Season-by-season checklists, filter guidance, and the small habits that keep equipment running for 20 years.
A real furnace tune-up covers combustion safety and performance, not just a filter swap. It includes a carbon monoxide test, heat exchanger inspection, flame sensor cleaning, inducer and pressure switch check, gas pressure and temperature rise measurement, blower amp draw, condensate drain clearing on 90%+ units, and a thermostat cycle test. Expect 45 to 90 minutes.
A complete AC tune-up includes washing the outdoor coil, testing the capacitor against its microfarad rating, checking refrigerant charge by superheat or subcooling rather than just pressure, measuring the temperature split across the indoor coil (16 to 22°F is normal), clearing the condensate drain, inspecting the contactor, and recording compressor and fan amp draws. Plan on about an hour.
In Southeast Michigan, change a standard 1-inch pleated furnace filter every 60 to 90 days, and a 4- or 5-inch media filter every 6 to 12 months. Cut those intervals in half if you have shedding pets, a dusty basement, or a remodel underway. Check it monthly in January and July, when the system runs the hardest.
Buy the filter size printed on the old filter's frame, which is the nominal size; the actual size runs about a quarter to half inch smaller. For most Southeast Michigan homes, MERV 8 to 11 is the right range for a 1-inch filter. MERV 13 belongs in a 4- or 5-inch media cabinet, where the extra pleat depth keeps airflow from suffering.
Prepare a Michigan furnace in October, not December: run a test heat cycle on a mild day, install a fresh filter, clear the PVC vents and chimney cap, replace CO alarm batteries, open the humidifier damper and set it to 30 to 40 percent, and book a professional tune-up before the first sustained cold. Keep the furnace area clear and know where the gas shutoff is.
Get a Michigan air conditioner ready in late April or May: remove any cover, clear two feet around the condenser, rinse the coil gently, install a new filter, flush the condensate drain, confirm the disconnect is in, and run a 20-minute test on a day above 65°F. If the air is not noticeably cold or the outdoor fan is not spinning, schedule service before June.
Flush a tank water heater once a year to clear sediment, and check the sacrificial anode rod every 3 to 5 years, replacing it when it is mostly bare wire. In Southeast Michigan's hard water, those two steps are the difference between a tank that lasts 8 years and one that lasts 15. Test the temperature and pressure relief valve at the same time.
Replace a whole-home humidifier's water panel every fall, clean the distribution tray and drain, check the solenoid valve and orifice for mineral buildup, open the bypass damper for winter and close it in spring. Set the humidistat for 30 to 45 percent and lower it when outdoor temperatures drop below 10°F so windows do not frost.
Call or text and you reach Al, not a call center. Same-day service whenever possible, flat-rate pricing quoted before any work, and the same rate at 2 a.m. as 2 p.m.
