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California Energy Commission MEF CEF Lookup Reference

Reference Compliance Updated Jul 24, 2026 ยท Appliance Repair

Why this matters

California Energy Commission (CEC) regulates the energy efficiency of clothes washers, dishwashers, refrigerators, freezers, room air conditioners, and other appliances sold in California under the Appliance Efficiency Regulations (Title 20, California Code of Regulations, Sections 1601 through 1608). Replacing an appliance with a model that is not listed in the CEC MAEDBS (Modernized Appliance Efficiency Database System) is a regulatory violation by the seller, and California rebate programs (TECH Clean California, PG&E, SoCalGas, SDG&E, LADWP) will reject any rebate claim against an unlisted model. Knowing how to look up the MEF, CEF, IMEF, IWF, and AHAM ratings before quoting saves the customer rejection and the contractor a credit issue.

What MEF, CEF, IMEF, and IWF mean

These are the four efficiency metrics most often referenced on California rebate applications and Title 20 listings:

  • MEF (Modified Energy Factor): clothes washer metric replaced by IMEF in 2018 DOE test procedure. Cubic feet of laundry processed per kWh of energy used per cycle. Higher is better. Legacy listings still use MEF.
  • IMEF (Integrated Modified Energy Factor): 2018-and-later clothes washer metric. Includes standby and off-mode energy in addition to active cycle energy. Higher is better.
  • CEF (Combined Energy Factor): clothes dryer metric. Pounds of laundry dried per kWh including standby. Higher is better. Mandatory current metric for all clothes dryers.
  • IWF (Integrated Water Factor): clothes washer water metric. Gallons of water per cycle per cubic foot of laundry capacity. Lower is better.
  • AHAM Cubic Feet: refrigerator capacity metric per AHAM Standard HRF-1.

Where to look up a model

Two authoritative sources:

  1. CEC MAEDBS (Modernized Appliance Efficiency Database System): appliances.energy.ca.gov. Search by manufacturer and model. Returns the certified efficiency values, the certification date, and the regulated category.
  2. DOE Compliance Certification Database (CCD): regulations.doe.gov/certification-data. National-level certifications; broader than CEC but used for federal Energy Star verification.

A model that does not appear in MAEDBS cannot legally be sold or installed in California for the regulated category. Verify before promising the customer a rebate.

Minimum efficiency standards under Title 20 (as of 2024)

These are the minimum legal sale standards in California for the most common appliances:

  • Clothes washer (residential, top-load): IMEF 1.57 minimum, IWF 6.5 maximum
  • Clothes washer (residential, front-load): IMEF 1.84 minimum, IWF 4.7 maximum
  • Clothes dryer (residential, electric, standard): CEF 3.73 minimum
  • Clothes dryer (residential, electric, compact 240 V): CEF 3.61 minimum
  • Clothes dryer (residential, gas, standard): CEF 3.30 minimum
  • Dishwasher (residential, standard): 270 kWh per year maximum, 3.5 gallons per cycle maximum
  • Dishwasher (residential, compact): 203 kWh per year maximum, 3.1 gallons per cycle maximum
  • Refrigerator-freezer (top-mount, automatic defrost): 5.4 percent reduction below DOE 2014 baseline (formula-based, depends on AHAM volume)

These are minimums. Energy Star tier and CEC Tier 1 / Tier 2 lists carry tighter values used by some utility rebate programs.

Reading the CEC listing for a clothes washer

A typical MAEDBS clothes washer record returns:

  • Manufacturer
  • Brand
  • Basic Model Number
  • IMEF (cu ft / kWh / cycle)
  • IWF (gallons / cycle / cu ft)
  • Cubic foot tub volume
  • Certification date
  • Compliance Type (Energy or Water or both)

A replacement washer in a California home should have IMEF at least equal to or greater than the unit being removed for the customer to see an energy savings. Many rebate programs require IMEF 2.06 or higher for a tier-eligible rebate.

Reading the CEC listing for a refrigerator

Refrigerator listings include:

  • AHAM adjusted volume (cu ft)
  • Annual energy use (kWh per year)
  • Configuration (top-mount, bottom-mount, side-by-side, French-door, single-door)
  • Defrost type (manual, partial automatic, automatic)
  • Through-the-door ice and water (yes/no, which affects baseline)
  • Certification date

For Energy Star comparison, the federal baseline is 10 percent more efficient than DOE minimum; the Energy Star Most Efficient list adds further criteria.

When the model number on the appliance does not match MAEDBS

This happens often on basic-model number variations (the model on the nameplate has a regional or color suffix that the basic model number listed in MAEDBS does not):

  • Strip trailing suffixes after the dash or slash
  • Search by basic model number only (the first 6 to 10 characters typically)
  • If still no result, manufacturer customer service can provide the basic model number used for federal certification

For example, Whirlpool model WTW7120HW0 on the nameplate corresponds to basic model WTW7120HW in MAEDBS. The trailing 0 is a production revision indicator and not part of the certified basic model.

Title 20 enforcement and contractor exposure

Title 20 enforcement falls primarily on the seller (the retailer or distributor) and the manufacturer, not the installation contractor. However:

  • A contractor who supplies the appliance as part of the installation is acting as the seller under Title 20
  • The CEC may issue notices of violation under Public Resources Code Section 25402(c) with civil penalties
  • Rebate fraud (claiming a rebate on an unlisted model) carries program-specific clawback provisions

When the appliance is customer-supplied, document in writing that the customer supplied the equipment and retain that record for at least three years.

Quick lookup workflow

For a customer call where rebate eligibility matters:

  1. Get the exact nameplate model number from the customer
  2. Search MAEDBS at appliances.energy.ca.gov
  3. Verify the relevant metric meets or exceeds the rebate program threshold
  4. Print the MAEDBS record and attach to the work order
  5. After installation, photograph the nameplate of the installed unit and include with the rebate submittal

Do not rely on Energy Star labels alone as proof of California Title 20 compliance. Energy Star is a federal voluntary program; Title 20 is California regulatory minimum. A model can be Energy Star certified federally but absent from MAEDBS if the manufacturer did not file the California certification.

References

  • California Code of Regulations Title 20, Sections 1601-1608 (Appliance Efficiency Regulations)
  • California Energy Commission Modernized Appliance Efficiency Database System (MAEDBS)
  • 10 CFR Part 430 Energy Conservation Program for Consumer Products
  • AHAM Standard HRF-1-2019 Energy and Internal Volume of Refrigerating Appliances
  • California Public Resources Code Section 25402

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