March 30, 2020
By: Barry Karnes, Principal Engineer of Refrigeration Products
UL announces the publication of a significant number of updates to the eighth edition of UL 207, the Standard for Safety for Refrigerant-Containing Components and Accessories, Nonelectrical. This Standard deals with the safety of nonelectrical refrigerant-containing components and accessories, intended for field or factory installation.
These updates were published within UL 207 on Jan. 21, 2020, and are primarily intended to:
- Document requirements for refrigeration line sets
- Consolidate the requirements for refrigeration fittings into UL 207
- Provide requirements for nonmetallic materials — expected to be particularly applicable to refrigeration line sets
Additional UL 207 revisions clarify and update the following:
- Several marking requirements
- Definitions within the glossary
- Other requirements with minor editorial corrections
Refrigeration line sets — Refrigeration line sets have been certified by UL in the past. These new requirements document the certification requirements previously applied to certified refrigeration line sets and apply to line sets made of copper or steel. Line sets made of materials other than copper or steel, including nonmetallic materials, are outside the scope of these new requirements. Revising “model codes” would likely be necessary before requirements covering materials other than copper or steel could be included within UL 207.
Refrigeration fittings — Refrigeration fittings certified in the past using applicable requirements from UL 109, the Standard for Safety for Tube Fittings for Flammable and Combustible Fluids, Refrigeration Service, and Marine Use, together with requirements from UL 207. The revisions recently made to UL 207 incorporate fitting requirements, including those from UL 109, into UL 207. However, the legacy option of certifying refrigeration fittings using requirements from UL 109 together with those in UL 207 continues to be permitted. In addition, refrigeration fittings complying with ISO 14903, regarding refrigerating systems and heat pumps – qualification of tightness of components and joints, are also now being permitted as an additional option.
Nonmetallic materials — A refrigerant-containing component, such as a refrigeration line set, may be provided with a nonmetallic material, such as thermal insulation. In anticipating the use of refrigerant-containing components — particularly insulated line sets — within a plenum or duct, nonmetallic materials provided as part of a refrigerant containing component are now being required to either have a flame spread/smoke developed rating of 25/50, based on UL 723, the Standard for Test for Surface Burning Characteristics of Building Materials, or will be limited in surface area to no more than 10 ft2 (0.93 m2). Nonmetallic materials not complying with UL 723 and having a surface area limited to 10 ft2 (0.93 m2) will be required to comply with a 5VA flame rating in accordance with UL 94, the Standard for Tests for Flammability of Plastic Materials for Parts and Devices and Appliances. As an alternate, such material could instead comply with the 127 mm end-product flame test specified in UL 746C, the Standard for Polymeric Materials – Use in Electrical Equipment Evaluations.
If a nonmetallic material does not comply with UL 723, the Standard for Test for Surface Burning Characteristics of Building Materials, but instead complies with either the 5VA rating of UL 94 or the 127 mm test of UL 746C, then a marking on the nonmetallic material is required to specify that the nonmetallic material “ … may not be suitable for installation within plenums or ducts.” Such a marking is intended to prompt the end-user of a refrigerant-containing component to determine the suitability of the nonmetallic materials based on a specific end-use application. Some end-use applications may only permit nonmetallic materials complying with the UL 723 flame spread/smoke developed 25/50 rating.
These nonmetallic materials requirements align with similar requirements in other standards that anticipate the use of nonmetallic materials within a plenum or duct. Since these new requirements to UL 207 are expected to have only minimal or no impact on previously certified products, they became effective on the publication date of Jan. 21, 2020.