A year built around summer
Lake Havasu City drew the world's attention in 1968 when McCulloch bought the London Bridge, which was taken apart in London, shipped here and rebuilt over three years beside a dredged channel. The city was incorporated in 1978 as a recreation and retirement community. Whatever brought you here, the heating and cooling year runs on a simple rhythm: a long, demanding cooling season, a short, gentle heating season, and two shoulder periods for maintenance. This checklist follows that rhythm.
Late winter: plan ahead
- Look at the system's age and history. If it struggled last summer, this is the time to get quotes, before every installer's calendar fills.
- Ask for a load calculation if you are replacing equipment, so the size is chosen for the house rather than copied from the old unit.
- Know the efficiency floor. Arizona is in the Department of Energy's hot-dry Southwest region, where split-system central air conditioners installed on or after January 1, 2023 must meet at least 14.3 SEER2 (13.8 SEER2 for 45,000 Btu/h and larger) and also a minimum EER2 of 11.7 (11.2 for the larger units) when rated below 15.2 SEER2, or 9.8 when rated at 15.2 SEER2 or higher. Ask for both ratings on any matched system you are offered.
Spring: the pre-summer tune-up
- Clean the outdoor coil. Dust and pollen coat the fins and cut airflow.
- Check the refrigerant charge and the electrical parts, such as the capacitor and contactor, which tend to fail under heat.
- Clear the condensate drain and check the safety switch, so a clog can't overflow into a ceiling.
- Replace the filter and note the size and rating on the frame for next time.
- Walk the attic if you can do it safely, looking for crushed, torn or disconnected ducts.
Summer: keep it running
- Change filters more often than the label says if dust or pets are part of the house.
- Keep the outdoor unit clear of plants, stored items and windblown debris.
- Watch for warning signs: longer run times, warm air from some vents, ice on the copper line, water near the indoor unit, or a breaker that trips.
- Use the thermostat steadily. Large setbacks on very hot days can leave a system unable to catch up by evening.
Water-fed equipment and hard water
Lake Havasu City's 2025 water report lists total hardness averaging 19 grains per gallon (range 18 to 20), from calcium and magnesium that occur naturally in the source. Scale builds wherever that water evaporates. If you use an evaporative cooler, a whole-house humidifier or a misting system:
- inspect pads and media monthly during use, and replace them when they crust over;
- check that the bleed-off or drain line is working so minerals don't concentrate;
- clean the reservoir and float valve on a regular schedule;
- ask the installer whether water treatment would extend the life of the equipment.
Fall: switch to heat
- Test the heat on a cool morning before you need it, so a problem shows up early.
- For heat pumps, listen for the defrost cycle and confirm backup heat comes on when called.
- For gas furnaces, have the burners, flue and safety controls checked, and test carbon monoxide alarms.
- Seal and insulate any ducts you found damaged in spring.
Before you sign for a new system
- Get the outdoor and indoor model numbers, and the matched SEER2 and EER2, in writing.
- Ask what the load calculation showed and how the tonnage follows from it.
- Ask whether duct testing and sealing are included.
- Ask who pulls any permit and arranges inspection.
- Get labor and equipment warranty terms on paper, and ask who answers the phone if the system fails in its first July.
Keep a record
Write the filter size, service dates and any repairs on a card taped near the air handler, or keep them in one folder. The next technician, or the next owner, will be glad of it.