Choose cassette AC capacity by starting with the room’s floor area, then account for ceiling height, sun and glass exposure, occupancy, equipment, lighting, and operating hours. Area charts give only a preliminary range: use a guide for your market, compare models by rated cooling capacity, and have an HVAC professional verify the room load and ceiling installation before you buy.
What size cassette AC do you need for your room?
Measure the room and use a manufacturer’s area guide from the country where you plan to buy. Treat its result as an initial capacity band, not a final specification. Different manufacturers use different regions, units, products, and assumptions, so their charts should not be combined into a universal formula.
Voltas’s general cassette guide (square feet and tons)
Voltas gives these starting ranges in an undated general guide for cassette ACs in commercial spaces, accessed in 2026:
| Room area | Voltas starting capacity |
|---|---|
| Up to 150 sq ft | 1.0–1.5 ton |
| 150–300 sq ft | 1.5–2.0 ton |
| 300–500 sq ft | 2.0–3.0 ton |
| 500–800 sq ft | 3.0–4.0 ton |
| 800 sq ft or more | 4.0 ton and above; multiple units may be appropriate |
These are Voltas’s broad guide ranges, not an engineering rule for every room. Voltas notes that ceiling height affects performance and that higher spaces may require more capacity or multiple units. Voltas’s cassette AC guide.
Free tools Windows power users keep installed
One-click scans. No signup required.
#1 Best Overall
- Exceptional Cooling & Efficiency: The DELLA ceiling cassette mini split 12,000 BTU/h of cooling power at 208-230 V. UL/ETL listed and AHRI certified. With a high 22 SEER2 rating, it ensures energy-efficient performance. The heat pump works in temperatures as low as -13 ℉ (-25 ℃), providing consistent comfort for spaces up to 550 sq ft.
- Versatile System: The DELLA ceiling cassette system features 360° surround airflow for more even air distribution, fitting various interior layouts and creating a sleek. Equipped with refrigerant leak sensor, 24-hour timer, multiple fan speeds, sleep, energy-saving, cooling, heating, dehumidifying, and auto modes. Ideal for offices, shops, restaurants, and warehouses as a commercial comfort solution.
- Quiet & Smart Performance: Operating at just 32 dB(A), it runs nearly silent, ensuring it won't disrupt your daily routine. It quickly adjusts room temperatures from 60 to 90 °F for instant comfort. Compatible with the DELLA App and multiple voice assistants, enabling remote control from anywhere. Thanks to the geolocation feature, you can remotely start the system before you arrive home for a perfectly timed indoor climate.
- Advanced Technology: The outdoor unit uses advanced inverter technology for energy efficiency and reduced consumption. It features a bottom-mounted heater to prevent frost buildup, ensuring reliable operation even in extreme cold as low as -13 ℉ (-25 ℃). PureClean technology prevents indoor dust accumulation with one-touch auto-cleaning, maintaining fresh air. Energy Star certified, DELLA ceiling cassette AC qualifies for government energy rebates.
- Installation Kit: Comes with 16 ft copper tube (1/4" and 3/8" ). Max fuse rating is 15A. Tube must be purged and vacuumed during installation. No refrigerant adjustment needed if tube is under 25 ft; over 25 ft requires adjustment according to the manual. Professional installation required. Pre-charged R454B refrigerant, supporting up to 25 ft.
Midea Malaysia’s guide (square metres and horsepower)
Midea Malaysia publishes a different regional guide. Its unit is horsepower (HP), not tons:
| Room area | Midea Malaysia starting capacity |
|---|---|
| 12–25 m² | 1.5–2.0 HP |
| 25–40 m² | 2.5–3.0 HP |
| 40–60 m² | 3.5–4.0 HP |
| 60 m² or more | 4.5–5.0 HP |
Midea says to account for ceiling height, occupancy, glass exposure, kitchen equipment, lighting loads, and daily operating hours. It recommends a professional site assessment for commercial projects rather than relying on floor area alone. The figures above are Midea Malaysia guidance, not a cross-market conversion or universal cassette sizing chart. Midea Malaysia’s cassette AC guide.
Rank #2
- Exceptional Cooling & Efficiency: The DELLA ceiling cassette mini split 18,000 BTU/h of cooling power at 208-230 V. UL/ETL listed and AHRI certified. With a high 20.5 SEER2 rating, it ensures energy-efficient performance. The heat pump works in temperatures as low as -13 ℉ (-25 ℃), providing consistent comfort for spaces up to 1000 sq ft.
- Quiet & Smart Performance: Operating at just 37 dB(A), it runs nearly silent, ensuring it won't disrupt your daily routine. It quickly adjusts room temperatures from 60 to 90 °F for instant comfort. Compatible with the DELLA App and multiple voice assistants, enabling remote control from anywhere. Thanks to the geolocation feature, you can remotely start the system before you arrive home for a perfectly timed indoor climate.
- Versatile System: The DELLA ceiling cassette system features 360° surround airflow for more even air distribution, fitting various interior layouts and creating a sleek. Equipped with refrigerant leak sensor, 24-hour timer, multiple fan speeds, sleep, energy-saving, cooling, heating, dehumidifying, and auto modes. Ideal for offices, shops, restaurants, and warehouses as a commercial comfort solution.
- Advanced Technology: The outdoor unit uses advanced inverter technology for energy efficiency and reduced consumption. It features a bottom-mounted heater to prevent frost buildup, ensuring reliable operation even in extreme cold as low as -13 ℉ (-25 ℃). PureClean technology prevents indoor dust accumulation with one-touch auto-cleaning, maintaining fresh air. Energy Star certified, DELLA ceiling cassette AC qualifies for government energy rebates.
- Installation Kit: Comes with 16 ft copper tube (1/4" and 1/2" ). Max fuse rating is 20A. Tube must be purged and vacuumed during installation. No refrigerant adjustment needed if tube is under 25 ft; over 25 ft requires adjustment according to the manual. Professional installation required. Pre-charged R454B refrigerant, supporting up to 25 ft.
Why other AC charts may not apply
Daikin Indonesia’s general AC guide, for example, gives room ranges in square metres alongside PK (metric horsepower): up to 12 m² at ½–¾ PK, 12–25 m² at 1–1½ PK, and over 25 m² at 2 PK or above. It is general AC guidance, not a cassette-specific chart. Its calculator also considers room dimensions, sun direction, occupant count, and home condition. Daikin Indonesia’s AC capacity calculator.
Likewise, Samsung Saudi Arabia’s general AC examples—1 ton for 90–120 sq ft, 1.5 ton for 120–180 sq ft, and 2 ton for spaces over 180 sq ft—are not a cassette-specific sizing table. Samsung Saudi Arabia’s AC guide. These examples illustrate why you should use the intended market’s product documentation instead of splicing charts together.
Rank #3
- Powerful All-Season Comfort: Experience steady cooling on 95°F days and reliable heating when it's 47°F outside. This 12000 BTU ceiling spilit air conditioner keeps room comfortably consistent all year
- 360° Even & Quiet Airflow: Six fan speeds and Turbo mode quickly adjust temperature. Mute mode runs quietly at 32 dB(A) for undisturbed rest or work. Recessed ceiling design ensures wide, balanced air circulation
- Energy-Efficient & Cost-Saving: This Garvee split AC uses R454B refrigerant for outstanding energy efficiency and system adaptability. It removes 1.1L of excess humidity hourly to keep your space dry and comfortable year-round
- Low-Profile & Easy to Install: Slim 9.6in height and 25.62in square panel fit seamlessly into most ceilings. Lightweight design and standard wiring/piping make professional installation simpler and faster
- Versatile Applications: Garvee Ceiling Cassette AC is ideal for small-to-medium spaces: commercial offices, meeting rooms, retail stores, cafes, community service centers, small classrooms, large home living/dining areas and compact gyms
How do you calculate cassette AC capacity?
A floor-area chart does not calculate the room’s full cooling load. Use this sequence to narrow the options, then get the final capacity checked against the room and installation.
- Measure the room. Record floor area and ceiling height, along with how the room is used and its typical occupancy.
- Identify added heat loads. Note extensive glazing or direct sun, kitchen equipment, lighting, and long daily operating hours. These factors can change the appropriate capacity; the available manufacturer guidance does not establish a universal multiplier for them.
- Choose a local starting guide. Use a manufacturer chart for the intended market and product type. Do not convert or combine tons, HP, or PK by label alone.
- Compare rated cooling capacity. Check the candidate model’s stated cooling capacity and specifications rather than relying only on a product label such as “ton” or “HP.”
- Match airflow to the room. Consider the room shape, cassette airflow direction, and where conditioned air needs to travel.
- Check ceiling and installation constraints. Confirm the unit body and panel fit, drainage route and gradient, refrigerant piping, electrical service, placement, and future service access.
- Have the selection verified. Ask a qualified HVAC installer or designer to check the load and installation before ordering, particularly for commercial, high-ceiling, sun-exposed, densely occupied, or equipment-heavy rooms.
Compare models using rated cooling capacity, not just a label
Rated cooling capacity is a more useful basis for comparing candidates than a nominal label alone. Keep the comparison in consistent units and check the manufacturer’s conditions and market-specific specifications. Daikin India lists FCA cassette models with rated cooling capacities of 5.0, 7.1, 12.5, and 14.0 kW. Those values describe that India-specific product range; they do not identify the right capacity for a particular room. Daikin India’s FCA cassette specifications.
Rank #4
- High-Efficiency Cooling & Heating: The DELLA ceiling cassette mini split AC provides 42,000 BTU/h, 208-230 V. UL/ETL listed and AHRI certified for safety and performance. With a 22 SEER2 rating, it delivers strong, consistent cooling and heating. The heat pump supports year round comfort, operating even in temperatures as low as -13F (-25C)
- Multi-Zone Coverage: This system provides cooling and heating for areas up to 2600 sq. ft. (4 indoor unit recommended area 400 Sq. Ft, another one 1000 Sq. Ft) and comes with separate controllers for each room, allowing independent temperature control for comfort. Includes 5 x 25 ft copper pipes lineset (Standard size 1/4" & 1/2", 4* 1/4" & 3/8" outer dimension) and a complete installation kit
- Versatile System: The DELLA ceiling cassette system features 360 surround airflow for more even air distribution, fitting various interior layouts and creating a sleek appearance. Equipped with refrigerant leak sensor, 24-hour timer, multiple fan speeds, sleep, energy-saving, cooling, heating, dehumidifying, and auto modes. Suitable for offices, shops, restaurants, and warehouses as a commercial comfort solution
- Quiet & Professional Installation: Operating at just 32 dB(A), it runs nearly silently, ensuring it won't disrupt your daily routine. During installation, the line set must be properly evacuated and vacuumed. This system mandates professional installation - it's not a DIY mini split AC. Equipped with a bottom heating element, the outdoor unit prevents ice buildup during winter operation, ensuring efficient defrosting and reliable performance. Maximum Fuse Size is 45A
- Multi Zone Capacity: This configuration is designed for spaces where not all indoor units are expected to operate at full power at the same time. If the total indoor capacity is higher than the outdoor unit's output, the system can still function properly, but cooling or heating performance may be slower when all zones are operating beyond capacity. For consistently high demand across all zones, a larger or multi-system setup is recommended
Daikin states that the FCA rated values use indoor conditions of 27°C dry-bulb/19.0°C wet-bulb and outdoor conditions of 35°C dry-bulb, with 7.5 m equivalent horizontal piping. They are product specifications under those stated test conditions, not a prediction of performance in every installation. For a fair model comparison, also review the manufacturer’s efficiency and electrical specifications under their stated conditions, plus local warranty and installation support.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Choose airflow direction for the room’s shape
Capacity and airflow configuration solve different problems: the first concerns the cooling load; the second concerns how air is distributed. A cassette is recessed into a false ceiling, leaving walls free. Voltas describes a central intake with air discharged through side vents and associates these formats with different room layouts:
Best Value
- [High-Efficiency Cooling & Heating]: The DELLA ceiling cassette mini split AC provides 18,000 BTU/h, 208-230 V. UL/ETL listed and AHRI certified for safety and performance. With a 24 SEER2 rating, it delivers strong, consistent cooling and heating. The heat pump supports year round comfort, operating even in temperatures as low as -13 ℉ (-25 ℃).
- [Multi-Zone Coverage]: This system provides cooling and heating for areas up to 1100 sq. ft. (each indoor unit recommended area 550 Sq. Ft) and comes with separate controllers for each room, allowing independent temperature control for ideal comfort. Includes 2 x 25 ft copper pipes lineset (standard 1/4" and 3/8" outer dimension) and a complete installation kit.
- [Versatile System]: The DELLA ceiling cassette system features 360° surround airflow for more even air distribution, fitting various interior layouts and creating a sleek. Equipped with refrigerant leak sensor, 24-hour timer, multiple fan speeds, sleep, energy-saving, cooling, heating, dehumidifying, and auto modes. Ideal for offices, shops, restaurants, and warehouses as a commercial comfort solution.
- [Quiet & Professional Installation]: Operating at just 32 dB(A), it runs nearly silently, ensuring it won't disrupt your daily routine.During installation, the line set must be properly evacuated and vacuumed.This system mandates professional installation - it's not a DIY mini split AC.Equipped with a bottom heating element, the outdoor unit prevents ice buildup during winter operation, ensuring efficient defrosting and reliable performance.Maximum Fuse Size is 25A.
- [Multi Zone Capacity]: This configuration is designed for spaces where not all indoor units are expected to operate at full power at the same time. If the total indoor capacity is higher than the outdoor unit’s output, the system can still function properly, but cooling or heating performance may be slower when all zones are operating beyond capacity. For consistently high demand across all zones, a larger or multi-system setup is recommended.
| Airflow format | Voltas’s suggested room fit |
|---|---|
| One-way | Narrow spaces |
| Two-way | Medium rectangular spaces |
| Four-way | Wide, open areas |
These are general suggestions; confirm the selected model’s airflow and placement requirements. Daikin Australia says, “As such, a ceiling cassette should be installed in the centre of the room to provide the best possible distribution of conditioned air.” Treat that as Daikin Australia’s installation guidance, not a rule that overrides a site-specific design. Daikin Australia’s ceiling-cassette FAQ.
Check the ceiling before choosing a unit
A cassette installation requires more than enough visible ceiling space. The ceiling void must accommodate the model’s body depth, panel, drainage gradient, piping, and service access. Midea notes that installation involves a ceiling cut-out, refrigerant piping, drainage, electrical connection, and commissioning; its example dimensions apply to specific units, not every cassette. Voltas also recommends planning access panels and periodically inspecting drainage lines. Midea Malaysia’s installation guidance; Voltas’s cassette AC guide.
- Verify the ceiling structure and available void against the exact model’s dimensions.
- Plan a condensate drainage route with the required gradient.
- Confirm refrigerant-pipe routing and electrical service requirements.
- Allow access for filter cleaning, drainage inspection, and servicing.
- Confirm that the proposed placement works with the room layout and airflow.
Installation-channel details are local: Midea’s reference to authorized channels applies to Malaysia and should not be assumed to describe purchasing or installation arrangements elsewhere.
When is a professional load assessment especially important?
Ask an HVAC professional to assess the room rather than relying on area alone if it has a high ceiling, substantial sun or glass exposure, unusual geometry, heavy equipment, dense occupancy, or commercial operating demands. Midea specifically favors a professional site assessment for commercial projects. Daikin Indonesia’s calculator illustrates that room dimensions, sun direction, occupant count, and home condition can all affect an estimate, but its general AC calculator is not a substitute for cassette-specific design.
Quick wins for a faster PC:
Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Repair Windows errors before they cause bigger problemsFix Now →For maintenance after installation, Voltas recommends regular filter cleaning to help maintain airflow and periodic drainage-line inspection. Follow the selected model’s own maintenance instructions.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
