New iMCHE from Danfoss offers maximum part-load efficiency

Date: 20 December 2019

The interlaced microchannel heat exchanger (iMCHE) integrates a chiller or rooftop unit's multiple circuits into a single coil with a shared air heat transfer area, controlling each circuit independently. Using the whole air side heat transfer area when operating under part-load conditions, iMCHE is able to maximize system efficiency.

The iMCHE provides a compact and cost-effective solution for dual-circuit rooftop units. Dual-circuit rooftop units typically have two refrigerant circuits, each with one or more compressors. Under a full load, the iMCHE performs similarly to a conventional heat exchanger, while under part-load conditions, the system turns off one circuit, stopping portion of the tubes in the iMCHE. The remaining tubes operate with whole air side heat transfer area, maximizing both efficiency and performance.

Compared to standard tube and fin heat exchangers, the iMCHE has clear advantages, from its compact, lightweight, all-aluminum design to its high efficiency heat transfer and lower refrigerant charge. The iMCHE delivers flexibility for different system circuit setups with its tube bending structure and passage setup, as well as its multi-row compact structure and high-tolerance distributor solution in evaporator applications.

Based on its excellent performance under part-load conditions, particularly when used with IDV scroll compressors, the iMCHE can significantly increase a system's IEER efficiency rating by nearly 20%. This means existing systems meeting current standards will have no trouble meeting new, stricter energy efficiency standards simply by upgrading to an iMCHE with minimal redesign costs.

The modularity, customizability, and extensive flow arrangements of this new heat exchanger offer countless possibilities, addressing the many unique challenges facing the Chiller and Rooftop industry.