How to Choose Your Portable Air Conditioner: 8 Criteria
Selecting a portable air conditioner requires evaluating 8 essential criteria: room size, BTU power, noise level, energy efficiency, evacuation type and additional functions. This guide helps you

Why Choose Your Portable Air Conditioner Carefully?
An unsuitable portable air conditioner consumes unnecessarily and cools poorly. The choice rests on 8 measurable criteria that guarantee comfort, energy savings and durability. This checklist guides you toward the device matching your real needs and budget.
Criterion 1: What Surface Should Your Air Conditioner Cool?
Room size is the primary determinant. For a 20 m² room, count 7,000 BTU minimum; for 30 m², 10,500 BTU. Measure your m² precisely (length × width) and consult the manufacturer's conversion table. Undersized power leaves the room warm; excessive power increases consumption without benefit.
Measuring and Calculating Surface Area
Note the length and width of the room. Multiply these two figures. For a bedroom of 4 m × 5 m, you get 20 m². Mentally isolate zones: if a room directly connects to another uncooled space, add 20% to the surface. Very sunny rooms also require +10% power.
Criterion 2: How Many BTU Are Needed for Effective Cooling?
BTU (British Thermal Unit) measures cooling capacity. Standard rule: 35 BTU per m² in temperate climate, 40-45 BTU/m² in very hot regions. For 25 m², aim for 875 to 1,125 BTU. Consult the technical sheets of models and compare with [ADEME's recommendation on air conditioner energy efficiency](https://www.ademe.fr/particuliers-eco-citoyens/habiter/climatisation-efficace).
BTU/Surface Reference Table
- 10-15 m²: 5,000-7,000 BTU
- 15-20 m²: 7,000-9,000 BTU
- 20-30 m²: 9,000-12,000 BTU
- 30-40 m²: 12,000-15,000 BTU
Criterion 3: What Noise Level Does Your Environment Tolerate?
Portable air conditioner noise ranges from 60 to 75 dB. In a bedroom, prefer <65 dB for undisturbed sleep. In a living room, up to 70 dB remains acceptable. Check exact decibels in product sheets; Aether Climate models display this data transparently. A quiet device improves daily comfort, especially for remote work or rest.
Understanding the Decibel Scale
- 60 dB: normal conversation
- 65 dB: quiet air conditioner (acceptable for bedroom)
- 70 dB: standard air conditioner (living room)
- 75 dB+: avoid at night
Criterion 4: Which Energy Class Should You Choose?
Energy class (A+, A, B, C…) indicates efficiency. Prioritize A+ or A minimum: you save 20-30% on electricity annually. An A+ air conditioner consumes ~500 kWh/year for 10,000 BTU; a C consumes 650. At 0.20 €/kWh, this represents 30 € annual savings. Over 5 years, this initial surcharge pays for itself.
Reading the Energy Label
The label displays the class (A+, A…), annual consumption (kWh), and SEER index (Seasonal Energy Efficiency Ratio). A SEER >5 indicates good efficiency. [Consult UFC-Que Choisir's guide on air conditioners](https://www.quechoisir.org/article-climatiseurs-mobiles-guide-achat) to compare models.
Criterion 5: What Type of Hot Air Evacuation?
Two systems dominate: window evacuation (single hose) and air-air (two hoses). Window evacuation is simpler, cheaper, but creates slight depression. Air-air captures outside air and rejects hot air outside: more efficient but bulkier. Verify your window allows hose passage (diameter 12-15 cm).
Advantages and Disadvantages
| Type | Advantages | Disadvantages |
|------|-----------|---------------|
| Single hose (window) | Simple installation, low price (200-400€) | Slight depression, less efficient |
| Air-air (two hoses) | Very efficient, no depression | Bulk, higher price (500-800€) |
Criterion 6: What Additional Functions Are Useful?
Dehumidification reduces ambient humidity (ideal on coasts or after rain). Scheduling allows starting the device before arrival. Night mode reduces noise. Remote control offers comfort. List your real needs: a family with children appreciates scheduling; a single person is satisfied with manual mode.
Recommended Functions by Profile
- Remote work: scheduling + silent mode
- Bedroom: dehumidification + night mode
- Family: scheduling + air filtration
Criterion 7: What Budget to Plan?
Portable air conditioners cost between 200 € (basic, 7,000 BTU) and 800 € (premium, 12,000 BTU with air-air). A mid-range model (9,000-10,000 BTU, A+ class, simple hose) sits around 400-500 €. Investing 100-150 € more for A+ class pays off in 3-4 years on electricity bills.
Indicative Price Grid
- 200-350 €: small model, B-C class, simple hose
- 350-550 €: standard model, A+ class, basic functions
- 550-800 €: high-end model, air-air, advanced scheduling
Criterion 8: What Manufacturer Warranty to Require?
A minimum 2-year warranty is standard. Some manufacturers offer 3 or 5 years. Warranty must cover the compressor (major part). Verify French customer service is accessible: intervention time, spare parts cost, filter availability. Aether Climate guarantees its models 3 years with spare parts available for 7 years.
Key Warranty Points
- Minimum duration: 2 years (3 years ideal)
- Compressor coverage: essential
- French customer service: <10 days response
- Spare parts: 5+ year availability
Final Checklist Before Purchase
- ☐ Room surface measured (m²)
- ☐ BTU calculated (35-45 BTU/m²)
- ☐ Noise level verified (<65 dB if bedroom)
- ☐ A+ energy class confirmed
- ☐ Evacuation type chosen (window or air-air)
- ☐ Functions listed (scheduling, dehumidification)
- ☐ Budget validated (200-800 €)
- ☐ Manufacturer warranty consulted (≥2 years)
With this checklist, you eliminate costly mistakes and select a portable air conditioner suited to your home and habits. Compare 2-3 models in your price range before concluding.
FAQ
How many BTU for a 15 m² bedroom?
For 15 m², count 525 to 675 BTU (35-45 BTU/m²). A 7,000 BTU air conditioner will suffice amply. Verify that the noise level does not exceed 65 dB for nighttime comfort.
Does a portable air conditioner consume a lot of electricity?
An A+ class 10,000 BTU air conditioner consumes approximately 500-550 kWh/year, or ~100 € annually at 0.20 €/kWh. A less efficient model (C class) consumes 30% more. Investment in A+ class pays off quickly.
What is the difference between a single hose and two hoses?
Single hose (window) evacuates hot air outside but creates slight depression. Two hoses (air-air) capture outside air and reject hot air: more efficient but bulkier and costly (100-200 € more).
Should you get a long warranty for a portable air conditioner?
A 2-year warranty is standard; 3 years is ideal. Most importantly, verify the compressor is covered and French customer service is accessible. Spare parts should remain available 5-7 years.
Can a portable air conditioner replace fixed air conditioning?
No. A portable air conditioner cools a single room effectively (15-30 m²). For an entire apartment, prefer a fixed split system. The portable remains a temporary solution or for a guest room.
Mots-clés : climatiseur mobile, climatisation, guide achat, bien-être, été