HVAC Installation in Miles City, MT
A new system here will heat from September through May and cool from June through August every year. Tell us about the house, and a licensed contractor who covers Custer County will get in touch.
Tell us about the job
It takes about a minute.
What a system here has to handle
Winter nights in Custer County average 11°F from December through February, and homes need heat from September through May. That's nine months of the year the furnace has to work. Summer asks less of it, just June through August, with afternoons averaging 84°F. Add the two together and something in the house is running nearly all year.
Most homes here heat with gas, and a new furnace has to be sized for those 11°F nights, not the milder days around them. The air conditioner has fewer months to prove itself, but it still has to hold up through those summer afternoons. Custer County has seen 17 winter storms and 94 damaging wind events over the past ten years, and across Montana, 18% of households went at least 24 hours without power in 2024. Whatever gets installed should come back on by itself once the power does.
- 9 months
- September through May, your system heats
- 3 months
- June through August, it cools
- 11°F
- the average winter night it heats against
- 84°F
- the average summer afternoon it cools against
NOAA nClimDiv, 1991–2020 normals
Montana requires HVAC contractors to hold a state license.
The state tests and licenses the contractor, not each job. That license is on file with the Department of Labor and Industry and follows the business, so the same license covers this installation and every other job that contractor takes on. Work under $2,500 is the one carve-out Montana makes, and a full system installation runs well past that.
For a job this size, the license is what stands behind the person in your house. On top of that, most cities and counties in Montana require a permit for a furnace, air conditioner or heat pump installation, with an inspection once the work is done. That inspection is what checks the gas connections, the wiring and the venting after the fact, separate from anything the license covers.
Source: Montana Legislature
- When should I replace my HVAC system?
- Replace it when repairs stop making sense or the system can't keep up anymore. If your furnace is breaking down every winter, or a repair bill is running close to what a new unit would cost, that's your answer. Age matters too. A furnace working hard nine months a year here, from September through May, wears faster than one in a milder climate, so don't be surprised if yours needs replacing sooner than the number on the brochure suggests. If the house won't hold heat when it's 11°F outside, waiting only risks a breakdown on the coldest night of the year.
- Should I replace my furnace and air conditioner at the same time?
- If both are old, replacing them together is usually the better move, but it isn't required. A furnace and air conditioner installed as a matched pair tend to run more efficiently and cause fewer service calls down the road than two units of different ages paired up after the fact. Here, the furnace does most of the heavy work, nine months of heating against three months of cooling, so if only one system is failing, it's fair to ask a contractor whether the other one has enough life left to wait. They can look at both and tell you honestly.
- What happens during an HVAC installation?
- A contractor removes the old furnace and air conditioner, sets the new equipment in place, and connects it to your ductwork, gas line or electrical circuit, and thermostat. They'll check the ducts for leaks or sizing problems while they're in there, since a new system connected to bad ductwork won't perform the way it should. Once it's running, they test airflow, check refrigerant levels on the AC side, and confirm the furnace is firing correctly. Montana requires HVAC contractors to hold a state license for this work, and most cities and counties also require a permit and inspection when a furnace or air conditioner is replaced, so ask your contractor how that's handled before work starts.