A SAR 120 AC installation is the most expensive thing you can do. Here's why — and what a proper one actually looks like.

The three things that matter — none of which the showroom mentions

When you buy a split AC from a retailer in Riyadh, the conversation is about BTU capacity, energy rating, and which brand has the better remote. What nobody discusses is pipe flaring quality, the vacuum step, and drainage slope. Those three things determine whether your SAR 3,000 AC runs efficiently in year 8 or needs a SAR 1,500 compressor in year 3.

Indoor unit placement

Height: The bottom of the indoor unit should sit 15–20cm from the ceiling — high enough for cold air to fall and circulate, low enough to be accessible for filter cleaning. In Riyadh you'll be cleaning that filter every 3–4 weeks; if the unit is too high you'll be standing on furniture every time.

Position in the room: The cold air should blow across the room's main occupied area, not directly onto where people sleep or sit. Direct cold airflow onto sleeping people is a common complaint in Hittin bedrooms where the AC was placed directly above the bed. In a rectangular room, placing the unit on a short wall so it blows the length of the room gives the best distribution.

Exterior wall preferred: Shorter pipe run to the outdoor unit, less heat gain along the refrigerant line, lower installation cost, fewer leak opportunities. Interior wall installations are possible but the pipe routing deserves careful thought.

Outdoor unit placement

Clearance is not optional: Minimum 50cm on all sides, 1.5m in front where hot air discharges, 1m above if there's an overhang. The outdoor unit needs to pull fresh air in from the back and discharge hot air from the front. Block either and the compressor overheats. I've seen outdoor units in enclosed utility areas in Hittin villas where the same hot air was recirculating — the AC was trying to cool a room using air that was already 60°C.

Shade reduces compressor stress: An outdoor unit in direct Riyadh summer sun can reach 70–75°C on its metal casing. A shaded location — north-facing wall, under an existing roof overhang — can be 15–20°C cooler. That's a meaningful reduction in compressor operating temperature and real extension of compressor lifespan.

The vacuum step — what cheap installers skip

Before any refrigerant gas is added to a newly installed AC, the entire circuit must be evacuated with a vacuum pump. This removes: the nitrogen used to pressure-test pipes during shipping, any atmospheric air that entered during installation, and any moisture.

Why moisture matters: At the expansion valve, the refrigerant gets extremely cold during rapid pressure drop. Moisture in the system freezes at that point, blocking the expansion valve and eventually destroying it.

Why air matters: Oxygen in a refrigerant circuit causes slow oxidation of the compressor oil and internal surfaces. Over 3–5 years, this accelerates compressor wear and failure.

A proper vacuum takes 20–30 minutes minimum. After vacuuming, the system is sealed and the vacuum held for 15 minutes to confirm no leak. This entire process takes 35–50 minutes. Anyone completing a full split AC installation in under 90 minutes has skipped the vacuum. No exceptions — the physics don't compress below about 20 minutes even with good equipment.

Pipe flaring — the second most important thing cheap installers rush

The copper refrigerant pipes need to be cut and have their ends "flared" — formed into a precise bell shape — to create a leak-free seal at the connection points on the AC unit. Poor flaring is the most common cause of early gas leaks in newly installed ACs in Riyadh.

Good flaring requires: a sharp clean pipe cutter (dull = burrs = leak points), a quality flaring tool, correct technique (the flare must be even, at the right angle, with no cracks), and careful connection with the correct torque. A rushed flare creates a micro-leak that may not show immediately but develops over months. By the time the customer notices weak cooling, the gas has been slowly escaping for 6–12 months.

Drainage slope — the third thing that goes wrong

The indoor unit produces condensate water that drains through a condensate pipe to the outside. That pipe must slope consistently downward — no flat sections, no dips where water can pool. Even a small flat section accumulates standing water, breeds mold, and eventually blocks the drain entirely. A blocked condensate drain backs water up into the unit, which then drips from the indoor unit's front panel. In an Al Nakheel villa I serviced last summer, the customer had a persistent water stain under the AC — a condensate drain that had been slightly uphill at one section since installation 3 years earlier.