DEPARTMENT OF COMMERCE

[Filed February 17, 2026, 10:09 a.m., effective March 20, 2026]

Effective Date of Rule: Thirty-one days after filing.

Purpose: RCW 19.260.080 (1)(b) maintains that the department of commerce (commerce) may adopt by rule a more recent version of the interface standard and application layer requirements for electric storage water heaters. Commerce is proposing to update state standards for electric storage water heaters to reflect more recent versions of the ANSI/CTA-2045-A standards listed in WAC 194-24-180 in order to maintain and improve consistency with the most up-to-date version of the standard and with comparable standards in other states.

Citation of Rules Affected by this Order: Amending WAC 194-24-180(2).

Statutory Authority for Adoption: RCW 19.260.080 (1)(b).

Adopted under notice filed as WSR 25-24-090 on December 2, 2025.

Number of Sections Adopted in Order to Comply with Federal Statute: New 0, Amended 0, Repealed 0; Federal Rules or Standards: New 0, Amended 0, Repealed 0; or Recently Enacted State Statutes: New 0, Amended 0, Repealed 0.

Number of Sections Adopted at the Request of a Nongovernmental Entity: New 0, Amended 0, Repealed 0.

Number of Sections Adopted on the Agency's own Initiative: New 0, Amended 1, Repealed 0.

Number of Sections Adopted in Order to Clarify, Streamline, or Reform Agency Procedures: New 0, Amended 0, Repealed 0.

Number of Sections Adopted using Negotiated Rule Making: New 0, Amended 0, Repealed 0; Pilot Rule Making: New 0, Amended 0, Repealed 0; or Other Alternative Rule Making: New 0, Amended 0, Repealed 0.

Date Adopted: February 17, 2026.

AMENDATORY SECTION(Amending WSR 22-20-025, filed 9/23/22, effective 10/24/22)

WAC 194-24-180Electric storage water heaters.

(1) Scope. This rule applies to new electric storage water heaters manufactured on or after January 1, 2023.

(2) Standard. Electric storage water heaters must have a modular demand response communications port compliant with:

(a) The March 2018 version of the ANSI/CTA–2045-A communication interface standard, the February 2021 version of the ANSI/CTA-2045-B application layer requirements, or a standard determined by the department to be equivalent; and

(b) The March 2018 version of the ANSI/CTA-2045-A application layer requirements, or the February 2021 version of the ANSI/CTA-2045-B communication interface standard.

The interface standard and application layer requirements required in this subsection are the versions established in March 2018 and February 2021.

(3) Upon written request by a manufacturer, the department will determine whether an alternative communications port and communication interface standard are equivalent for the purposes of subsection (2) of this section.

(a) Any requested alternative must use a standard that is open and widely available and must provide the demand response functions provided using the standards identified in subsection (2) of this section.

(b) A request for designation of a standard must provide technical documentation demonstrating that the standard satisfies the requirements in (a) of this subsection and must describe any industry or stakeholder process used in developing the standard. The department will provide reasonable opportunity for input by utilities, manufacturers, technical experts and other interested stakeholders prior to determining whether the proposed standard is equivalent. The department will make available on a publicly accessible website any standard that it determines to be equivalent.

(4) Testing. There is no test method required for this product.

(5) Listing. There is no listing requirement for this product.

(6) Marking. Every unit of every electric storage water heater must have a label or marking indicating compliance with the standard in this section. The format and content of the label or marking must be approved in advance by the department.