Is a heat pump worth it in La Mesa?

This one's marginal in La Mesa: it only clears if you stay long enough. Against a like-for-like gas furnace and AC swap, going electric costs $1,000 more up front here (already netting out a $2,000 tax credit). That premium is recovered through $103 of lower running costs every year, landing the payback clock at roughly 9.7 years. It's a genuine toss-up here — La Mesa's numbers don't point clearly either way.

La Mesa's weather, in the numbers that matter

Degree days tell the story here: La Mesa racks up 1807 heating degree days each year (base 65°F), and summers are hot enough that cooling matters as much as heating, with 1027 cooling degree days on the cooling side. The 99% winter design temperature here — the cold snap equipment must be sized for, not the seasonal average — is 35.6°F, against a record low of 32°F. That puts the seasonal coefficient of performance at 3.26 for the recommended standard unit. La Mesa's winters don't get cold enough to need the cold-climate premium — a standard unit holds up fine. These numbers come from GILLESPIE FIELD AIRPORT, the closest NOAA station, 4.8 miles out.

What it actually costs to run, year to year

Modelled on a typical 2000-square-foot house, the heat pump draws about 1,404 kWh a year to keep it warm, plus cooling, for a combined electric bill near $748 a year. That compares with roughly 19 Mcf a year of gas at La Mesa's 22.01 per-Mcf rate — about $851 a year — against a local electricity rate of 32.83¢/kWh. Priced as a standalone purchase rather than against a like-for-like replacement, equipment payback runs about 106.9 years, for a 15-year net position $544 ahead.

The other scenario: no gas furnace to begin with

Gas isn't universal in La Mesa — many houses run on electric heat already. Compared with baseboard or electric-furnace resistance heat, the numbers shift in the heat pump’s favor. Switching saves about $1,191 a year here — a heat pump moving heat rather than generating it needs far less electricity than resistance coils — so the extra $5,500 spent up front comes back in about 4.6 years.

How La Mesa compares nationally

Ranked against the other 3206 cities covered, La Mesa comes in at 2537 for heating severity — 1 would be the coldest place in the dataset — and 657 by population, where 1 is largest. That's the mildest third of cities covered, where utility rates carry more of the answer than climate does.

Deciding what's next in La Mesa, CA

La Mesa, California is home to about 60,767 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. In La Mesa, nothing is lost by holding off until the current equipment genuinely fails.

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 3.26 seasonal COP, the degree-day corrections, the equipment costs — is documented in the methodology guide. Homes in La Mesa without gas service should read the electric-resistance comparison instead — the numbers there differ from the gas case above.