Filters and drains: the checks with a source
ENERGY STAR's maintenance advice is to change or clean filters monthly and to have a contractor do annual pre-season check-ups: cooling in spring and heating in fall. A heating check includes gas connections, gas pressure, burner combustion and the heat exchanger, and ENERGY STAR says a cracked heat exchanger can make the equipment operate less safely. Grand Rapids has about 6,408 heating degree days a year and Traverse City 7,104, so book the heating check first.
The same list includes the condensate drain in a central air conditioner, furnace or heat pump in cooling mode. ENERGY STAR says a plugged drain can cause water damage in the house. If the drain is the problem, AC repair covers the cooling side.
Indoor air quality costs in Michigan: permit fees and wages
Our estimate for this job in Michigan is $340 to $4,575 per installed system. It is a model, not a quote, built from one national published cost range, widened by 15 percent each side, and adjusted by Michigan's wage ratio to the US (1.00).
Our collection of the prices Michigan heating and cooling companies publish on their own sites is still under way; when it is large enough, the table will give the number of companies and the date we read them. Until then, the table holds what we can cite: wages, a duct sealing estimate and city permit fee lines for humidifiers.
| Item | Figure | What it is |
|---|---|---|
| Estimated range, not a quote | $340 to $4,575 per installed system | Built from one national published range, adjusted by the Michigan HVAC technician wage ratio (1.00). |
| HVAC mechanic and installer wage, Michigan mean | $31.01 an hour | What Michigan heating, air conditioning and refrigeration mechanics and installers are paid (BLS, May 2025), not what you are charged. |
| Sterling Heights permit line, humidifier | $29 | 2026-2027 mechanical form; the application fee is separate. |
| Westland permit line, humidifier, air cleaner or UV | $24 | Revised July 1, 2026; a $100 administration fee and minimum may apply. |
| Warren permit, furnace with humidifier or air cleaner | $80 combined | Form revised April 2023; one line covers the furnace and the add-on; confirm with the city. |
| ENERGY STAR duct sealing and insulating estimate | as much as 20 percent efficiency gain | An upper bound for efficiency, not a price or a health benefit. |
How we estimate costs: the figures here are estimates, not quotes, built from BLS wages, published city permit fees and federal energy-cost evidence. We are collecting the prices Michigan heating and cooling companies publish; we have not yet collected quotes from them, and we will say how many and from when once we do. Estimated range. Built from national published ranges (1 source), adjusted by Michigan's HVAC technician wage ratio to the US (1.00, BLS May 2025), plus the local permit fee where the city publishes one. Not a quote. We have too few Michigan company prices yet to show a range. Full method. Prices as of Oct 19, 2026.
Ducts: sealing is sourced, cleaning is not
ENERGY STAR says sealing and insulating ducts can improve the efficiency of a heating and cooling system by as much as 20 percent, and sometimes more. That figure is about efficiency, it is an upper bound, and it concerns sealing rather than cleaning. Older homes more often have older ductwork; in Detroit 90.1 percent of homes were built before 1980, which is a reason to have the ducts looked at and proves nothing about what is in them.
ENERGY STAR's 20 percent figure does not tell you whether duct cleaning helps air quality. Read the duct cleaning page and the duct cleaning cost guide before you agree to it.
Carbon monoxide and combustion air
The air problem with a source behind it is combustion. DTE says to hire a maintenance professional to check your furnace and fuel-burning appliances annually, to inspect flues so they are corrosion-free, securely attached and correctly vented, and to keep furnace room air vents unblocked. Michigan's Bureau of Fire Services advises an alarm on every floor, which is advice, not code. Ann Arbor has an ordinance requiring carbon monoxide detection in all rental properties. Our carbon monoxide guide has the details.
Where our sources stop
This page makes no claim about what whole-house air purifiers, UV lights or humidifiers do, and no health claim appears anywhere on this site. If a company says one will help, ask it to put the claim in writing and name its source. Ask what the equipment adds to the system, and who services it. A thermostat does not clean air either; see thermostat installation for the rebate side.
Air problems that cannot wait
- A carbon monoxide alarm is sounding.
- You smell gas.
- The furnace room smells of fumes or the flue has come loose.
- A dirty filter you can change yourself.
- Dust you want a company to look at.
What to do before you call anyone
- Check the filter and change it if it is dirty.
- Look at the condensate drain for a plug or standing water.
- Make sure vents and the furnace room are not blocked.
- Test your carbon monoxide alarms.
Permits and licensing for indoor air equipment in Michigan
Adding a humidifier or air cleaner to a furnace can fall under a city's mechanical permit, and the fee lines above show how three cities price it. Sterling Heights lists $29 for a humidifier, Westland lists $24 for a humidifier, air cleaner or UV unit, and Warren prices a furnace with a humidifier or air cleaner at $80 on one line. Those are the cities' own forms; ask yours. Mechanical work needs a mechanical contractor's license under Article 8 of 2016 PA 407, so ask for the license number and check it on LARA's lookup, and see the mechanical permit guide.
Ask for the license number and check it with your state's licensing board before any work starts. Our state pages link the lookup.
- Sterling Heights mechanical permit fee schedule Read Oct 19, 2026.
- Westland mechanical permit fee schedule Read Oct 19, 2026.
- Warren mechanical permit fee schedule Read Oct 19, 2026. Confirm with the source before you rely on it.
- MCL 339.5801 (Michigan Legislature) Read Oct 19, 2026.
- MCL 339.5809 Read Oct 19, 2026.
A tool for this job
Rebate and tax-credit finder
Pick your utility, your equipment and your household, and the finder shows each program's status with the date we checked it, October 19, 2026. Federal credits 25C and 25D ended for property placed in service after December 31, 2025, according to the IRS, even though ENERGY STAR's heat pump page still advertises one. It prints no amount without its program, tier and date.
Open the toolQuestions people ask
How often should I change my furnace filter?
ENERGY STAR says to change or clean filters monthly. Check the filter size and the arrow for airflow direction before you buy one.
Does duct cleaning improve indoor air quality?
ENERGY STAR's duct figure covers sealing and insulating and says nothing about cleaning, so this page makes no claim that cleaning helps. See our duct cleaning page for what to ask.
Do whole-house air purifiers or UV lights work?
No claim is made either way here. Ask the company for its source in writing.
Does a humidifier need a permit in Michigan?
Some cities list a fee for one on their mechanical permit form: Sterling Heights $29, Westland $24 for a humidifier, air cleaner or UV unit. Check your own city.
Where do I put carbon monoxide alarms?
Michigan's Bureau of Fire Services advises an alarm on every floor; DTE says near all sleeping areas. This is advice, not a statute we could cite. If one sounds, leave and call 911.
- U.S. Bureau of Labor Statistics, OEWS May 2025: heating, air conditioning and refrigeration mechanics and installers (SOC 49-9021), Michigan statewide Read Oct 19, 2026.
- ENERGY STAR Save at Home: Heat and Cool Efficiently; also /saveathome/heating-cooling/maintenance-checklist Read Oct 19, 2026.
- ENERGY STAR: Maintenance Checklist Read Oct 19, 2026.
- NCEI U.S. Climate Normals 1991-2020 annual/seasonal (data service) Read Oct 19, 2026.
- NCEI U.S. Climate Normals 1991-2020 annual/seasonal (data service) Read Oct 19, 2026.
- DTE Energy: Home Safety (gas) Read Oct 19, 2026.
- LARA BFS: Fire Safe Michigander Resources Read Oct 19, 2026.
- Rental Housing | City of Ann Arbor Read Oct 19, 2026.
- U.S. Census Bureau, American Community Survey 2023 five-year estimates (tables B01003, B25034, B25077) Read Oct 19, 2026.
- DTE Energy: Natural Gas Emergency Read Oct 19, 2026.
- HVACMatch: how we estimate costs (editorial policy) Read Oct 19, 2026.