Effective July 29, 2016

Standard Information
Standard Number:
UL 484
Standard Name:
Room Air Conditioners
Standard Edition and Issue Date:
9th Edition Dated February 7, 2014
Date of Revision:
July 31, 2015
Date of Previous Revisions to Standard:
9th Edition Dated March 6, 2014
Effective Date of New/Revised Requirements

Effective Date (See Schedule below): July 29, 2016

Impact, Overview, Fees and Action Required

Impact Statement: A review of all Listing Reports is necessary to determine which products comply with new/revised requirements and which products will require re-evaluation. NOTE: Effective immediately, this revised standard will be exclusively used for evaluation of new products unless the Applicant requests in writing that current requirements be used along with their understanding that their listings will be withdrawn on Effective Date noted above, unless the product is found to comply with new/revised requirements.

Overview of Changes: The revisions include the addition of supplement for requirements for alternative path for electronic controls, as well as revisions to requirements regarding flammable refrigerants. Specific details of new/revised requirements are found in table below.

Schedule: So that shipping of products with Listing Marks will not be interrupted, an approximate schedule has been established to ensure Listing Reports are found compliant by Effective Date:

  • November 30, 2015 = 8 Month Report Review – Intertek will review all Reports. Update if compliance is verified or issue Findings Letter/Quote for any re-evaluations needed
  • January 29, 2016 = 6 Month Quote Cut-off – Quotes returned for necessary re-evaluations
  • June 30, 2016 = 30 Day Warning – Client advised of all non-compliant Reports to be Suspended
  • July 29, 2016 = Effective Date – ATM Suspended for all non-compliant Reports 

Fees: An initial review of Listing Report (s) will be covered by a direct billing project and will be invoiced at not more than $1000 per report.

Client Action Required:

Information – To assist our Engineer with review of your Listing Reports, please submit technical information in response to the new/revised paragraphs noted in the attached or explain why these new/revised requirements do not apply to your product (s).

Current Listings Not Active? – Please immediately identify any current Listing Reports or products that are no longer active and should be removed from our records. We will do this at no charge as long as Intertek is notified in writing prior to the review of your reports.

Description of New/Revised Technical Requirements
--UL 484 has been revised primarily to limit the amount of flammable refrigerant that can be used. These changes are reflected in clause 36.2, Supplement SA, and Appendices A, C, D and E.
36.2 New clause added;

Refrigerants are categorized for toxicity as either lower toxicity or higher toxicity in accordance with the Standard for Number Designation of Refrigerants, NSI/ASHRAE 34. Refrigerants intended for use in room air conditioners shall be in the lower toxicity group, Group A.


The changes eliminate all the room area and installation height criteria since the below equation (referenced in Appendix E) would require a charge size based only on the refrigerant LFL.

Revision to reduce the refrigerant charge;
From: m1 = (4 m3) * LFL  
To: m1 = (3 m3) * LFL
(and eliminate the m2 value, which was the previous limit)

• m1         Value of the refrigerant charge limit (kg)
• 4 m3      Constant
• 3 m3      Constant
• LFL        Lower Flammability Limit of the Refrigerant in kg/ m3


  • Since Room Air Conditioners are a consumer purchased and installed product, the working group couldn’t be sure they would be installed in rooms with sufficient area as marked on the product. The working group felt they should be “safe out of the box”.
  • Many Room Air Conditioners are uninstalled and seasonally stored in a storage area. Some of these are quite small and the working group thought a refrigerant leak could be dangerous.
Some U.S. manufacturers were concerned about the relatively large amounts of highly flammable refrigerant allowed, and wanted to pull back to a lesser amount.
SUPPLEMENT SCInfoAddition of supplement for requirements for alternative path for electronic controls

CUSTOMERS PLEASE NOTE: This Table and column "Verdict" can be used in determining how your current or future production is or will be in compliance with new/revised requirements.

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