California: electric-ready water heater, cooktop, dryer

What the code requires

Water heater, §150.0(n): when a gas or propane water heater serves the home, a space at least 2.5 ft by 2.5 ft and 7 ft tall must be set aside for a future heat pump water heater, with a condensate drain no more than 2 in. above the heater base that drains by gravity.

If that space is within 3 ft of the water heater, a dedicated 125-volt, 20-amp receptacle goes within 3 ft, unobstructed, fed by a 120/240-volt, 3-conductor circuit rated 30 A minimum. The unused conductor is labeled spare and isolated at both ends, and a reserved single-pole space next to that breaker is labeled Future 240V Use.

If the space is more than 3 ft away, a dedicated 240-volt circuit rated 30 A minimum goes within 3 ft of the space with a blank cover labeled 240V ready, plus a reserved double-pole space marked For Future 240V use. The hot water pipe from the gas heater must run through the space first, the cold supply must pass through it or be a dedicated supply there, and that piping must be exposed and readily accessible.

Cooktop, §150.0(u): a gas or propane cooktop, including a gas range, triggers a 240-volt circuit within 3 ft with conductors rated 50 A minimum, a 240V ready cover and a reserved double-pole space. A stand-alone gas oven does not trigger it. Dryer, §150.0(v): a dryer location with gas or propane piping needs a 240-volt circuit within 3 ft rated 30 A minimum, a 240V ready cover and a reserved double-pole space.

On the job

• A spare conductor on the water heater circuit that is not labeled and isolated at both ends does not comply.
• Leaving out the reserved single-pole space next to the water heater breaker does not comply.
• A cooktop-ready circuit sized under 50 A does not comply.
• An installed 240-volt dryer receptacle rated 30 A or more, together with a gas stub-out, satisfies the dryer requirement.

Exceptions that matter

• New construction only, for permit applications filed on or after Jan 1, 2026.
• Not required when the electric or heat pump appliance is installed, including a 120-volt heat pump water heater.

In California

The 2025 Energy Code dropped the earlier 10 AWG copper wording, so the water heater circuit is now specified as rated 30 A minimum. For multifamily buildings, CEC 422.3(B) cites §160.9(b) and (c) for cooktops and dryers, but the 2025 Energy Code puts them at §160.9(c) and (d), so confirm with your building department.

Related sections

• NEC 440.3: California: heat-pump-ready circuit at gas furnaces
• NEC 408.2: California: reserved breaker spaces in new homes
• NEC 210.8(D): GFCI for dishwashers, ranges, dryers and other appliances
• NEC 422.5: GFCI protection for appliances

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