What size AC for Greenville, TX? 4 tons for 2,000 sq ft

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

4 tons central AC or heat pump, about 48,700 BTU/hr of load

The 20 BTU per square foot chart would put in 3.5 tons, which falls short here. On a design day the unit runs flat out and the house still drifts above 75°F by late afternoon.

If a contractor quotes you more than 4 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 493 square feet in this climate. For a single room, size by the room: 24.3 BTU/hr per square foot.

The climate it is sized for

Climate from NOAA's 1991 to 2020 normals at Greenville Kgvl Radio (3.9 mi away). Aug is the hottest month, averaging a high of 98.3°F and a low of 73.3°F, with about 97 days a year at 90°F or more. That gives a design temperature of 106°F against 75°F inside.

What it costs to run

About 4,328 kWh a year at SEER2 14.3, or roughly $694 at Texas's average residential rate of 16.03¢ per kWh. Cooling runs 7 months of the year here.

What drives the load in Greenville

Of the 48,700 BTU/hr, 22,320 comes through walls, roof and windows on a 106°F afternoon (46%), 13,000 is sun on the house (27%), 2,120 is four people and their appliances, and 11,200 is moisture the coil has to wring out of Greenville's summer air (23%).

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 37,440 BTU/hr before the moisture allowance.

Other house sizes in Greenville

Single rooms with a window or mini-split unit: a 150 sq ft bedroom needs about 3,600 BTU/hr; a 350 sq ft living room needs about 8,500 BTU/hr; a 600 sq ft open plan kitchen and family room needs about 14,600 BTU/hr.

Month by month in Greenville

Aug alone uses 23% of the year's cooling energy. The unit runs the equivalent of 1,272 hours a year at full output.

Greenville against nearby cities

Of 252 Texas cities here, Greenville has the 25th highest cooling load. The range runs from Levelland at 37,300 BTU/hr to Laredo at 51,500.

Where Greenville's weather numbers come from

The nearest NOAA station with full 1991 to 2020 normals is Greenville Kgvl Radio, 3.9 miles from the center of Greenville at 545 ft above sea level. That is close enough that the station's summers are Greenville's summers.

No other city in this set uses Greenville Kgvl Radio, so this sizing is Greenville's alone.

The sun over Greenville in late July

At 33.11°N, the noon sun on 21 July stands 77.3° above the horizon over Greenville and the day runs 13 h 52 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.

34,355 people live in Greenville, the 110th largest of the 252 Texas cities sized on this site. Coordinates used: 33.1119, -96.1103.

Greenville AC sizing questions