What size heat pump do I need for a 1,500 sq ft house?

About 2.5 to 4 tons. In a mixed climate like Atlanta the estimate is 2.5 tons (cooling load 25,800 BTU/h, heating load 28,500 BTU/h). Hot climates need more cooling capacity and cold climates more heating capacity, as the table shows.

How many BTU do I need for 1,500 square feet?

For cooling, roughly 28,200 BTU/h in a hot, dry climate and 22,200 BTU/h in a cold one. For heating, from 22,500 to 45,000 BTU/h depending on how cold winters get. Older, drafty homes need up to 30% more.

Is it better to oversize or undersize a heat pump?

Neither, but slight undersizing is usually less harmful for cooling. An oversized unit short-cycles and leaves the air clammy. In cold climates, size for the heating load and check the unit’s output at 5°F, or plan for backup heat on the coldest nights.

What size heat pump for a 1,500 sq ft house?

Short answer: 2.5 to 4 tons, depending on your climate and insulation. In a mixed climate like Atlanta: 2.5 tons.

By climate

Hot and dry (Phoenix)2.5 ton
Hot and humid (Houston)2.5 ton
Mixed (Atlanta)2.5 ton
Cold (Chicago)3.5 ton
Very cold (Minneapolis)4 ton

Average insulation, 8 ft ceilings, three occupants.

Best 2.5-ton heat pumps

Most efficient

LG KUSXA301A

2.5 ton central · cold-climate certified

SEER2: 25.0
HSPF2: 10.4
Heat at 5°F: 34,000

Top-rated certified model in the size most 1,500 sq ft homes need.

Full specs and running cost

Best for cold winters

York HH836E2S12

2.5 ton central · LX SERIES · cold-climate certified

SEER2: 18.0
HSPF2: 8.5
COP at 5°F: 2.38

Cold-climate certified, best efficiency at 5°F in this size.

Full specs and running cost

Compare all 2.5-ton heat pumps

Work it out for your home

Pre-filled with 1,500 sq ft. Pick your city and adjust insulation, sun and ceiling height.

Your space

Area to heat and cool sq ftCeiling heightInsulationSun exposurePeople who usually use itIncludes the kitchen?

Your climate

StateCity

Mini-split size: 30,000 BTU
Central / ducted size: 2.5 ton
Cooling load: 28,200 BTU/h
Heating load: 22,500 BTU/h

See 30,000 BTU mini-splits See 2.5-ton central heat pumps

Rule-of-thumb estimate: cooling follows the ENERGY STAR room sizing table, heating uses typical BTU per square foot for the climate (NOAA 1991-2020 heating degree days). For a whole-house system, ask your installer for a Manual J load calculation.

More detail

Cooling and heating loads by climateBTU/h

Hot and dry (Phoenix)cooling 28,200 · heating 22,500
Hot and humid (Houston)cooling 28,200 · heating 22,500
Mixed (Atlanta)cooling 25,800 · heating 28,500
Cold (Chicago)cooling 24,600 · heating 40,500
Very cold (Minneapolis)cooling 22,200 · heating 45,000

Cooling follows the ENERGY STAR sizing table; heating uses BTU per sq ft for the climate (NOAA 1991-2020 normals).

How insulation changes the sizein Atlanta

Poor3 ton · heating 37,100 BTU/h
Average2.5 ton · heating 28,500 BTU/h
Good2 ton · heating 22,800 BTU/h
Very good2 ton · heating 18,500 BTU/h

Top 5 2.5-ton heat pumpsranked by SEER2

#	Model	SEER2	EER2	HSPF2	COP at 5°F
1	LG KUSXA301A	25.0	15.2	10.4	2.10
2	Mitsutomo RU-UZ30-LA-Q	22.3	12.0	9.0	2.10
3	Arcoaire D5CSRAH30AAK	20.5	12.0	9.5	2.10
4	ECOER EODA19H-2436AAalso sold as 1 other model number	20.5	13.0	9.5	2.10
5	Midea MDV-V30WMN10T	20.0	14.0	10.1	2.10

Questions3

What size heat pump do I need for a 1,500 sq ft house?: About 2.5 to 4 tons. In a mixed climate like Atlanta the estimate is 2.5 tons (cooling load 25,800 BTU/h, heating load 28,500 BTU/h). Hot climates need more cooling capacity and cold climates more heating capacity, as the table shows.
How many BTU do I need for 1,500 square feet?: For cooling, roughly 28,200 BTU/h in a hot, dry climate and 22,200 BTU/h in a cold one. For heating, from 22,500 to 45,000 BTU/h depending on how cold winters get. Older, drafty homes need up to 30% more.
Is it better to oversize or undersize a heat pump?: Neither, but slight undersizing is usually less harmful for cooling. An oversized unit short-cycles and leaves the air clammy. In cold climates, size for the heating load and check the unit’s output at 5°F, or plan for backup heat on the coldest nights.

Other sizes

All sizing guides