ac maintenancein city walk.

The shamal is the north-westerly wind that pushes fine desert dust across the Gulf, most aggressively from late May through August. Its particles are far finer than household dust — fine enough to pass cheap mesh filters and coat the evaporator coil itself. In a bad shamal week, a filter that normally lasts two months loads up in a fortnight, and homes near construction sites see the same effect year-round. The filter is the cheapest part in the system and the cause of the most expensive failures: a blocked one cuts airflow, triggers icing, strains the blower and inflates bills before anything visibly breaks. Washing your return-grille filters monthly in summer is the highest-value maintenance act available to you, and it is free.

What you cannot do yourself is clean what got past the filter. Fine dust bonded to a damp coil turns into a felt-like mat a hose will not shift; it needs a chemical foam wash and, for ducted units, access panels opened above the ceiling. If filters look clean but airflow stays weak and bills creep up, the coil and blower wheel are the usual suspects.

Refrigerant is not fuel. It circulates in a sealed loop and is never consumed, so a unit that needs gas has a leak — full stop. The honest version of a regas visit: find the leak with a detector or nitrogen pressure test, repair it, pull a vacuum on the lines, then weigh in the exact charge printed on the nameplate. The dishonest version is a hose, a cylinder, and see-you-next-summer. If you have paid for top-ups two years running, you have paid twice for one unfixed leak.

The gas itself matters. Older UAE units run R22 — the gas everyone still calls freon — which is being phased out under the Montreal Protocol; imports are restricted and the shrinking supply gets pricier every year, so regassing an old R22 unit can cost a startling share of its remaining value. Most systems from the last decade use R410A, and newer machines increasingly use R32, more efficient but mildly flammable. The gases are not interchangeable: R410A runs at much higher pressures than R22, so you cannot refill an old system with new gas. When a technician says an ageing R22 unit with a leaking coil is not worth repairing, the arithmetic usually supports them.

Split units in the UAE live hard lives — near-continuous summer duty, corrosive coastal air, dust — and ten to fifteen years is realistic, with the coast taking the lower end as salt eats condenser fins. When a major component fails, run the arithmetic: a compressor replacement on an out-of-warranty unit frequently lands within reach of a new mid-range split once gas and labour are priced in, and on an R22 unit the scales tip harder toward replacement because every future leak inherits the rising cost of a phased-out gas. Efficiency compounds the case: a modern inverter split modulates its compressor instead of slamming on and off, and against a ten-year-old fixed-speed unit the difference shows directly on a DEWA, SEWA, ADDC or EtihadWE bill through six months of heavy duty.

The rule of thumb technicians use among themselves: if the repair costs more than about half the price of an equivalent new unit and the machine is past eight years old, replace it. Below that line, repair and keep maintaining. Decide unit by unit — a villa's five condensers rarely fail on the same schedule, and replacing each as it crosses the line spreads the cost across several summers.