Packless double wound helix & WSHP coil [green surface models ]

Description

Double Wound Helix: Design and Safety

Available High Efficiency Green Surface Models

The double wound helix refers to the construction of the inner tube that facilitates both high efficiency and crucial safety.

• Design: It consists of two layers of convoluted (corrugated) tubing—an inner primary tube and an outer secondary tube—wound helically and stacked one over the other. This creates a secure, double-layer barrier between the two fluid circuits.
• Safety Priority (Potable Water): This is the most critical feature. The double-wall construction ensures that if a leak were to occur in either the inner or outer barrier, the refrigerant (or other fluid) cannot mix with the potable water flowing inside the inner tube. This design is mandatory for codes requiring separation of refrigerant from drinking water.
• Leak Path to Atmosphere: Specific models often include a small leak detection void between the inner and outer walls. If a leak occurs, the refrigerant or water will escape through a detection port to the atmosphere, alerting maintenance personnel without contaminating the potable water supply.

📈 Performance Feature

The convoluted nature of the inner and outer tubes contributes significantly to heat transfer performance:

• Enhanced Heat Transfer: Both the primary inner tube and the secondary outer tube are convoluted. This helical, corrugated shape dramatically increases the surface area available for heat transfer per unit length.
• Increased Turbulence: The convolutions induce significant turbulence in the flow of both the water (inside the primary tube) and the refrigerant (flowing in the annular space).¹
  • Benefit: Turbulence prevents the formation of laminar flow layers, which are poor conductors of heat, thus boosting the overall heat transfer coefficient (²$\text{U}$-value) and efficiency.
• Anti-Fouling: The constant disruption of the flow caused by the helix and convolutions inhibits the accumulation of scale and sediment (fouling) on the heat exchange surfaces, helping maintain peak efficiency over the unit’s lifespan.