Should Kennesaw switch to a heat pump?

This one's marginal in Kennesaw: it only clears if you stay long enough. Swap a failed furnace and AC for a heat pump rather than buying like-for-like, and the extra cost here runs $3,500 after a $2,000 federal tax credit. Kennesaw's residents would see roughly $374 a year back in running costs, putting the payback around 9.3 years. It's a genuine toss-up here — Kennesaw's numbers don't point clearly either way.

How cold Kennesaw actually gets

2508 heating degree days pile up here every year, so Kennesaw has a mild winter by US standards; the cooling side runs to 2112 cooling degree days, where summers are hot enough that cooling matters as much as heating. 19.4°F is the figure equipment gets sized against here — the 99th-percentile cold snap, not an average day — with a record low of 10°F on file. Worked through the model, that's a seasonal COP of 3.17 on the cold-climate unit fit for this climate. Kennesaw needs the cold-climate class of unit: past a 25°F design temperature a standard heat pump falls back on resistance backup often enough to eat the savings. Source: NOAA station COBB CO-MC COLLUM FLD ARPT, 1.4 miles from Kennesaw — the closest one on record.

The month-to-month numbers for Kennesaw

Electricity use for heating alone comes out to about 2,003 kWh a year on the 2000-square-foot reference house; folding in cooling puts the electric bill near $567 a year. Kennesaw's gas rate of 20.42 per Mcf, applied to the 26 Mcf a year the furnace burns, puts its running cost near $941 a year, against 14.90¢ per kWh for electricity. Priced as a standalone purchase rather than against a like-for-like replacement, equipment payback runs about 36.1 years, for a 15-year net position $2,116 ahead.

Electric resistance heat in Kennesaw, compared

Not every home in Kennesaw has gas service. Compared with baseboard or electric-furnace resistance heat, the numbers shift in the heat pump’s favor. Switching saves about $787 a year here — a heat pump moving heat rather than generating it needs far less electricity than resistance coils — so the extra $8,000 spent up front comes back in about 10.2 years.

Kennesaw against the rest of the country

Among 3206 cities, Kennesaw's winter puts it at rank 2178 for severity, while its size puts it at rank 1102 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 Kennesaw, GA

Kennesaw, Georgia is home to about 37,740 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 Kennesaw, nothing is lost by holding off until the current equipment genuinely fails.

Get quotes from local HVAC contractors before deciding.

Reading further on this page's numbers

Every constant behind this page — the 3.17 seasonal COP, the degree-day corrections, the equipment costs — is documented in the methodology guide. Kennesaw's 19.4°F design temperature falls on the cold side of the 25°F cutoff the cold-climate unit guide walks through.