What size AC for Peabody, MA? 2 tons for 2,000 sq ft
What size AC a 2,000 sq ft house in Peabody needs
2 tons central AC or heat pump, about 24,900 BTU/hr of load
The 20 BTU per square foot chart would put in 3.5 tons, about 69% 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 2 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 965 square feet in this climate. For a single room, size by the room: 12.4 BTU/hr per square foot.
The climate it is sized for
Climate from NOAA's 1991 to 2020 normals at Beverly Municipal Airport (4.4 mi away). Jul is the hottest month, averaging a high of 81.8°F and a low of 62.2°F, with about 10 days a year at 90°F or more. That gives a design temperature of 86°F against 75°F inside.
What it costs to run
About 798 kWh a year at SEER2 14.3, or roughly $241 at Massachusetts's average residential rate of 30.19¢ per kWh. Cooling runs 4 months of the year here.
What drives the load in Peabody
Of the 24,900 BTU/hr, 7,920 comes through walls, roof and windows on a 86°F afternoon (32%), 13,000 is sun on the house (52%), 2,120 is four people and their appliances, and 1,800 is moisture the coil has to wring out of Peabody's summer air (7%).
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 23,040 BTU/hr before the moisture allowance.
Other house sizes in Peabody
| House | Load, BTU/hr | Size | 20 BTU/ft² chart |
|---|---|---|---|
| 1,000 sq ft | 13,600 | 1.5 tons | 2 tons |
| 1,500 sq ft | 19,200 | 1.5 tons | 2.5 tons |
| 2,500 sq ft | 30,500 | 2.5 tons | 5 tons |
| 3,000 sq ft | 36,200 | 3 tons | 5 tons |
Single rooms with a window or mini-split unit: a 150 sq ft bedroom needs about 1,900 BTU/hr; a 350 sq ft living room needs about 4,300 BTU/hr; a 600 sq ft open plan kitchen and family room needs about 7,400 BTU/hr.
Month by month in Peabody
| Month | Avg high | Cooling degree days | AC kWh |
|---|---|---|---|
| Jan | 36.2°F | 0 | 0 |
| Feb | 38.5°F | 0 | 0 |
| Mar | 45.2°F | 0 | 0 |
| Apr | 56.5°F | 4 | 5 |
| May | 66.5°F | 20 | 26 |
| Jun | 75.8°F | 101 | 132 |
| Jul | 81.8°F | 225 | 294 |
| Aug | 80.7°F | 189 | 246 |
| Sep | 73.4°F | 66 | 86 |
| Oct | 62°F | 6 | 8 |
| Nov | 51.4°F | 0 | 0 |
| Dec | 41.5°F | 0 | 0 |
Jul alone uses 37% of the year's cooling energy. The unit runs the equivalent of 458 hours a year at full output.
Peabody against nearby cities
| City | Distance | Design day | Size for 2,000 sq ft |
|---|---|---|---|
| Lynn, MA | 4 mi | 86°F | 2 tons |
| Salem, MA | 4 mi | 86°F | 2 tons |
| Beverly, MA | 7 mi | 86°F | 2 tons |
| Melrose, MA | 7 mi | 87°F | 2.5 tons |
| Revere, MA | 8 mi | 87°F | 2.5 tons |
| Malden, MA | 9 mi | 87°F | 2.5 tons |
Of 58 Massachusetts cities here, Peabody has the 49th highest cooling load. The range runs from Pittsfield at 22,600 BTU/hr to Framingham at 28,000.
Where Peabody's weather numbers come from
The nearest NOAA station with full 1991 to 2020 normals is Beverly Municipal Airport, 4.4 miles from the center of Peabody at 91 ft above sea level. That is close enough that the station's summers are Peabody's summers.
4 other cities use the same station and get the same climate inputs. The closest to Peabody: Lynn (4 mi away, 7.9 mi from the station), Salem (4 mi away, 5.9 mi from the station), Beverly (7 mi away, 4.1 mi from the station), Gloucester (16 mi away, 12.1 mi from the station). Peabody is farther from the station than 1 of them.
The sun over Peabody in late July
At 42.53°N, the noon sun on 21 July stands 67.9° above the horizon over Peabody and the day runs 14 h 40 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. Long days mean the house keeps gaining heat into the evening, well after the outdoor peak.
55,418 people live in Peabody, the 22nd largest of the 58 Massachusetts cities sized on this site. Coordinates used: 42.5343, -70.9694.
Peabody AC sizing questions
What size AC does a 2,000 sq ft house in Peabody, MA need?
About 2 tons, for a cooling load of 24,900 BTU/hr on a 86°F design day. That is one ton per 965 square feet in Peabody's climate.
Is 20 BTU per square foot right for Peabody?
The chart gives 3.5 tons for 2,000 sq ft, against 2 tons sized from NOAA's 1991 to 2020 normals at Beverly Municipal Airport. For a single room here, plan on 12.4 BTU/hr per square foot.
What does central AC cost to run in Peabody?
About $241 a year: 798 kWh at SEER2 14.3 and 30.19¢ per kWh, over 4 cooling months.