Air conditioner maintenance: how often, what it includes and what it costs

An air conditioner that runs most days of the year in heat, humidity and dust gets dirty fast. Dirty, it cools less, uses more electricity and ends up dripping or breaking down. This guide covers what you can do yourself, how often to call a technician, and what a service visit should include to be worth paying for.

What you can do yourself

• Clean the filters. They are the mesh screens behind the front cover of the indoor unit. Take them out, wash them with water, let them dry in the shade and put them back. If you use the unit daily, do it every two to four weeks.
• Keep the outdoor unit clear. No leaves, boxes or plants up against it: it needs air to move through.
• Watch the drain. The pipe that carries the water away should drip outside while the unit is running. If it stops dripping and water appears indoors, it's blocked.

Everything else — opening the unit, washing the coils, checking the gas, the electrics — is a technician's job.

How often to call a technician

These are rules of thumb: your unit's manual and the technician who sees inside it have the last word. On the coast, salt air is what matters — it corrodes the coil of the outdoor unit. Rinsing it with fresh water now and then, and having it checked more often, makes it last longer.

What a service should include

Ask beforehand exactly what they do. A full service on a split unit includes:

• Washing the filters, coil and fan wheel of the indoor unit.
• Cleaning the drain pan and drain pipe.
• Washing the coil of the outdoor unit.
• Checking the refrigerant pressure — without topping up as a matter of routine.
• Checking electrical connections, the capacitor and current draw.
• A final test: it cools, it drains, and it doesn't rattle or hum.

If the visit takes ten minutes and they only shake out the filters, that wasn't a service.

What it costs, as a guide

These are prices some companies publish on their websites, checked in October 2026. Use them to tell whether a quote is in the normal range, not as a tariff: each company sets its own, and it changes with the area, the height and the type of unit.

For installation, that price covers labour and, depending on the company, basic materials. Extra piping, a 220 V breaker, special brackets and building work are quoted separately. Ask whether the price includes IVA (sales tax) and whether there is a travel charge outside the Central Valley.

Signs it can't wait

• It barely cools, or takes a long time to.
• Water drips inside the house.
• Ice forms on the pipes or the indoor unit.
• It smells damp when you switch it on.
• New noises, or the breaker trips.
• The electricity bill goes up with no change in how you use it.

What to ask before you hire

• What does the service include, and how long does it take per unit?
• Is the price per unit? Does it change with capacity (BTU) or how high the unit is mounted?
• Do you charge for the visit if it turns out to need a repair?
• Is there a written guarantee on the repair or installation?
• Do you give an invoice (factura)? You can check the business exists with the tax authority: see how to do it.

With several units in one house, ask for a price for the lot: nearly every technician gives a discount. And get more than one quote: see how to compare them.