The short answer: in Alaska, “turning the heat off” isn’t really an event. July is the closest thing the state gets to a lull, and even then the furnace or boiler is still doing some work most mornings. Cooling, on the other hand, is barely part of the picture at all, which changes what a seasonal changeover even means here.
The quietest month in Alaska
At Anchorage’s reference station, July comes out as the calmest month of the year, with heating and cooling demand together adding up to about 178 degree days. Compare that to the rest of the country: the lowest quietest-month figure anywhere in the fifty states runs around 70, and the highest hits about 246. Alaska’s July sits closer to the middle of that range than to the bottom, which already tells you something: this isn’t a state where the house goes silent in summer.
Degree days measure demand, not temperature. Each one reflects how far the day’s average temperature sits from a 65°F comfort baseline, added up over the month. A high number means the house is asking for a lot of heating or cooling work; it says nothing about how warm or cold it actually felt outside on any single day.
So is July a real pause, or just the year’s quietest changeover? Here’s the honest answer: it’s not a pause. Anchorage’s mean temperature stays below that 65°F baseline in every single month of the year, including July, its warmest month at just 59.6°F. That means heating demand never fully disappears. The house isn’t asking for nothing in July, it’s asking for less. Some mornings still call for heat even at the height of summer, while cooling demand barely registers at all through the year. No month here carries enough of both heating and cooling load to count as a true crossover month.
That’s a very different shape than a lot of the country sees. In states where summer brings genuine heat, the furnace goes fully dormant for weeks while the air conditioner takes over. In Alaska, the heating system just eases off its workload before picking it back up, and the air conditioner, where one even exists, barely gets used regardless of the calendar.
Shutting the heat down for the year
Because Alaska’s heating demand never actually reaches zero, this isn’t a true shutdown the way it would be in a warmer state. It’s a seasonal ease-off, best timed around July, and it should never mean disconnecting the system entirely, since the risk of frozen plumbing is real in a climate that never leaves heating season behind. Here’s the order that makes sense:
- Turn the thermostat setpoint down rather than cutting the system’s power. The system may still need to cycle on some cool mornings, even in midsummer.
- Let any active heating cycle finish on its own before doing anything else to the equipment.
- If the system burns fuel, natural gas heats 57% of homes here and fuel oil or kerosene another 24%, follow the manufacturer’s guidance for seasonal fuel-burning checks. Don’t shut off the gas supply or extinguish a pilot light yourself; that’s a job for the equipment’s own service checklist.
- Inspect, clean, or change air filters. ENERGY STAR’s standing advice: “Inspect, clean, or change air filters once a month in your central air conditioner, furnace, and/or heat pump.” That covers all three pieces of equipment, not furnaces alone.
- Shut down any humidifier mounted on the ductwork. It’s tied to the heating system and almost everyone forgets it exists once the furnace quiets down.
- Clear registers, vents, and the area around the equipment closet of dust and clutter while the system is running light.
One local wrinkle worth flagging: 36% of Alaska homes heat with a steam or hot-water boiler, alongside 37% on a furnace. Boiler households don’t have a filter to change in the same sense; their seasonal check is bleeding radiators and confirming system pressure instead, a different short list from the furnace one above.
The first run of the cooling season
If cooling exists in your home at all, test it on a mild day, not the first hot one. A mild day gives you room to catch a problem and fix it before you actually need the system to work.
But in Alaska, that test applies to a small slice of households. Only about 7% of homes here report having any air conditioning at all, and central air is such a small share of that it’s too rare to publish a separate figure for. Most of the air conditioning that does exist runs through individual equipment, window units, wall units, or ductless mini-splits, accounting for roughly 6% of homes. Ceiling fans are far more common, found in 46% of homes, and for most Alaskans that’s the actual summer cooling strategy.
For the households that do run cooling equipment, the checklist still holds:
- Clear debris and growth from around any outdoor unit, if one exists.
- Check that the condensate drain path is clear, for central or mini-split systems.
- Change or wash the filter, whether it’s a central system’s filter or the one built into a window unit or mini-split head.
- Run the system in COOL for a full cycle on a mild day, not the first heat wave.
- Feel the air at the farthest register or vent from the unit, not just the nearest one.
ENERGY STAR’s line on filters applies just as much here: “Airflow problems can reduce your system’s efficiency by up to 15 percent.” A window unit with a clogged filter can be running fine mechanically and still underperforming badly. With reference-station data showing zero days a year reaching 90°F or higher, the actual cooling load most Alaska homes face is modest to begin with, which is exactly why fans handle so much of the job here.
The days that ask for both
Some houses call for heat at six in the morning and want cooling by mid-afternoon, all in the same week. It’s a real pattern in a lot of the country. In Alaska, though, it barely shows up.
Using the convention applied across this site, a month counts as demanding both when it carries at least 50 heating degree days and at least 50 cooling degree days in the same month, a threshold stated here for comparison, not one NOAA itself publishes. By that measure, no month in Alaska qualifies. Even July, the peak for cooling demand, adds up to only about 5 cooling degree days against 174 for heating. The two demands never really compete on the calendar here.
That doesn’t mean a single day can’t feel like both. A cool morning followed by a mild, sunny afternoon happens regularly in summer, it’s just rarely intense enough to justify running a cooling system at all.
| Setting | What it does | When it fits Alaska |
|---|---|---|
| Manual heat/cool switch | You pick the mode by hand | Makes sense here, since few homes have equipment built for automatic changeover in the first place |
| AUTO changeover | Thermostat switches between heating and cooling on its own | Only relevant to the small share of homes with a heat-capable cooling system; costs more to run if the gap between setpoints is narrow |
| Wide deadband between setpoints | Leaves a gap so the system doesn’t fight itself | Prevents the house from heating in the morning and then cooling the same air it just paid to warm |
| Opening windows | Free, passive cooling | Usually the better answer, given how low actual cooling demand runs across the year |
The costly mistake is a narrow gap between heating and cooling setpoints, say three or four degrees. On a day when the morning is cool and the afternoon mild, that narrow gap can trigger a heating call at dawn and a cooling call by early afternoon, spending energy twice to fight the same swing a wider deadband would have absorbed for free.
And the changeover in the other direction
There’s no clean date to circle for when Alaska heads back into heating season, because it never fully left. Heating demand troughs at July’s 174 degree days and starts climbing again through August (236) and September (471), a steady rise rather than a single switch-flip moment.
What matters more than picking a date is matching the pre-season check to what the house actually heats with. With 37% of homes on furnaces and 36% on steam or hot-water boilers, roughly split, the fall checklist looks different depending on which one you have. Furnace households are back to the filter and airflow checks already covered above. Boiler households need their pre-season list to focus on bleeding air from radiators and checking system pressure, since there’s no filter in that loop to change.
Either way, the mechanics of the actual heating-season checklist, the deeper maintenance most homes need before demand climbs back toward January’s peak of 1,493 degree days, belongs in a dedicated guide rather than a summary here. This page’s job was narrower: to say honestly that Alaska doesn’t get a real off-switch, only a quieter stretch worth using well.