How to Choose an Air Conditioner - Buyer's Guide

Cooling Capacity and Room Size

Cooling capacity is measured in BTU (British Thermal Units). You'll see numbers like 9,000 BTU or 12,000 BTU on Australian portable units. A 9,000 BTU unit cools a room about 20-30 square metres. A 12,000 BTU handles 30-40 square metres.

Measure your room carefully. An undersized unit won't cool effectively no matter how long it runs. An oversized unit wastes power and noise. Most Australian homes needing portable air con are cooling single rooms during summer, so 9,000-12,000 BTU is the sweet spot.

Keep in mind: sealing the room helps. If windows or doors leak air, the unit works harder and costs more to run. Portable air con isn't efficient for open-plan spaces.

Single Hose vs Dual Hose: Efficiency Matters

Single hose units pull air from inside the room, cool it, and exhaust hot air out a window hose. The problem: they create negative pressure, sucking warm air back in from gaps and cracks. Less efficient, noisier.

Dual hose systems pull outside air for cooling, exhaust hot air outside. Fewer efficiency losses, quieter operation, better cooling. More expensive upfront, but lower power bills over a summer.

For Australian summer heat (35+ degrees), dual hose is worth it. Single hose feels like a toy by comparison. Check your window space though, dual hose needs two hose penetrations.

Energy Rating and Running Costs

Australian portable air cons are rated with Energy Rating Labels. Look for the star rating. More stars = less power consumed. A 4-star unit costs noticeably less to run than a 2-star over a full summer.

Calculate the annual cost: check the kWh listed on the label, multiply by your local electricity rate. At 30c per kWh, a 12,000 BTU 4-star unit running 8 hours daily costs roughly $15-20 per month. A 2-star unit could be double that.

Summer heat means air con runs hard here. Spending $300 more on a high-efficiency unit saves $200+ over three summers.

Noise Levels: Don't Underestimate Bedroom Impact

Portable units are louder than split systems. Decibel ratings typically range 65-75 dB. That's as loud as a vacuum cleaner. Some models claim 60 dB, those are quieter, worth seeking out.

If you're cooling a bedroom, noise matters. You want something you can sleep near without hearing a constant hum. Brands like DeLonghi and LG have quieter models. Budget brands often skimp on sound dampening.

Run the unit before committing. Many retailers have display models you can hear. A cheap unit you can't sleep near isn't a bargain.

Window Installation and Australian Climate Considerations

Most portable units vent through windows via accordion hoses. Check your window type: casement windows work best. Sliding sash windows need adapters. Louvre windows are tricky. Know your setup before buying.

Australian humidity is brutal in summer, especially coastal areas and Queensland. Portable air con units dehumidify as they cool, which is good. They collect water in drain trays or condensate hoses. Check if your unit has a continuous drain option (connects to an outdoor drain) or if you're manually emptying trays.

Bushfire smoke is increasingly an issue. Portable units don't have genuine filtration. If you're in a fire zone and smoke events worry you, a split system with upgradeable filters is better long-term.

Australian Price Tiers

Budget: $500-800. Basic single hose, 9,000 BTU, low efficiency. Gets cold, but loud and expensive to run. Fine for occasional weekend cottage use.

Mid-range: $800-1,500. Dual hose options appear here. 12,000 BTU, decent energy rating. Better noise isolation. This is where most Australian households should buy.

Higher-end: $1,500-2,500. Premium models with quieter operation, better filters, smart control. Still portable, but built better.

Australian Consumer Law and Warranties

Portable air con units should reasonably last 3-5 years with proper maintenance. Consumer guarantees cover 2-3 years of reliable operation depending on price tier. Check manufacturer warranty, often just 1 year, but the law is stronger.

Common failures: compressor failures (around year 3-4), refrigerant leaks, and motor burnout. Ask retailers what local service options exist. Some brands have better Australian support than others. A cheaper unit with terrible local service might not be a bargain if it fails and can't be fixed locally.