ACSizeCheck

What size AC for Vienna, WV? 3 tons for 2,000 sq ft

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

3 tons central AC or heat pump, about 31,500 BTU/hr of load

The 20 BTU per square foot chart would put in 3.5 tons, about 33% 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 763 square feet in this climate. For a single room, size by the room: 15.7 BTU/hr per square foot.

The climate it is sized for

Climate from NOAA's 1991 to 2020 normals at Parkersburg (3.2 mi away). Jul is the hottest month, averaging a high of 86.6°F and a low of 65.9°F, with about 29 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 1,638 kWh a year at SEER2 14.3, or roughly $255 at West Virginia's average residential rate of 15.58¢ per kWh. Cooling runs 5 months of the year here.

What drives the load in Vienna

Of the 31,500 BTU/hr, 12,240 comes through walls, roof and windows on a 92°F afternoon (39%), 13,000 is sun on the house (41%), 2,120 is four people and their appliances, and 4,100 is moisture the coil has to wring out of Vienna's summer air (13%).

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 Vienna

HouseLoad, BTU/hrSize20 BTU/ft² chart
1,000 sq ft17,0001.5 tons2 tons
1,500 sq ft24,2002 tons2.5 tons
2,500 sq ft38,7003.5 tons5 tons
3,000 sq ft46,0004 tons5 tons

Single rooms with a window or mini-split unit: a 150 sq ft bedroom needs about 2,400 BTU/hr; a 350 sq ft living room needs about 5,500 BTU/hr; a 600 sq ft open plan kitchen and family room needs about 9,400 BTU/hr.

Month by month in Vienna

MonthAvg highCooling degree daysAC kWh
Jan40.4°F00
Feb44.2°F00
Mar53.8°F23
Apr66.8°F1724
May75.5°F90125
Jun83°F235327
Jul86.6°F349485
Aug85.7°F311433
Sep79.8°F151210
Oct67.6°F2231
Nov55°F11
Dec44.5°F00

Jul alone uses 30% of the year's cooling energy. The unit runs the equivalent of 745 hours a year at full output.

Vienna against nearby cities

CityDistanceDesign daySize for 2,000 sq ft
Parkersburg, WV4 mi92°F3 tons
Marietta, OH8 mi90°F2.5 tons
Athens, OH30 mi87°F2 tons
Cambridge, OH48 mi90°F2.5 tons
Zanesville, OH51 mi89°F2.5 tons
Clarksburg, WV63 mi90°F2.5 tons

Of 13 West Virginia cities here, Vienna has the 3rd highest cooling load. The range runs from Beckley at 24,100 BTU/hr to Parkersburg at 31,500.

Where Vienna's weather numbers come from

The nearest NOAA station with full 1991 to 2020 normals is Parkersburg, 3.2 miles from the center of Vienna at 620 ft above sea level. That is close enough that the station's summers are Vienna's summers.

1 other city uses the same station and get the same climate inputs. The closest to Vienna: Parkersburg (4 mi away, 1.6 mi from the station). Vienna is farther from the station than 1 of them.

The sun over Vienna in late July

At 39.32°N, the noon sun on 21 July stands 71.1° above the horizon over Vienna and the day runs 14 h 22 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.

10,406 people live in Vienna, the 12th largest of the 13 West Virginia cities sized on this site. Coordinates used: 39.3228, -81.5298.

Vienna AC sizing questions

What size AC does a 2,000 sq ft house in Vienna, WV need?

About 3 tons, for a cooling load of 31,500 BTU/hr on a 92°F design day. That is one ton per 763 square feet in Vienna's climate.

Is 20 BTU per square foot right for Vienna?

The chart gives 3.5 tons for 2,000 sq ft, against 3 tons sized from NOAA's 1991 to 2020 normals at Parkersburg. For a single room here, plan on 15.7 BTU/hr per square foot.

What does central AC cost to run in Vienna?

About $255 a year: 1,638 kWh at SEER2 14.3 and 15.58¢ per kWh, over 5 cooling months.