California: heat-pump-ready circuit at gas furnaces

What the code requires

The 2025 California Electrical Code adds section 440.3, which points to California Energy Code §150.0(t). It applies to each dwelling unit in new buildings with one or two dwellings when a gas or propane furnace serves the home. Other gas equipment does not trigger it.

The home needs a dedicated 240-volt branch circuit within 3 ft of the furnace, accessible with no obstructions, with conductors rated 30 A minimum. It ends at a blank cover identified as 240V ready. The main service panel needs a reserved double-pole breaker space permanently marked For Future 240V use.

No receptacle or breaker has to be installed at construction, and the circuit may not serve other appliances. All components must meet the California Electrical Code.

On the job

• A cover without the 240V ready identification, or a panel space without the For Future 240V use marking, does not comply.
• A circuit that ends more than 3 ft from the furnace does not comply.
• The reserved space takes up a breaker position in the main panel; see 408.2 for how the reserved spaces add up in a new home.

Exceptions that matter

• Applies only to newly constructed buildings. Additions and alterations are not covered.
• Not required when electric or heat pump space heating is installed.
• Applies to permit applications filed on or after Jan 1, 2026.

In California

For multifamily buildings, the 2025 Energy Code places the same 240-volt, 30-amp, 3 ft rule in §160.9(b), while the CEC text still cites an older subsection letter, so confirm with your building department.

Related sections

• NEC 422.3: California: electric-ready water heater, cooktop, dryer
• NEC 408.2: California: reserved breaker spaces in new homes
• NEC 706.10: California battery-ready rules for new homes
• NEC 440.14: Air-conditioner disconnect location

Where this comes from

• California Energy Commission: 2025 Building Energy Efficiency Standards
• California Energy Commission: 2025 Single-Family Residential Compliance Manual, ch. 10
• California Energy Commission: 2022 Single-Family Residential Compliance Manual, ch. 10
• California Energy Commission: 2025 Building Energy Efficiency Standards page
• Read the official NEC free at NFPA