What size AC for Covington, LA? 3.5 tons for 2,000 sq ft

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

3.5 tons central AC or heat pump, about 37,800 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 635 square feet in this climate. For a single room, size by the room: 18.9 BTU/hr per square foot.

The climate it is sized for

Climate from NOAA's 1991 to 2020 normals at Covington 4 Nnw (3.2 mi away). Jul is the hottest month, averaging a high of 90.1°F and a low of 71.3°F, with about 83 days a year at 90°F or more. That gives a design temperature of 97°F against 75°F inside.

What it costs to run

About 3,547 kWh a year at SEER2 14.3, or roughly $471 at Louisiana's average residential rate of 13.27¢ per kWh. Cooling runs 7 months of the year here.

What drives the load in Covington

Of the 37,800 BTU/hr, 15,840 comes through walls, roof and windows on a 97°F afternoon (42%), 13,000 is sun on the house (34%), 2,120 is four people and their appliances, and 6,800 is moisture the coil has to wring out of Covington'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 30,960 BTU/hr before the moisture allowance.

Other house sizes in Covington

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 6,600 BTU/hr; a 600 sq ft open plan kitchen and family room needs about 11,300 BTU/hr.

Month by month in Covington

Aug alone uses 20% of the year's cooling energy. The unit runs the equivalent of 1,343 hours a year at full output.

Covington against nearby cities

Of 35 Louisiana cities here, Covington has the lowest cooling load. The range runs from Covington at 37,800 BTU/hr to Natchitoches at 45,900.

Where Covington's weather numbers come from

The nearest NOAA station with full 1991 to 2020 normals is Covington 4 Nnw, 3.2 miles from the center of Covington at 40 ft above sea level. That is close enough that the station's summers are Covington's summers.

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

The sun over Covington in late July

At 30.48°N, the noon sun on 21 July stands 79.9° above the horizon over Covington and the day runs 13 h 41 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.

11,686 people live in Covington, the 30th largest of the 35 Louisiana cities sized on this site. Coordinates used: 30.4802, -90.1118.

Covington AC sizing questions