Heat pump vs. gas furnace in Warrenville, IL
Warrenville is a place where a heat pump genuinely costs more to operate than the alternative. Against a like-for-like gas furnace and AC swap, going electric costs $3,500 more up front here (already netting out a $2,000 tax credit). Unfortunately the electric bill outweighs the gas bill it replaces by about $295 a year here, so the extra spend stays unrecovered. That's Warrenville's own climate and rates talking, not a hedge or a caveat.
How cold Warrenville actually gets
Warrenville has a cold winter that leans hard on heating equipment — 5064 heating degree days a year against a 65°F base — and summers add a moderate cooling load, at 915 cooling degree days. Sizing runs off the design temperature, not the average day: -7.1°F here (record low -14.1°F), which works out to a seasonal COP of 2.53 for the cold-climate class of unit this climate calls for. Warrenville 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 DUPAGE AIRPORT, 7.1 miles from Warrenville — the closest one on record.
The month-to-month numbers for Warrenville
Modelled on a typical 2000-square-foot house, the heat pump draws about 5,068 kWh a year to keep it warm, plus cooling, for a combined electric bill near $1,115 a year. The gas furnace it replaces burns roughly 53 Mcf a year at 11.25 per Mcf here, for a running cost near $819 a year (electricity here runs 19.06¢/kWh). Looked at as a full purchase rather than an incremental one, payback here is longer than the 15-year equipment life, leaving the 15-year total $7,930 behind.
Electric resistance heat in Warrenville, compared
Plenty of homes in Warrenville heat with electricity alone, no gas line involved. Against electric-resistance heat — baseboard or an electric furnace, both 100% efficient but still just resistance — the case for switching gets stronger here. Switching saves about $1,555 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 5.1 years.
Warrenville against the rest of the country
Ranked against the other 3206 cities covered, Warrenville comes in at 641 for heating severity — 1 would be the coldest place in the dataset — and 2369 by population, where 1 is largest. That's the coldest third of the dataset, where climate does most of the work behind this figure.
What to do with this number in Warrenville
Warrenville, Illinois is home to about 15,247 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 Warrenville, nothing is lost by holding off until the current equipment genuinely fails.
Line up a few local HVAC quotes before you decide.
More on how this number was built
Every constant behind this page — the 2.53 seasonal COP, the degree-day corrections, the equipment costs — is documented in the methodology guide. Warrenville's -7.1°F design temperature is below the 25°F line, which is why a cold-climate unit is the right call here — see what that changes in the cold-climate unit guide.