Late winter to early spring. February through April, before the first genuinely hot week. Every year a lot of people find out the hard way why that window matters.
In a mild climate, a system that fails in July is uncomfortable. In Tucson it's a different category of problem, and everybody discovers their system is broken in the same week — the first stretch that climbs past 100.
That's when every HVAC company in the city is booked solid, parts move fastest, and you have the least leverage over timing. A tune-up in March costs the same as a tune-up in July and is worth considerably more.
Refrigerant pressures read and compared against what the system should be doing, not just topped up. Electrical components tested under load, because a capacitor that reads fine cold can fail hot. Condenser coil cleaned, which in this climate matters more than almost anything else on the list.
Condensate line cleared before it backs up. Blower and filter checked. Temperature split measured across the coil, which is the number that tells you whether the system is actually performing or just running.
That last one is worth asking about. A system can run all day and still not be cooling properly, and the split is how you know.
Furnaces sit unused for most of the year here, which is exactly why the first cold night produces a wave of no-heat calls. October or November is the window.
A heating check also catches the safety items — a cracked heat exchanger, a failing flame sensor, a limit switch that's been tripping — and those are worth finding when it's optional rather than at 2am in January.
Not immortality. A well-maintained system still fails eventually. What it buys is that failures get caught while they're small, that the system holds its efficiency instead of quietly costing more every year, and that you're not competing for a technician during the worst week of the year.
It also protects the warranty. Most equipment warranties expect documented maintenance, and a claim on a system that's never been serviced can get complicated.
Call or text and we'll get you on the schedule while there's still room in it.
