Heating and cooling in Farmington
Furnace age matters in Farmington, and the Detroit Metro airport normals, which we use as the nearest station, show why heat comes first: about 6,067 heating degree days a year (base 65 F). Of the homes, 74.6 percent were built before 1980, against 53.7 percent in neighboring Farmington Hills, 1.7 miles away, and the median value is $273,000. Two addresses a short drive apart can have very different ductwork and furnace ages.
The permit office is Farmington Planning and Building, 33720 W. Nine Mile Road, open Monday to Friday 8:30 a.m. to 4:30 p.m., phone 248-473-7250. Online permitting is linked from the department's page. Ask your company whether it files the mechanical permit online, and ask for the permit number once it is issued. If you replace a furnace yourself in a home you own and live in, state law lets owners do it with a permit and an inspection, and the inspection comes after the equipment is running.
The wider area: Southeast Michigan
Southeast Michigan is the state's largest furnace market, and Detroit Metro airport averages about 6,067 heating degree days and about 847 cooling degree days a year (NOAA 1991 to 2020 normals, base 65 F). The Ann Arbor station reads higher, at about 6,501 heating degree days, so a house in Washtenaw County heats a little longer than one in Wayne. The DOE and PNNL county table puts Wayne, Oakland, Macomb and Washtenaw counties in IECC climate zone 5. The cities we researched here, including Detroit, Warren, Sterling Heights and Ann Arbor, enforce the mechanical code locally. As of Oct 19, 2026, MiHER's income-qualified applications are suspended in the Detroit and Warren districts, and Ann Arbor residents can look at the city's A2ZERO heat pump rebate.
What heating and cooling work costs near Farmington
We have collected no quotes for Farmington, so there is no price for the city itself. The statewide estimates are on each service page, and the Michigan page shows what technicians are paid (the Michigan mean in BLS data for May 2025 is $31.01 an hour, which is pay, not price) and the permit fees we could read. How we estimate costs.
Permits for heating and cooling work in Farmington
Mechanical work may not start until a permit is issued, except replacement of minor parts. A furnace, central air conditioner or heat pump replacement is not on LARA's exemption list, which is our inference from the list, not a sentence LARA wrote. Read the permit guide
Heating and cooling jobs in Farmington
The short answer to each job, as it applies across Michigan. Each links to the full page with the cost evidence, permit rules and what to try first.
- Furnace repairFurnace repair starts with two free checks, the thermostat setting and the filter. If you smell gas or a carbon monoxide alarm sounds, leave the house and call 911 and your gas utility before anything else.
- Emergency HVACFor emergency HVAC repair, the first call depends on what you notice. A gas smell or a sounding carbon monoxide alarm means leaving the building and calling 911 and your gas utility, not a repair company.
- Furnace replacementFurnace replacement in Michigan involves choosing an efficiency level, a mechanical permit and a company with the right license. ENERGY STAR's specification for the northern U.S., which includes Michigan, is 97% AFUE, against a federal floor of 80%.
- Boiler repairBoiler repair in Michigan falls under mechanical contractor licensing, which is separate from plumbing licensing. For steam or vapor boilers up to 15 psig in a private residence, LARA says the permit must be secured by a licensed mechanical contractor in the hydronic heating and cooling and process piping classification.
- Heat pump installationHeat pump installation in Michigan comes down to choosing a model tested for cold weather and checking which rebates still have money. ENERGY STAR cold climate heat pumps are tested down to 5 F, and ENERGY STAR advises a back-up energy source at lower temperatures.
- AC repairAC repair in Michigan starts with checks you can do yourself: the filter, the thermostat setting, the breaker and any water near the indoor unit. Refrigerant is different, because under EPA Section 608 only certified technicians may buy refrigerant for stationary air conditioning, so a top-up is not a do-it-yourself job.
- AC installationAC installation in Michigan needs a mechanical permit, a size worked out from your house rather than from the old unit, and an efficiency rating of at least 13.4 SEER2 for a split system.
- Mini-split installationMini split installation adds a ductless heat pump to a house without running new ducts, and in Michigan the first question is how it will heat in January. ENERGY STAR says certified mini splits use up to 60% less energy than standard home electric radiators; that compares them with electric resistance heat and says nothing about a gas furnace.
- Duct cleaningWe found no government source on the benefits of duct cleaning, so this page makes no claim for it. The federal evidence we did find is about sealing and insulating ducts: ENERGY STAR says doing so can improve the efficiency of a heating and cooling system by as much as 20 percent.
- Thermostat installationThermostat installation is the smallest job in this trade, and in Michigan the rebate matters more than the labor. DTE offers $50 for a Wi-Fi thermostat, one per household, with applications due within six months of purchase and no later than December 31, 2026.
- Indoor air qualityIndoor air quality work on a heating and cooling system starts with the dull items: the filter, the condensate drain and leaky ducts. ENERGY STAR says to change or clean filters monthly and to have a contractor check the system before each season.
More on Michigan heating and cooling
Licensing, permits and the mechanical code are covered once for the whole state on the Michigan page. To check an HVAC contractor, read how to find a licensed HVAC contractor in Michigan.