What size AC for Talladega, AL? 3.5 tons for 2,000 sq ft

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

3.5 tons central AC or heat pump, about 36,900 BTU/hr of load

Here the 20 BTU per square foot chart lands close: 3.5 tons against a load of 3.1 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 651 square feet in this climate. For a single room, size by the room: 18.4 BTU/hr per square foot.

The climate it is sized for

Climate from NOAA's 1991 to 2020 normals at Talladega 10 Nne (10 mi away). Jul is the hottest month, averaging a high of 90°F and a low of 70°F, with about 65 days a year at 90°F or more. That gives a design temperature of 96°F against 75°F inside.

What it costs to run

About 2,713 kWh a year at SEER2 14.3, or roughly $448 at Alabama's average residential rate of 16.51¢ per kWh. Cooling runs 6 months of the year here.

What drives the load in Talladega

Of the 36,900 BTU/hr, 15,120 comes through walls, roof and windows on a 96°F afternoon (41%), 13,000 is sun on the house (35%), 2,120 is four people and their appliances, and 6,700 is moisture the coil has to wring out of Talladega'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 30,240 BTU/hr before the moisture allowance.

Other house sizes in Talladega

Single rooms with a window or mini-split unit: a 150 sq ft bedroom needs about 2,800 BTU/hr; a 350 sq ft living room needs about 6,400 BTU/hr; a 600 sq ft open plan kitchen and family room needs about 11,000 BTU/hr.

Month by month in Talladega

Jul alone uses 25% of the year's cooling energy. The unit runs the equivalent of 1,051 hours a year at full output.

Talladega against nearby cities

Of 66 Alabama cities here, Talladega has the 47th highest cooling load. The range runs from Boaz at 30,600 BTU/hr to Montgomery at 44,000.

Where Talladega's weather numbers come from

The nearest NOAA station with full 1991 to 2020 normals is Talladega 10 Nne, 10 miles from the center of Talladega at 525 ft above sea level. That is close enough that the station's summers are Talladega's summers.

1 other city uses the same station and get the same climate inputs. The closest to Talladega: Pell City (13 mi away, 11.9 mi from the station). Talladega sits closer to the station than any of them, so its numbers are the best measured of the group.

The sun over Talladega in late July

At 33.43°N, the noon sun on 21 July stands 77.0° above the horizon over Talladega and the day runs 13 h 54 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.

14,693 people live in Talladega, the 49th largest of the 66 Alabama cities sized on this site. Coordinates used: 33.4318, -86.0995.

Talladega AC sizing questions