Sorry, you need to enable JavaScript to visit this website.

High Efficiency H-Series

h-series hero image

Designed to meet United States Department of Energy (DOE) energy conservation standards for Walk-In Coolers and Freezers (WICF).

High Efficiency H-Series Condensing Units

High Efficiency H-Series  condensing units are designed to meet United States Department of Energy (DOE) energy conservation standards for Walk-In Coolers and Freezers (WICF) which mandates minimum Annual Walk-In Energy Factor (AWEF) ratings for condensing units. The minimum AWEF ratings vary based on application type* (cooler/freezer) and unit location (indoor/outdoor). In-scope are condensing units applied to an enclosed refrigerated space that can be walked into and has a total chilled storage area of 3,000 square feet or less.  Out of scope are water-cooled, remote, and satellite units, a condensing unit serving more than a single refrigeration load or serving refrigerated cases.

Hussmann and its Krack product provide a broad range of condensing unit solutions that meet the minimum AWEF requirements for WICF applications.


  • Broad range of DOE compliant condensing units for WICF applications that have a chilled storage area of 3,000 squarefeet or less
  • Up to five different compressor solutions
  • Condensing units equipped with PSC fan motors operating at ¼ HP and 1075 RPM
  • New front grille design that reduces static air pressure prevalent with legacy H-Series units
  • Multiple refrigerants available including R-404A, R-407A, R-407F, R-448A, R-449A, and R-507A
  • Voltages available in 208/1/60 (Copeland Scroll only), 208/3/60, and 460/3/60



  • Engineered with a deeper pitch, more efficient fan blade design to maximize air flow
  • Over 980 Low and Medium Temperature condensing unit models available that meet DOE AWEF rating compliance for indoor and outdoor applications
  • Electrical panel moved from front to side panel providing greater access for larger compressors for application on medium size bases
  • Outdoor High Efficiency H-Series units now come standard with an adjustable head pressure control / hold back valve
  • Multi-fan High Efficiency H-Series units now come standard with an ambient temperature control for cycling off half the fans at approximately 40 °F using Johnson Controls A421

*Medium temperature: room temperature above 32 °F; Low Temperature: Room Temperature 32 °F and below

Product Resources

Flyer: DOE 2020

Technical Bulletin: HE H-Series Technical Bulletin 

Installation Manual: HE-Series Condensing Unit Manual 

Support CenterModel Specific Electrical and Dimensional Drawings

Mini Outdoor Systems and Krack Catalog

New store installations with refrigerated systems for California beginning 1/1/2022 must not exceed 50 lbs of charge and use a refrigerant below 2,200 GWP. Systems greater than 50 lbs charge require refrigerants below 150 GWP. Existing store compliance for CA requires a reduced weighted average GWP of refrigerants used to less than 1,400 GWP for the fleet by 2030 or a 55% reduction of overall GHGP (charge not relevant).

CARB Sustainable Solutions

Related Content