Whittier, CA: the heat pump payback math
A heat pump earns back its extra cost in Whittier within a sensible timeframe. $1,000 is what Whittier would pay extra to go electric rather than replace the furnace and AC with the same again, once the $2,000 federal credit is applied. That premium is recovered through $125 of lower running costs every year, landing the payback clock at roughly 8 years. The window here is reasonable, and it's specific to what Whittier actually pays for power and gas.
Whittier's weather, in the numbers that matter
1315 heating degree days pile up here every year, so Whittier barely has a winter to speak of; the cooling side runs to 1024 cooling degree days, where summers are hot enough that cooling matters as much as heating. Sizing runs off the design temperature, not the average day: 39°F here (record low 35.1°F), which works out to a seasonal COP of 3.36 for the standard class of unit this climate calls for. Whittier's winters don't get cold enough to need the cold-climate premium — a standard unit holds up fine. Climate figures trace to the nearest NOAA station, FULLERTON MUNICIPAL ARPT, 7 miles from Whittier.
The month-to-month numbers for Whittier
A 2000-square-foot house here would pull roughly 991 heating kilowatt-hours annually on top of cooling, totalling about $612 a year on electricity. Whittier's gas rate of 22.01 per Mcf, applied to the 14 Mcf a year the furnace burns, puts its running cost near $737 a year, against 32.83¢ per kWh for electricity. Looked at as a full purchase rather than an incremental one, payback here is roughly 87.9 years, leaving the 15-year total $877 ahead.
If your home heats with electric baseboard instead of gas
Plenty of homes in Whittier heat with electricity alone, no gas line involved. Swap the comparison to resistance heat instead of gas, and Whittier's answer improves. About $917 a year comes back this way, enough that the 6-year payback clears the $5,500 premium comfortably within the equipment's life.
Whittier against the rest of the country
Among 3206 cities, Whittier's winter puts it at rank 2753 for severity, while its size puts it at rank 424 for population — 1 in both cases being the extreme. That's the mildest third of cities covered, where utility rates carry more of the answer than climate does.
Deciding what's next in Whittier, CA
Whittier, California is home to about 85,589 people, and the figures above are the same ones a local HVAC contractor uses to size and quote a system — this site doesn't guess where a real quote would land, it just tells you whether it's worth asking for one. Given the math above, Whittier is a place worth lining up quotes ahead of a breakdown, not waiting for one.
Ask a local HVAC contractor for a quote before committing either way.
Reading further on this page's numbers
Every constant behind this page — the 3.36 seasonal COP, the degree-day corrections, the equipment costs — is documented in the methodology guide. The $2,000 federal credit baked into Whittier's number is explained, with the before-and-after math, in the tax credit guide.