What size AC for Evansville, IN? 3 tons for 2,000 sq ft

What size AC a 2,000 sq ft house in Evansville needs

3 tons central AC or heat pump, about 35,100 BTU/hr of load

The 20 BTU per square foot chart would put in 3.5 tons, about 20% more than this climate needs. An oversized unit cools the air fast, shuts off before it pulls moisture out, and leaves the house cold and clammy.

If a contractor quotes you more than 3 tons for an average 2,000 sq ft house here, ask to see the Manual J load calculation behind it before you sign. That works out to one ton per 683 square feet in this climate. For a single room, size by the room: 17.6 BTU/hr per square foot.

The climate it is sized for

Climate from NOAA's 1991 to 2020 normals at Evansville Regional Airport (4.5 mi away). Jul is the hottest month, averaging a high of 88.6°F and a low of 68.8°F, with about 41 days a year at 90°F or more. That gives a design temperature of 94°F against 75°F inside.

What it costs to run

About 2,248 kWh a year at SEER2 14.3, or roughly $383 at Indiana's average residential rate of 17.04¢ per kWh. Cooling runs 5 months of the year here.

What drives the load in Evansville

Of the 35,100 BTU/hr, 13,680 comes through walls, roof and windows on a 94°F afternoon (39%), 13,000 is sun on the house (37%), 2,120 is four people and their appliances, and 6,300 is moisture the coil has to wring out of Evansville's summer air (18%).

Heat through the shell is the biggest share here, so insulation and air sealing cut the size you need more than shading would. Sensible heat totals 28,800 BTU/hr before the moisture allowance.

Other house sizes in Evansville

Single rooms with a window or mini-split unit: a 150 sq ft bedroom needs about 2,600 BTU/hr; a 350 sq ft living room needs about 6,200 BTU/hr; a 600 sq ft open plan kitchen and family room needs about 10,600 BTU/hr.

Month by month in Evansville

Jul alone uses 28% of the year's cooling energy. The unit runs the equivalent of 915 hours a year at full output.

Evansville against nearby cities

Of 88 Indiana cities here, Evansville has the 2nd highest cooling load. The range runs from Auburn at 24,100 BTU/hr to Jasper at 36,400.

Where Evansville's weather numbers come from

The nearest NOAA station with full 1991 to 2020 normals is Evansville Regional Airport, 4.5 miles from the center of Evansville at 402 ft above sea level. That is close enough that the station's summers are Evansville's summers.

2 other cities use the same station and get the same climate inputs. The closest to Evansville: Henderson (11 mi away, 15.1 mi from the station), Owensboro (28 mi away, 29.7 mi from the station). Evansville sits closer to the station than any of them, so its numbers are the best measured of the group.

The sun over Evansville in late July

At 37.99°N, the noon sun on 21 July stands 72.4° above the horizon over Evansville and the day runs 14 h 15 min from sunrise to sunset. A lower noon sun puts more of the day's heat on east and west walls than on the roof, which is why shading west glass pays off here. Shorter days give the house a longer night to shed the day's heat.

115,395 people live in Evansville, the 3rd largest of the 88 Indiana cities sized on this site. Coordinates used: 37.9877, -87.5347.

Evansville AC sizing questions