What size AC for Mapleton, UT? 3 tons for 2,000 sq ft

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

3 tons central AC or heat pump, about 35,000 BTU/hr of load

The 20 BTU per square foot chart would put in 3.5 tons, about 20% 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 686 square feet in this climate. For a single room, size by the room: 17.5 BTU/hr per square foot.

The climate it is sized for

Climate from NOAA's 1991 to 2020 normals at Spanish Fk Pwr House (3.1 mi away). Jul is the hottest month, averaging a high of 93.1°F and a low of 61.1°F, with about 60 days a year at 90°F or more. That gives a design temperature of 99°F against 75°F inside.

What it costs to run

About 1,322 kWh a year at SEER2 14.3, or roughly $174 at Utah's average residential rate of 13.19¢ per kWh. Cooling runs 4 months of the year here.

What drives the load in Mapleton

Of the 35,000 BTU/hr, 17,280 comes through walls, roof and windows on a 99°F afternoon (49%), 13,000 is sun on the house (37%), 2,120 is four people and their appliances, and 2,600 is moisture the coil has to wring out of Mapleton's summer air (7%).

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 32,400 BTU/hr before the moisture allowance.

Other house sizes in Mapleton

Single rooms with a window or mini-split unit: a 150 sq ft bedroom needs about 2,600 BTU/hr; a 350 sq ft living room needs about 6,100 BTU/hr; a 600 sq ft open plan kitchen and family room needs about 10,500 BTU/hr.

Month by month in Mapleton

Jul alone uses 37% of the year's cooling energy. The unit runs the equivalent of 540 hours a year at full output.

Mapleton against nearby cities

Of 67 Utah cities here, Mapleton has the 46th highest cooling load. The range runs from Heber at 30,700 BTU/hr to St. George at 49,200.

Where Mapleton's weather numbers come from

The nearest NOAA station with full 1991 to 2020 normals is Spanish Fk Pwr House, 3.1 miles from the center of Mapleton at 4,720 ft above sea level. That is close enough that the station's summers are Mapleton's summers.

2 other cities use the same station and get the same climate inputs. The closest to Mapleton: Spanish Fork (4 mi away, 3.1 mi from the station), Salem (7 mi away, 3.7 mi from the station). Mapleton sits closer to the station than any of them, so its numbers are the best measured of the group.

The sun over Mapleton in late July

At 40.12°N, the noon sun on 21 July stands 70.3° above the horizon over Mapleton and the day runs 14 h 26 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.

14,812 people live in Mapleton, the 56th largest of the 67 Utah cities sized on this site. Coordinates used: 40.1188, -111.5742.

Mapleton AC sizing questions