Going Electric Starts at the Panel
Heat pumps, mini-splits and heat pump water heaters each need a dedicated 240V circuit, often 20 to 60 amps depending on the size of the system. In an older LA home on 100 amp service, adding one alongside an EV charger or electric range can push the panel past its limit.
A load calculation tells you where you stand. Sometimes the new system fits. Sometimes a sub-panel or service upgrade is needed. We’ll tell you before the HVAC work starts.
Check for rebates. LADWP, Southern California Edison and other local utilities have offered heat pump programs at different times. Programs change, so check your utility’s current offer.
The nameplate sets the circuit. Every outdoor unit lists a minimum circuit ampacity and a maximum overcurrent protection on its label. The wire is sized from the first number, and the breaker can’t exceed the second. A breaker larger than the label allows is a code violation the inspector will flag.
The disconnect goes within sight of the unit. Code requires a way to shut off power at the outdoor condenser or heat pump, so a technician can work on it safely. Code also calls for a service receptacle near the equipment so whoever maintains it has power for tools and diagnostics.
Mini-splits have their own wiring layout. A ductless system runs a line set and a communication cable between the outdoor unit and each indoor head. Some models power the heads from the outdoor unit, others need separate circuits. We wire to the manufacturer’s diagram so the HVAC crew can set the equipment and start it up.
A replacement unit can change the wiring. A new condenser may draw a different load than the one it replaces, and the old disconnect or whip may be undersized, corroded or no longer allowed. Checking what is there before you buy keeps the equipment choice and the electrical plan lined up.
