Electrical Controls for Use in Refrigeration and Air-Conditioning Equipment Employing Flammable Refrigerants

Electrical controls intended for residential and commercial refrigeration applications are usually certified according to the IEC/UL/EN 60730 Standard series. When the electronic control is intended to be integrated into the HVAC/R application, they are also evaluated along with applicable requirements of IEC/UL/EN 60335-1 and applicable Part 2-x based on the specific appliance type.

Due to the change in global sustainability regulations like the reduction of greenhouse gas emissions outlined by EU F-Gas Regulation 517/2014, the market nowadays requires more green refrigerant gases, which are unfortunately more flammable than previous ones.

As a result, product standards that cover residential and commercial refrigeration applications have been updated to evaluate the compliance of products involving flammable refrigerant gases.

Such new requirements affect electrical control manufacturers as well. Companies that make electronic controls intended to be integrated into refrigeration applications are strongly encouraged by the market to be already in compliance with flammable refrigerant requirements coming for the latest editions of IEC/UL/EN 60335-2-24, IEC/UL/EN 60335-2-2-40 and IEC/UL/EN 60335-2-89.

How does the new standard assist manufacturers during their design, development, and certification processes?

Latest editions of IEC/UL/EN 60335-2-24, IEC/UL/EN 60335-2-2-40 and IEC/UL/EN 60335-2-89 state that appliances shall be constructed so that any leaked refrigerant will not flow or stagnate to cause a fire or explosion hazard in areas within the appliance where electrical components that could be a source of ignition and could function under normal or abnormal conditions are fitted.

Flammable gas requirements applicable to electrical controls can be summarized as:

• Evaluation of spark ignition components.
• Determination of arcs and hot surfaces during normal and abnormal conditions. Tests under normal and abnormal conditions must prove the product cannot reach the self-ignition temperature of the flammable gas employed in the end application. Failure modes and effects analysis (FMEA) must demonstrate that no electronic fault can generate an arc capable of reaching the gas’s self-ignition temperature.

At present, UL Solutions certifies electrical controls intended for residential and commercial refrigeration applications that comply with two standards:

• IEC/UL/EN 60730-1, the Standard for Automatic Electrical Controls - Part 1: General Requirements
• IEC/UL/EN 60730-2-9, the Standard for Automatic Electrical Controls - Part 2-9: Particular Requirements for Temperature Sensing Controls

When an electronic control is integrated into a refrigeration application that includes flammable gases, UL Solutions also assesses the flammable gas requirements that apply to the electrical controls based on the latest editions of one or more of three standards:

• IEC/UL/EN 60335-2-24, the Standard of Household and Similar Electrical Appliances - Safety - Part 2-24: Particular Requirements for Refrigerating Appliances, Ice-Cream Appliances and Ice-Makers
• IEC/UL/EN 60335-2-89, the Standard of Household and Similar Electrical Appliances - Safety - Part 2-89: Particular Requirements for Commercial Refrigerating Appliances and Ice-Makers with an Incorporated or Remote Refrigerant Unit or Motor-Compressor
• IEC/EN/UL 60335-2-40, the Standard of Household and Similar Electrical Appliances - Safety - Part 2-40: Particular Requirements for Electrical Heat Pumps, Air-Conditioners and Dehumidifiers

Our expert, Davide Nardo, UL Solutions HVAC Senior Product/Service Specialist, states, “We currently provide bundled services thanks to the harmonization of IEC/UL/EN 60335 with the standards of many other countries (the U.S., Canada, the EU, etc.). At UL Solutions, we provide an evaluation of applicable end-product requirements. Usually, requirements are based on IEC 60335-1 and the applicable Part -2-x related to the specific appliance type (i.e., IEC/UL/EN 60335-2-40 for heat pumps).”

We can help customers comply with the flammable gas requirements that apply to their electrical controls in three ways:

• By providing training on the relationships between flammable refrigerants and electrical controls as addressed by the requirements of IEC/UL/EN 60335-2-24, IEC/UL/EN 60335-2-2-40 and IEC/UL/EN 60335-2-89.
• By conducting advisory meetings and/or gap analysis related to the concepts/prototypes that underlie the requirements for flammable refrigerants in IEC/UL/EN 60335-2-24, IEC/UL/EN 60335-2-2-40 and IEC/UL/EN 60335-2-89.
• By offering assessment and certification based on the IEC/UL/EN 60730 Standard series and the applicable requirements for flammable A2L or A3 refrigerant in IEC/UL/EN 60335-2-24, IEC/UL/EN 60335-2-2-40 and IEC/UL/EN 60335-2-89.

Which products are most affected by the flammable refrigerant requirements of IEC/UL/EN 60335-2-24 and IEC/UL/EN 60335-2-2-40 are applicable?

“Generally speaking, all electrical controls which are incorporated into appliances using flammable A2L or A3 refrigerant and covered by the HVAC segment." Davide Nardo replies.

Why UL Solutions?

“Because UL Solutions provides our customers with a global network of laboratories and engineering experts to help with their testing and certification needs. We offer safety certification for appliance controls and other adjunct services.” – he continues – “Our technical experts hold leadership roles on IEC technical committees TC 72, TC 61 and TC61C, which are responsible for developing the requirements in IEC 60730-x, IEC 60335-1, IEC 60335-2-24, IEC 60335-2-2-40 and IEC 60335-2-89.

We are a global leader in applied safety science. UL Solutions delivers testing, inspection and certification services, together with software products and advisory offerings, that support our customers’ product innovation and business growth.”

Our services include:

• Professional product safety certification services to access the North American market.
• Global market access solutions with IEC/UL/EN 60730-1 harmonized Standards, including evaluation and assessment, IEC/UL/EN 60335, and applicable Part 2-x based on the specific appliance type.
• Early engagement with standards training, advisory and gap analysis, which helps reduce your product development cycle.
• IECEE CB Scheme’s Customer Testing Facility (CTF) program and UL’s Data Acceptance Program (DAP), which offer flexible solutions and enable manufacturers that qualify and follow requirements to test products at their in-house laboratories.

UL certification of electrical control certified according to IEC/EN/UL 60730 plus IEC/UL/EN 60335 flammable gas requirements will facilitate the acceptance of this component made during the final assessment of the complete HVAC/R machine.