Aircon HP and Room Size: What Each Size Cools, 0.5 to 2.5 HP

These are the same ranges our aircon HP calculator uses. A shaded room means a normal ceiling, two people and no afternoon sun. A hot room means afternoon sun and a room under the roof with no ceiling insulation. For a high ceiling, a kitchen or a room that holds more people, put it through the calculator, which counts each of those.

Aircon size by room, at a glance

1. 1 Dark bar: a shaded room. Normal ceiling, two people, no afternoon sun. This is the calculator with nothing added.
2. 2 Pale bar: afternoon sun under an uninsulated roof. The same unit covers a noticeably smaller room, which is why the hot room steps up a size.

0.5 HP aircon room size

up to 8 square metres in shade, up to 6.3 in a hot room. A 2.5 by 3 metre room is 7.5 square metres. A small bedroom, a helper’s room or a study.

Mostly sold as window type. It is the smallest size there is, so a room near the top of its range with any afternoon sun is a 0.75 room.

0.6 HP aircon room size

8 to 9 square metres in shade, 6.3 to 7.1 in a hot room. A 3 by 3 metre room is 9 square metres. A small bedroom that is a little too big for 0.5.

Sold almost only as window type, and not one of the calculator’s bands. Its range is arithmetic: six tenths of the 9,000 BTU per hour a 1.0 HP unit gives is about 5,400, and at the roughly 600 BTU per hour per square metre these ranges work out to, that cools about 9 square metres in shade.

0.75 HP aircon room size

8 to 12 square metres in shade, 6.3 to 9.5 in a hot room. A 3 by 4 metre room is 12 square metres. A standard small bedroom.

The step people skip, going from 0.5 straight to 1.0. In a shaded 10 to 12 square metre bedroom it is the right size, and the larger one cools fast and leaves the air damp.

1 HP aircon room size

12 to 16 square metres in shade, 9.5 to 12.6 in a hot room. A 4 by 4 metre room is 16 square metres. Most ordinary bedrooms.

The size most people ask for first, and the one most easily put in a room that is too hot for it. Under the roof with afternoon sun, it covers only about 10 to 13 square metres. What it draws is on the 1 HP aircon power consumption section of our watts guide.

1.5 HP aircon room size

16 to 22 square metres in shade, 12.6 to 17.4 in a hot room. A 4 by 5 metre room is 20 square metres. A master bedroom, or a small living room.

Also the usual answer for a 1.0 HP-sized bedroom on the top floor in the afternoon sun.

2 HP aircon room size

22 to 30 square metres in shade, 17.4 to 23.7 in a hot room. A 5 by 6 metre room is 30 square metres. A living room, or a bedroom with an open area.

Where the type starts to matter as much as the size. A 2.0 HP window type is a lot of noise in a living room, which is where a split type earns its install.

2.5 HP aircon room size

30 to 40 square metres in shade, 23.7 to 31.6 in a hot room. A 5 by 8 metre room is 40 square metres. A large living and dining area.

Above about 40 square metres in shade, or 30 in a hot room, two smaller units usually cool better than one large one, because the far end of a long room never feels the air from a single unit.

Why a manufacturer's chart gives bigger rooms

If you have seen a different table, you are not imagining it. Midea Philippines' own size guide, published in May 2026, puts every size against a larger room than ours. It gives 1.0 HP for 18 to 22 square metres, where we say up to 16 in shade.

1. 1 Dark: our shaded range. What the calculator gives with nothing added.
2. 2 Outlined: the Midea guide. A bigger room for every size, before its own advice to step up for sun, high ceilings and a top floor.

The same guide then tells you to size up half a step for a ceiling above 3 metres, a west-facing wall or a lot of glass, and a full step for a top-floor room in direct sun. Apply those and the gap narrows. A 20 square metre top-floor bedroom in the afternoon sun goes from 1.0 to 1.5 HP on their rules, and comes out at 2.0 on ours, so ours is still the more cautious of the two. It starts from a shaded room and adds the heat in, where that table starts from an easy room and leaves the step-up to you. If the two disagree for your room, the sun and the roof decide it. A shaded room can take their figure. A hot one is safer on ours.

Before you buy

The size is half of the decision. The other half is the type, which decides the install, the noise and where the unit can go: types of aircon covers split, window, portable and centralized. Once you know both, our aircon installation visit checks the wall, the outdoor spot, the drain and the circuit before anything is drilled, and tells you if the room is going to need a different size than the chart says.

Questions people ask

How many square metres can a 1 HP aircon cool?

About 12 to 16 square metres in a shaded room with a normal ceiling and two people. With afternoon sun under an uninsulated roof, about 10 to 13.

What is the room size for a 1.5 HP aircon?

About 16 to 22 square metres in shade, and about 13 to 17 in a hot room under the roof. A master bedroom or a small living room.

Is a 2 HP aircon enough for 30 square metres?

In a shaded room, yes, at the top of its range. With afternoon sun or a hot roof above it, 30 square metres wants 2.5 HP.

What size aircon does a 3 by 3 metre room need?

That is 9 square metres. In shade, a 0.75 HP, or a 0.6 HP window type. Under the roof with afternoon sun, 1.0 HP.

Is window type aircon sizing different from split type?

No. A room needs the same cooling whichever type delivers it, so the HP is the same. Window types are mostly sold in the smaller sizes, and above 1.5 HP most people choose a split for the noise.

Other guides

• Aircon capacitor: what it does and the signs it has failed

  The humming outdoor unit, the fan that will not spin, and why the capacitor is tested first.

• Aircon freezing up: why ice forms and what to do

  Ice on the indoor coil or the pipes, how to thaw it safely, and the three causes behind it.

• Aircon making noise: which sounds are normal and which are not

  Clicks and water sounds that are normal, and the rattles, hisses and squeals that need a technician.

• Aircon not turning on: what to check, and the 3-minute wait after a brownout

  Remote, breaker, the compressor’s restart delay, and the flashing lamp that means a technician.

• AVR for aircon: when you need one and how to size it

  What an AVR does in a brownout, which units already protect themselves, and sizing it from the nameplate.

• Aircon watts: how many watts a 1 HP aircon uses, size by size

  Running watts and kWh per hour for each size, how to read the nameplate, and starting watts for a generator.

• Types of aircon: split type, window type, portable and centralized

  How each is installed, how noisy and costly to run it is, which rooms suit it, and what a clean has to reach.

• What is freon, and why your aircon should not need a yearly refill

  The sealed loop, why low gas means a leak, the three refrigerants in Philippine units, and the refill myth.

• Aircon cleaning schedule: what to clean, and how often

  The filter every two weeks, a full clean by how hard the unit works, the deeper clean, and when in the year to book it.

• Common aircon problems, symptom by symptom

  Not cold, weak air, water inside, a smell, ice, noise, tripping and blinking: what each points to and what you can check.

• Aircon lifespan: how long it lasts, and repair or replace

  How many years a unit usually gives, what shortens it, and the signs that a repair is no longer worth it.

• Inverter vs non-inverter aircon: which costs less to run

  Kilowatt hours side by side at 2, 4, 8 and 12 hours a day, and the kind of use where a non-inverter is still fine.

• What size aircon for a bedroom, living room or kitchen

  Room by room: what each kind of room adds to the size you need, worked through for a sample two-storey house.

• Aircon energy saving tips that lower the bill

  Where the heat gets in, the setting and the fan, the timer, the cleaning, and reading the DOE energy label.

Sources: the ranges are this site's own, derived from the bands in our aircon HP calculator. The comparison table and step-up rules are read from Midea Philippines, “Air Conditioner Size Guide for Filipino Homes”, published 14 May 2026 and read 8 October 2026. Midea is named as the source of a table and is not recommended.