The fourth edition of UL 60335-2-40, the Standard for Household and Similar Electrical Appliances - Safety - Part 2-40: Particular Requirements for Electrical Heat Pumps, Air-Conditioners and Dehumidifiers, was published on December 15, 2022. This bi-national standard includes the following updates:
- Updated definition and test method for releasable charge with relation of refrigerant leaks into the occupiable space
- Refinement of leak detection system requirements to accommodate various methods, increase robustness and reliability, and account for deviation and drift over the system lifecycle
- Clarification of potential leak point definition and requirements, and leak sensor location requirements
- New combined flame symbol markings for fire service identification
- Leakage current requirements for permanently connected appliances
- Mechanical strength and vibration tests
- Safety shut-off valve requirements for limiting the releasable charge
- Audible alarm requirements
These updated requirements will be mandatory for all new certifications of these products by UL Solutions after January 1, 2025.
Products certified to UL 1995
Special note: Because the previous standard for these products, UL 1995, the Standard for Heating and Cooling Equipment, does not address refrigerants other than class A1, UL 1995 is no longer being maintained and will not be used for new certifications after January 1, 2025.
Products certified to UL 1995 before this date may be allowed to have continuing certification until January 1, 2028, in alignment with the EPA’s allowed sell-through date.