Choosing Heat & Airin Washington
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Are fans enough, or does your Washington house need AC?

Fans or Air conditioning

Compared by the people who run this site. Updated . Rebates and prices checked November 3, 2026.

Whether fans are enough or you need AC is really a question of how hot the room gets, because a fan moves air and doesn't cool it. On milder days a fan can do. For a heat wave, plan on air conditioning for at least one room, or a cooler place to go.

The verdict, by situation

  1. If you have no AC and are deciding before next summer

    Plan on AC for at least one room. Ready.gov says: "Do not rely on a fan as your primary cooling device."

  2. If your indoor thermometer reads less than 90°F

    A fan fits CDC's wording. CDC: "Use fans, but only if indoor temperatures are less than 90°F."

  3. If your indoor thermometer reads above 90°F

    Not a fan, by CDC's wording. CDC adds: "In temperatures above 90°F, a fan can increase body temperature." Get to a cooler place.

  4. If the room has reached the mid-90s or higher

    Stop counting on the fan. EPA: "When it is that hot, electric fans will not prevent heat-related illness."

  5. If someone is confused, slurring words or has fainted

    Call 911. The National Weather Service lists these among the signs of heat stroke: "Call 911 or get the victim to a hospital immediately."

  6. If you live around Yakima or Pasco

    AC. NOAA normals show 40.2 days a year at 90F or more in Yakima and 54.7 in Pasco.

A low single-storey blue-green double house with a summer-browned lawn on 19th Ave SW in West Seattle.
A low single-storey blue-green double house with a summer-browned lawn on 19th Ave SW in West Seattle.

Side by side

CompareFanAir conditioning
Cools the airNo: EPA says portable fans "do not cool air"Yes
CDC lineOnly if indoor temperatures are less than 90°FNo fan limit applies
EPA lineNot for cooling when the room is in the mid-90s or higherNo fan limit applies
NWS line"may actually make them hotter if heat index temperatures are above the 90s"No fan limit applies
WA homes using itCeiling fans: 44%AC: 53%
SizingNoneBy room or by load calculation
In a power cutStopsStops

Sources: CDC: heat and health, EPA: extreme heat and indoor air, NWS: heat illness, EIA: RECS 2020. Each agency words its limit differently and measures a different thing, so we print each as written and don't average them. Washington DOH's hot-weather page gives no fan temperature. The table can't show how your rooms hold heat.

What would change the answer

  • Anyone at home gets dizzy, nauseated or develops a headache: DOH says to move somewhere cooler, rest and slowly drink a cool beverage, and to seek medical attention immediately if you don't feel better.
  • Your upstairs reads far hotter than your ground floor: DOH points people without AC to the lowest floor, out of the sun.
  • You can't fit or power any AC: then the plan becomes a cooling center, found by dialing 2-1-1.
  • Smoke arrives with the heat: open-window fan cooling stops being simple, as windows open or closed explains.
  • Your west side house has sun-struck windows you can shade: DOH says awnings or louvers can cut heat entering by as much as 80 percent.

What it costs, with dates

We won't put a running-cost number on a fan or a room unit without your label. We found no official installed-price figure for AC, and no agency running-cost figure for fans. Read the watts on the label, divide by 1,000, then multiply by your hours and your rate.

Washington's residential average was 14.63 cents per kWh in August 2026, up from 13.65 a year earlier. Your utility's rate will differ. As of November 2026 we found no rebate for a fan or a cooling-only room unit.

For anything a contractor installs, get written bids itemizing equipment, electrical work and permits. If that work includes heat, rebate or wait covers what's available.

Who does the work

Fans are yours alone. So is the thermometer: put one in the room where you spend the hottest hours, because the agency lines depend on how hot it actually is.

A portable needs no installer. A window unit must be secured exactly as its manual says; if the sash or sill is doubtful, have someone qualified fit it or choose a portable. Anything with an outdoor unit or new wiring goes to a contractor. Check them on L&I's tool and read who pulls the permit first. If a room unit stops, checking the breaker is as far as it goes for you.

What did the 2021 heat dome show about going without AC?

It showed that Washington, even the west side, can reach deadly heat. Sea-Tac hit 108F on June 28, 2021, after 102 and 104 on the two days before. Pasco reached 115 on June 27.

Washington DOH later reported 157 heat-related deaths between June 26 and August 31, 2021. The same report counted 1,232 excess deaths during the heat dome, which is 826 more than the COVID-19 (249) and heat-related (157) deaths reported around that time. Excess deaths are a different measure from a heat-death count, so the two figures shouldn't be read as one number.

Those are the reasons we don't treat a fan as the plan, even in a place with only 3.8 days a year at 90F or above, as at Sea-Tac.

Still from the video Warning Signs During Extreme Heat | UW Medicine
Video, 1:36. UW Medicine runs through the warning signs of serious illness during extreme heat.
A worn white digital thermostat reading 80 in cool mode on a beige wall. Reading the temperature, rather than guessing, is how you apply CDC's and EPA's lines.
A worn white digital thermostat reading 80 in cool mode on a beige wall. Reading the temperature, rather than guessing, is how you apply CDC's and EPA's lines.

What are the signs that heat has become an emergency?

Confusion, slurred speech or fainting mean call 911. The National Weather Service list for heat stroke is:

  • throbbing headache, confusion, slurred speech, nausea or dizziness
  • body temperature above 103F
  • hot, red, dry or damp skin, with a rapid, strong pulse
  • fainting or loss of consciousness

NWS also says not to give fluids to someone with heat stroke. For heat exhaustion, it says to seek help if the person is vomiting, or symptoms worsen or last longer than 1 hour.

What should you buy first if you have no cooling at all?

Start with one room that you can keep cool, not a new fan. A room unit sized by ENERGY STAR's method is the smallest step, and portable or window AC covers the choice. If you are considering more, read one cool room or the whole house.

Fans still earn a place. EIA finds ceiling fans in 44% of Washington homes, and on a milder evening one can be all you need. The overviews for the west side and the east side put this in context.

What people ask next

Should I run a fan in the window at night during a Washington heat wave?

EPA's window rule is simple: if air outside is cooler than inside, open; if hotter, close. Check for smoke first, since the coolest time of day can be the smokiest.

Does the DOH give its own temperature limit for fans?

Not on its hot-weather page. That page gives no fan temperature, so use the CDC or EPA line as each one wrote it.

Where do I go if I can't cool my house at all?

Dial 2-1-1 for cooling centers in Washington. Go before anyone shows symptoms.

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Where this came from

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