An air conditioner is one of the few purchases where the installation matters more than the brand. A mid-range unit installed properly will outlast and out-cool a premium unit installed badly, every single time.
We know this because of what we get called out to. The majority of AC faults we attend in the first three years of a unit's life are not manufacturing defects. They are installation shortcuts coming home.
Sizing: Bigger Is Not Better
The most common mistake is buying an oversized unit on the theory that more capacity means colder rooms. It does not work that way.
An oversized unit cools the air quickly, hits the thermostat setpoint, and shuts off — before it has run long enough to pull the humidity out. You end up with a room that is cold and clammy, a compressor that short-cycles itself to an early death, and a higher bill than a correctly sized unit would have produced.
- Room dimensions and ceiling height
- How much direct sun the room takes, and when
- Number and size of windows, and whether they are shaded
- How many people typically occupy the room
- Heat-producing equipment — kitchen, office gear, TV
- Insulation and whether the roof space above is vented
Those are the factors that determine the right capacity. Anyone who quotes you a unit size without asking about at least half of them is guessing.
Inverter units cost more upfront and are worth it in almost every Jamaican home. Rather than switching fully on and off, they vary compressor speed to hold a steady temperature. That means less current draw, far less noise, and no cold-hot-cold cycling. On a unit that runs every night, the electricity saving typically pays the difference back well within the unit's life.
What A Proper Installation Actually Involves
Positioning the indoor unit
High on a wall, with clear airflow across the room and nothing blocking the return. Not directly over a bed where it blows on you all night, and not tucked into a corner where the air has nowhere to go.
Positioning the condenser
This is where most corners get cut. The outdoor unit needs genuine airflow around it — boxed into a tight space or pressed against a wall, it recirculates its own hot air and loses efficiency immediately. It should be shaded where possible, mounted on brackets fixed into solid structure rather than weak block, and on the coast, positioned to take as little salt spray as possible.
Vacuuming and pressure testing the lines
Before any refrigerant goes in, the line set must be pressure tested for leaks and then vacuumed to pull out air and moisture. This step takes time, which is exactly why rushed installers skip it. Moisture left in a refrigerant circuit combines with the oil and forms acid, which quietly destroys the compressor from the inside over a couple of years.
The condensate drain
The drain line must run with consistent fall all the way to its discharge point. If it sags, water pools, algae grows, the line blocks, and the indoor unit starts dripping onto your wall. This is the single most common AC callout there is, and it is entirely a function of how the line was run on installation day.
The electrical supply
An air conditioner deserves its own dedicated circuit with a correctly rated breaker — not a spur off the nearest lighting circuit. We handle this as part of the same job with our electrical team, so there is no gap between two contractors each assuming the other did it.
Questions To Ask Before You Book Anyone
- How did you arrive at that unit size for my room?
- Will you vacuum and pressure test the lines before charging?
- Where exactly will the condenser sit, and why there?
- Where does the condensate drain discharge?
- Is there a dedicated circuit, or are you using an existing one?
- What warranty covers the unit, and what covers your labour?
Any competent installer will answer all six without hesitating. If the answers get vague, that tells you what you need to know.
Need Air Conditioning Done Properly?
NASTIC covers air conditioning for homes and businesses across all 14 parishes, with written quotes before we start and our workmanship guarantee behind every job.