What size AC for Kearney, NE? 2.5 tons for 2,000 sq ft

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

2.5 tons central AC or heat pump, about 29,500 BTU/hr of load

The 20 BTU per square foot chart would put in 3.5 tons, about 42% 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 2.5 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 812 square feet in this climate. For a single room, size by the room: 14.8 BTU/hr per square foot.

The climate it is sized for

Climate from NOAA's 1991 to 2020 normals at Kearney 4 Ne (4 mi away). Jul is the hottest month, averaging a high of 86.6°F and a low of 63°F, with about 31 days a year at 90°F or more. That gives a design temperature of 92°F against 75°F inside.

What it costs to run

About 1,180 kWh a year at SEER2 14.3, or roughly $152 at Nebraska's average residential rate of 12.92¢ per kWh. Cooling runs 4 months of the year here.

What drives the load in Kearney

Of the 29,500 BTU/hr, 12,240 comes through walls, roof and windows on a 92°F afternoon (41%), 13,000 is sun on the house (44%), 2,120 is four people and their appliances, and 2,200 is moisture the coil has to wring out of Kearney's summer air (7%).

Sun is the biggest share here, more than heat through the walls, so shading west windows and a light roof cut the size you need more than extra insulation would. Sensible heat totals 27,360 BTU/hr before the moisture allowance.

Other house sizes in Kearney

Single rooms with a window or mini-split unit: a 150 sq ft bedroom needs about 2,200 BTU/hr; a 350 sq ft living room needs about 5,200 BTU/hr; a 600 sq ft open plan kitchen and family room needs about 8,900 BTU/hr.

Month by month in Kearney

Jul alone uses 34% of the year's cooling energy. The unit runs the equivalent of 571 hours a year at full output.

Kearney against nearby cities

Of 16 Nebraska cities here, Kearney has the 14th highest cooling load. The range runs from South Sioux City at 28,000 BTU/hr to Bellevue at 34,300.

Where Kearney's weather numbers come from

The nearest NOAA station with full 1991 to 2020 normals is Kearney 4 Ne, 4 miles from the center of Kearney at 2,130 ft above sea level. That is close enough that the station's summers are Kearney's summers.

No other city in this set uses Kearney 4 Ne, so this sizing is Kearney's alone.

The sun over Kearney in late July

At 40.70°N, the noon sun on 21 July stands 69.7° above the horizon over Kearney and the day runs 14 h 29 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.

34,741 people live in Kearney, the 5th largest of the 16 Nebraska cities sized on this site. Coordinates used: 40.7017, -99.0823.

Kearney AC sizing questions