What size AC for Warrensburg, MO? 3 tons for 2,000 sq ft

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

3 tons central AC or heat pump, about 33,900 BTU/hr of load

The 20 BTU per square foot chart would put in 3.5 tons, about 24% 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 707 square feet in this climate. For a single room, size by the room: 17 BTU/hr per square foot.

The climate it is sized for

Climate from NOAA's 1991 to 2020 normals at Warrensburg 4nw (4.3 mi away). Jul is the hottest month, averaging a high of 89.8°F and a low of 66.8°F, with about 40 days a year at 90°F or more. That gives a design temperature of 95°F against 75°F inside.

What it costs to run

About 1,884 kWh a year at SEER2 14.3, or roughly $269 at Missouri's average residential rate of 14.28¢ per kWh. Cooling runs 5 months of the year here.

What drives the load in Warrensburg

Of the 33,900 BTU/hr, 14,400 comes through walls, roof and windows on a 95°F afternoon (42%), 13,000 is sun on the house (38%), 2,120 is four people and their appliances, and 4,400 is moisture the coil has to wring out of Warrensburg's summer air (13%).

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 29,520 BTU/hr before the moisture allowance.

Other house sizes in Warrensburg

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 6,000 BTU/hr; a 600 sq ft open plan kitchen and family room needs about 10,200 BTU/hr.

Month by month in Warrensburg

Jul alone uses 30% of the year's cooling energy. The unit runs the equivalent of 794 hours a year at full output.

Warrensburg against nearby cities

Of 80 Missouri cities here, Warrensburg has the 62nd highest cooling load. The range runs from Hannibal at 30,600 BTU/hr to Sikeston at 37,800.

Where Warrensburg's weather numbers come from

The nearest NOAA station with full 1991 to 2020 normals is Warrensburg 4nw, 4.3 miles from the center of Warrensburg at 796 ft above sea level. That is close enough that the station's summers are Warrensburg's summers.

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

The sun over Warrensburg in late July

At 38.76°N, the noon sun on 21 July stands 71.6° above the horizon over Warrensburg and the day runs 14 h 19 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.

19,998 people live in Warrensburg, the 37th largest of the 80 Missouri cities sized on this site. Coordinates used: 38.7624, -93.7253.

Warrensburg AC sizing questions