What does a fall furnace tune-up cover?
A furnace tune-up is mostly measuring things that are hard to judge by eye, then cleaning or adjusting what's out of spec. On a typical gas furnace, the technician:
- Pulls and cleans the flame sensor, then checks the flame signal once it's back in
- Tests the igniter and watches the full startup sequence for hesitation
- Listens to the inducer motor and checks the pressure switch hoses for cracks or water
- Measures gas pressure with a manometer and sets it to the manufacturer's spec
- Runs a combustion test and takes a carbon monoxide reading in the flue and around the furnace
- Inspects the heat exchanger and burners for cracks, rust and soot
- Checks blower motor amps, the run capacitor and the blower wheel for buildup
- Confirms the limit and rollout safety switches work
- Flushes the condensate trap on a high-efficiency furnace and checks the drain or pump
- Walks outside to look at the flue or PVC terminations
The point is to find the parts that are close to failing. A flame sensor running a weak signal in October is the no-heat call you'd otherwise get in January. Our fall furnace checklist lists what you can check yourself.
What does a spring AC tune-up cover?
Air conditioners fail in different ways, so the spring visit looks at different parts:
- Rinse the outdoor condenser coil from the inside out, after shutting off power at the disconnect
- Test the run capacitor against its rating and look over the contactor for pitting
- Check the refrigerant charge using superheat or subcooling readings, instead of topping off by guess
- Check the condenser fan motor and the electrical connections
- Clear the condensate drain line and check the pan under the indoor coil
- Look at the indoor coil for dirt that cuts airflow
A weak capacitor is one of the most common reasons an AC quits on the first hot week, and it's a quick test in April. For the full list, see our spring AC checklist. If something has already failed, AC repair starts with a service call, a $79 trip charge that's waived when you approve the repair.
Why do fall and spring tune-ups matter in Minnesota?
Timing is the whole idea. A furnace that sat all summer gets its first real test on the first cold night in October, which is when furnaces with a weak part tend to fail, all around the same week. A tune-up in September or early October finds that part while it's still an easy fix.
Spring works the same way for cooling. The outdoor coil spends June collecting cottonwood fluff, and a coil that's already dirty going into a humid July runs hot and hard.
A few things are specific to our winters. High-efficiency furnaces vent through PVC pipes that can frost over or get buried in drifting snow, so we check the terminations and tell you where to keep snow cleared. Whole-home humidifiers need a new water panel, and the setting should drop as it gets colder outside. And the outdoor AC unit is fine sitting uncovered all winter. Our post on covering your AC unit explains why a tarp causes more harm than good.
Heat pumps run in both seasons, so they get checked before each one. The fall visit adds the defrost cycle, the backup heat (electric strips, or the furnace on a dual-fuel system) and the outdoor temperature setting that decides when the backup takes over. Outside the gas lines, where a heat pump is often paired with a propane furnace, getting that handoff right shows up directly on the propane bill.
Filters: the maintenance you do yourself
The filter is the one part you handle between visits, and a clogged filter causes more furnace trouble than people expect. It starves the blower of air, the heat exchanger runs hot, and the limit switch starts shutting the burners off.
A standard 1-inch filter usually needs changing every one to three months. A 4- or 5-inch media filter usually lasts six months to a year. Very high-MERV 1-inch filters can restrict airflow on furnaces that weren't designed for them. If allergies are the reason for a better filter, a deeper media cabinet usually works better. Our filter guide covers MERV ratings.
How much does HVAC maintenance cost?
- Furnace tune-up: $129
- AC tune-up: $129
- Furnace and AC together: $219
- Other maintenance visits: $129–$349, with the price for your equipment confirmed when you book
Prices are the same in every town we serve, with nothing added for distance. Maintenance plans are available on request, so ask us about one when you book. If you're a Dakota Electric member, check its Energy Wise rebate list, which has included central AC and air-source heat pump tune-ups; funding is limited and terms change, so confirm before you book. If a tune-up turns up a failing part, you get a written, flat-rate repair price before we do anything, and completed repairs carry a 1-year parts-and-labor warranty. Property managers and businesses can set up scheduled visits through our commercial HVAC service. Call 612-429-3465 to book.
What's included with maintenance & tune-ups?
- Flame sensor cleaned, igniter and inducer tested
- Gas pressure and combustion checked, with a carbon monoxide reading
- Heat exchanger, flue and PVC vent terminations inspected
- Condensate trap and drain flushed on high-efficiency furnaces
- AC coil rinse, refrigerant charge check and capacitor test
- Filter checked, with the right size and change interval noted
- What we measured and what's wearing, explained before we leave
Maintenance & Tune-Ups questions
How often should I get my furnace tuned up?
Once a year, in fall, before the long run hours start. A Minnesota furnace runs from fall into spring, so wear adds up faster than in milder places. A yearly visit also leaves a service record, which helps if you ever need a warranty claim, since some manufacturers expect proof of regular maintenance. Heat pumps run in both seasons and should be checked before each one.
How often should I change my furnace filter?
A standard 1-inch filter usually needs changing every one to three months, more often with pets, remodeling dust or a furnace that runs hard in January. A 4- or 5-inch media filter usually lasts six months to a year. Check it monthly in winter. If it looks gray and packed, change it. Very high-MERV 1-inch filters can choke airflow on some furnaces.
Is a tune-up worth it on a newer furnace?
Yes. New condensing furnaces still have flame sensors that coat over, condensate traps that plug and PVC terminations that frost up in a cold snap. A first tune-up also lets us confirm the gas pressure and temperature rise were set correctly at install. Read your manufacturer's warranty terms too. Some require regular maintenance, so keep your receipts.
Should I cover my AC unit in winter?
Not with a plastic tarp. A cover that traps moisture can rust the cabinet and gives mice a warm place to nest, and the outdoor unit is built to sit in the weather. If you're worried about ice or icicles falling from the roof, a piece of plywood weighted on top is enough. Take it off before you turn the AC on in spring.
Do you do maintenance on boilers and heat pumps?
Yes. Boilers get their own checklist: system pressure, relief valve, expansion tank, circulators, the low-water cutoff on steam systems, and venting. Heat pumps get a heating-season check of the defrost cycle and backup heat, plus the usual cooling-season checks. Maintenance visits run $129–$349, and we confirm the price for your equipment when you book.
What can I do myself between visits?
Change the filter on schedule, keep grass clippings and plants away from the outdoor AC unit, and keep snow cleared from the PVC pipes of a high-efficiency furnace. Test your carbon monoxide alarms twice a year. Leave anything involving the gas valve, burners or electrical panels inside the furnace to a technician.