The short answer
A flashing snowflake on a thermostat in a Northern Virginia home almost always means one of two normal things: the thermostat is calling for cooling, or it’s holding the compressor off for up to 5 minutes so it doesn’t restart too fast. Some thermostats spell that delay out in words instead, like Wait or Waiting For Equipment. Give it 5 minutes. If the outdoor unit still won’t start after that, or the snowflake flashes all day with no cool air at the vents, something in the system needs a look.
What each icon is telling you
These meanings are from White-Rodgers’ manual for its 1F89-0211 thermostat (White-Rodgers and Sensi are the Emerson thermostats). Other brands use similar icons, so check your manual if yours isn’t one of them.
Swipe to see all columns →
Swipe to see all columns →
| What you see | What it means | What to do |
|---|---|---|
| Snowflake, steady | Cool mode is on | Nothing |
| Snowflake, flashing | Calling for cooling | Wait 5 minutes for the compressor |
| Flame, steady | Heat mode is on | Nothing |
| Flame, flashing | Calling for heat | No heat after a few minutes? See furnace won’t turn on |
| Setting flashing | Compressor lockout, up to 5 minutes | Wait it out |
| Sensi Set To flashing | Sensi’s A/C Protection, 5 minutes | Wait it out |
| EMER flashing | Emergency heat: backup heat only, heat pump off | Costs more to run: aux vs emergency heat |
| AUX | The backup heat stage is running | Normal on cold mornings with a heat pump |
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Why the compressor waits
A compressor that just shut off has high pressure on one side and low pressure on the other. Restart it before those even out and it starts against a load it wasn’t built for, which is hard on the motor and can trip the breaker. So the thermostat holds it off. White-Rodgers calls it a compressor lockout, there “to prevent the compressor from cycling too quickly”. Sensi calls it A/C Protection and sets it at 5 minutes. You’ll see it most right after the system shuts off, after you change the setting, and often after the power blinks.
Heat pumps wait too
A heat pump heats with the same compressor it cools with, so the delay covers heating too. Sensi’s delay applies to the A/C or the heat pump, and a White-Rodgers on a heat pump can flash its setting in Heat for the same reason. If the outdoor unit is crusted in ice instead, that’s a different problem: heat pump covered in ice.
When it doesn’t stop
Five minutes is the limit. If the snowflake is still flashing after that and the outdoor unit is silent, or it runs but the air at the vents isn’t cool, check these:
- The outdoor unit’s breaker in the panel, and the disconnect box on the wall near the unit.
- The filter. A clogged one starves the indoor coil of air: which filter and when.
- Ice on the copper lines or the coil. Turn cooling off and let it thaw before you try again.
- The fan switch. Set to On, the blower runs nonstop whether the compressor does or not.
If those check out, the usual parts are the run capacitor, $240 to $370 here, and the contactor, the relay that powers the outdoor unit, $290 to $425. One caution from White-Rodgers’ manual: don’t run the air conditioning when it’s under 50°F outside. On a cold night, leave it in Heat or Off.
Flashing flame and no heat
The flame flashes while the thermostat calls for heat. If it flashes and the house stays cold, the thermostat did its job and the furnace isn’t answering. Start with furnace won’t turn on, and if the furnace has a light blinking inside, what the blinking light means.
When it’s a call
Call when the snowflake or the setting keeps flashing past 5 minutes, when the outdoor unit hums but doesn’t start, or when the breaker trips again after you reset it. When we come out for a thermostat problem, the technician checks the whole system, not just the thermostat: the equipment, the wiring at both ends, the filter and the drain. The diagnostic is a flat $99, the repair is priced in writing before anything starts, and if the problem really is the thermostat, we say so. Our heating check is $67 per system, through December 31: furnace, heat pump or boiler.
Every brand’s codes and warning lights are in one place: error codes and warning lights. Words on the screen instead of icons? See what thermostat messages mean. Brand by brand: Sensi thermostat not working and White-Rodgers reset and screen meanings.
Model details are the makers’ own, from the White-Rodgers 1F89-0211 manual and Sensi’s A/C Protection page. Last checked November 10, 2026.
Book it
Book a visit online and put what the screen says in the note, or call (703) 997-9757, answered 24/7. Book from goswiftpro.com/cookiesoffer by November 30 and a box of warm cookies comes with the visit. Rated 5.0 stars across 1,138 reviews on Google, Angi, Yelp, the BBB and Facebook, Virginia Class A license 2705192276.
Questions people ask
Why is my thermostat snowflake flashing?
It’s calling for cooling, or it’s holding the compressor off for up to 5 minutes so it doesn’t restart too fast. Give it 5 minutes. If the outdoor unit still won’t start, check its breaker and disconnect.
Why does my thermostat say Wait?
On thermostats that spell it out, Wait means the same compressor delay. It clears on its own in about 5 minutes. If it doesn’t, the system needs a look.
How long is the thermostat compressor delay?
Up to 5 minutes on White-Rodgers thermostats, and 5 minutes on Sensi’s A/C Protection.
Why is my Emerson thermostat flashing a snowflake?
Emerson thermostats are White-Rodgers and Sensi models. A flashing snowflake means it’s calling for cooling, and a flashing setting, or Sensi’s flashing Set To, means the 5-minute compressor delay.
