Following a review of the listed part codes, there are no functional capacity conflicts; however, there are clear generational, design, and interface differences that should be considered when specifying or supporting these models.


1. Product Family Overview

All four part codes are:

  • Large chassis VRF cassette indoor units

  • Designed for higher-capacity commercial applications

  • Comparable in capacity, but not equivalent in generation or feature set


2. Older Generation – 4-Way Flow Cassette (Legacy Platform)

Models:

  • AUXD24GALH

  • AUXA24GALH

Key Characteristics:

  • Traditional 4-way discharge cassette

  • Historically the standard choice for large-capacity cassette applications

  • Older generation control platform

  • No UART interface (limits advanced integration and controls capability)

  • Functional and reliable, but now considered legacy design


3. Newer Generation – Circular Flow Cassette (Current Go-To)

Models:

  • AUXM024GLEH

  • AUXK024GLEH

Key Characteristics:

  • Circular Flow Cassette design

  • Current preferred solution for large-capacity VRF cassette applications

  • Includes UART interface, enabling improved integration, controls, and future-proofing

  • More recent platform with:

    • Improved control compatibility

    • Enhanced system integration options

    • Significantly improved aesthetics


4. Slim vs Normal Chassis (Applies Across Both Ranges)

Both the older and newer cassette ranges are available in Slim and Normal chassis variants.

VariantCharacteristicsConsiderations
SlimReduced unit heightLower airflow capacity
NormalTaller chassisHigher airflow and potentially marginally different sound levels

Implication:

  • Selection should be based on ceiling constraints, airflow requirements, and acoustic expectations.


5. Recommended Guidance

  • For new projects:
    ? Specify AUXM / AUXK Circular Flow Cassettes wherever possible.

  • For replacement or matching existing systems:
    ? AUXD / AUXA may still be appropriate where integration limitations are acceptable.

  • Where controls, BMS integration, or future upgrades are a priority:
    ? Avoid AUXD / AUXA and specify AUXM / AUXK.


6. Summary Statement

In short, the differences are not capacity-related, but rather:

  • Generation

  • Control interface capability

  • Airflow design

  • Aesthetic and integration maturity

This distinction should be clearly communicated during specification, quoting, and service discussions to ensure the correct product is selected for the intended application.