What size AC for Bainbridge, GA? 3.5 tons for 2,000 sq ft

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

3.5 tons central AC or heat pump, about 38,700 BTU/hr of load

Here the 20 BTU per square foot chart lands close: 3.5 tons against a load of 3.2 tons. This is one of the climates the chart was written for.

If a contractor quotes you more than 3.5 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 621 square feet in this climate. For a single room, size by the room: 19.3 BTU/hr per square foot.

The climate it is sized for

Climate from NOAA's 1991 to 2020 normals at Newton 11 Sw (21.2 mi away). Jul is the hottest month, averaging a high of 90.9°F and a low of 71.3°F, with about 79 days a year at 90°F or more. That gives a design temperature of 98°F against 75°F inside.

What it costs to run

About 3,483 kWh a year at SEER2 14.3, or roughly $539 at Georgia's average residential rate of 15.48¢ per kWh. Cooling runs 7 months of the year here.

What drives the load in Bainbridge

Of the 38,700 BTU/hr, 16,560 comes through walls, roof and windows on a 98°F afternoon (43%), 13,000 is sun on the house (34%), 2,120 is four people and their appliances, and 7,000 is moisture the coil has to wring out of Bainbridge'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 31,680 BTU/hr before the moisture allowance.

Other house sizes in Bainbridge

Single rooms with a window or mini-split unit: a 150 sq ft bedroom needs about 2,900 BTU/hr; a 350 sq ft living room needs about 6,800 BTU/hr; a 600 sq ft open plan kitchen and family room needs about 11,600 BTU/hr.

Month by month in Bainbridge

Jul alone uses 21% of the year's cooling energy. The unit runs the equivalent of 1,289 hours a year at full output.

Bainbridge against nearby cities

Of 101 Georgia cities here, Bainbridge has the 27th highest cooling load. The range runs from Cumming at 33,100 BTU/hr to Albany at 44,000.

Where Bainbridge's weather numbers come from

The nearest NOAA station with full 1991 to 2020 normals is Newton 11 Sw, 21.2 miles from the center of Bainbridge at 156 ft above sea level. That is close enough that the station's summers are Bainbridge's summers.

No other city in this set uses Newton 11 Sw, so this sizing is Bainbridge's alone.

The sun over Bainbridge in late July

At 30.90°N, the noon sun on 21 July stands 79.5° above the horizon over Bainbridge and the day runs 13 h 43 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.

14,586 people live in Bainbridge, the 83rd largest of the 101 Georgia cities sized on this site. Coordinates used: 30.9049, -84.5730.

Bainbridge AC sizing questions