube exchangers, making it ideal for wall-mounted plant rooms, compact skid packages, and space-constrained installations
- Maintenance-free operation: Vacuum-brazed construction with no gaskets, no bolts, and no moving parts. In clean, treated water circuits the L series requires only periodic chemical CIP cleaning — no disassembly or part replacement
- Wide operating range: Rated for operating temperatures from -195°C to +230°C and standard working pressures up to 45 bar — covering the full range of HVAC and light industrial heating and cooling duties
- Flexible specification: Available in a wide range of plate counts (from 10 to 400+ plates), connection sizes, and flow configurations to match any system requirement precisely
- Compatible with glycol circuits: Fully compatible with inhibited propylene glycol and ethylene glycol solutions at standard concentrations used in frost protection and cooling systems
- Reliable - adapted to operate in demanding conditions of temperature and pressure differences
- Optimized for any use – thanks to the single- and double-flow versions, wide range of connections and the selection of proper number of plates.
High efficiency compared to shell and tube heat exchangers
lower height of the exchanger, with the same heat exchange area
more performance, with the same heat exchange area
higher value of the heat exchange coefficient
Design
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Copper or stainless LUNATM brazing
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Connections
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Heating plates
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Cover plates
How does the brazed plate heat exchanger work?
Brazed plate heat exchangers in heating systems
Technical Specifications
| Parameter | Specification |
|---|---|
| Design Standards | ASME; UL; PED; EAC |
| Max Design Pressure | 30 bar/ 435 psi |
| Max Design Temperature | 230°C/ 446°F |
| Heating plates Materials | stainless steel 1.4404 (AISI 316L), copper brazing |
| Front and Rear Plate Materials | stainless steel 1.4301 (AISI 304) |
| Design Types | 1-pass; 2-pass with 4 connections; 2-pass with 6 connections; |
| Connection Types | external thread / external thread (NPT): from 3/8″ to 5/2″ internal thread / internal thread (NPT): from 3/8″ to 2″ dual connections (external thread and soldering): from 3/8″ to 5/2″ Victaulic: from 3/4″ to 5/2″ flange: DN50 PN40 Type 11B / ANSI B16.5 2″ Class 300 SORF to DN150 PN40 Type 11B / ANSI B16.5 6″ Class 300 SORF soldering connection for R heat exchangers: from 1/4″ to 3 5/8″ |
| Certification | ASME; UL; PED; EAC |
Frequently Asked Questions
The L series is optimised for liquid-to-liquid heat transfer — both circuits carry single-phase liquids such as water or glycol solution. The R series is designed for refrigerant two-phase applications (evaporation and condensation) and features a different corrugation pattern optimised for refrigerant boiling and condensing heat transfer characteristics.
For potable water applications, HEXONIC recommends SafePLATE (double-wall design) or the all-stainless-steel LUNA series. The standard copper-brazed L series should not be treated as a universally suitable solution for direct contact with potable water, as its acceptability depends on local requirements and approvals.
Use HEXONIC’s CAIRO online selection tool (cairo.hexonic.com) — input your thermal duty, fluid types, inlet/outlet temperatures, and maximum pressure drop, and CAIRO will identify the optimum L series model and plate count. Contact the HEXONIC engineering team for complex or custom sizing requirements.
In clean, treated water circuits, the L series can be cleaned in-place (CIP) using approved alkaline and acid cleaning agents circulated through the exchanger. Do not use mechanical cleaning methods (wire brushes, scrapers) or chlorinated cleaning agents above approved concentrations. Consult the HEXONIC maintenance guide for full CIP procedure.


