Contrary to heat pipes, plate heat exchangers (recuperators) and rotary heat exchanger (regenerator) no junction of the air flows is required at the bildings energy recovery system for coil energy recovery loop systems. Through the absolute separation of extract air flow and outdoor air flow the coil energy recovery loop system is the firs choice for buildings with high hygienic demands. As the several heat exchangers are connected to each other by a heat transfer fluid (brine), feed-in and feed-out of thermal energy in the coil energy recovery loop system is possible. In table 1 different energy recovery systems are compared.

• Friterm Highly efficient heat exchanger with new system M3535, tube arrangement in-line.
• Temperature efficiency up to 80 % through special circuitry with high counter flow ratio.
• Copper tubes, diameter 12 mm (15 mm optionally available).
• Flat aluminium fins, 0.20 mm thick, up to 12 (optional 18) rows in air direction out of one fin, according VDI 3803-1: 2010-02.
• Applicable for hygiene areas, cleanable.
• Internal venting and draining.
• System optimized for low air side pressure drop, therefore exceptionally economical (low life cycle costs).
• Special design on request.