AC Maintenance Checklist

A short list of regular checks keeps an air conditioner running efficiently and helps you notice trouble before the first 100 degree day. Some items are for homeowners, and some belong to a licensed technician. This checklist separates the two.

Check the airflow

Hold your hand over a few supply vents while the system is running. Air should come out steadily and feel noticeably cool. Weak airflow from one room or the whole house suggests a clogged filter, a blocked duct or a blower problem. Make sure furniture, drapes and rugs are not covering vents or return grilles.

Change the filter

A dirty filter is the most common cause of poor cooling and of many other problems, including frozen coils. Replace a 1 inch filter every one to three months during cooling season, and more often if you have pets or if wildfire smoke or dust is hanging in the valley. Write the date on the frame so you do not have to guess.

Use your senses

Walk around the indoor and outdoor units while the system runs and pay attention. Listen for grinding, squealing, rattling or banging. Notice any burning smell, musty odour or sharp chemical scent. A change in how the system sounds or smells is often the first hint of a problem, and it is worth acting on early.

Look at the outdoor unit

Turn the power off at the disconnect before working close to the unit, and never open its panels. Clear leaves, grass clippings, cottonwood fluff and weeds from around the cabinet, leaving a foot or two of open space. Rinse the outside fins gently with a garden hose if they look dusty, spraying from the outside in at low pressure. Bent fins can be straightened by a technician.

Watch for ice or water

Look at the refrigerant lines and the indoor coil area for ice or frost. Ice means something is wrong with airflow or refrigerant, and you should turn the cooling off, run the fan to thaw it and call for service if it returns. Also check for puddles near the indoor unit, which can mean a blocked condensate drain.

Check the thermostat

Make sure the display is working, the batteries are fresh and the schedule matches your routine. Confirm that the system starts when you lower the setting and stops when the room reaches temperature. A thermostat in direct sun or beside a vent will misread the room.

If you have a programmable model, check that the day and time are correct after any power outage, because a schedule that is off by a few hours can leave the house warm when you want it cool.

Leave these to a technician

Several items matter a great deal and are not homeowner jobs:

• Measuring and adjusting refrigerant levels, which also means finding and repairing leaks.
• Inspecting electrical connections, capacitors, contactors and the compressor.
• Cleaning the indoor coil and the blower assembly.
• Flushing the condensate drain and checking the pan.
• Measuring temperature drop across the coil and confirming the system is delivering its rated performance.

Refrigerant and electrical work require licensing and training, and doing them yourself can be dangerous.

A tune-up is also the right time to raise anything you have noticed during the season, such as a room that never gets cool or a noise that comes and goes. Keep a short note on your phone of what you saw and when, since that helps a technician narrow down a problem that is not happening at the moment of the visit.

Put it on the calendar

Spring is the best time for a professional check, before the heat sets in. If you want the schedule taken care of, Air-Tech's AT Advantage Program includes two visits a year, covering both cooling and heating. Call (509) 392-2021 and we will help you get your air conditioner ready for summer.