The usual suspects
Defrost cycle steam — normal
Melting frost flashes to vapor on the warm coil for 2–10 minutes, every hour or two on cold damp days. Puget Sound winters make lots of it.
Fog vs smoke
Steam is white, dissipates, and smells like nothing. Smoke is darker, persistent, and smells burnt — different story entirely.
Excessive defrosting
Steaming every 20 minutes means the system is icing too fast — low charge or a sensor fault.
Electrical burning
Acrid smell with any haze = shut it off at the breaker.
Rather be sure?
A quick defrost-cycle check confirms boards, sensors and charge — cheap certainty, priced upfront.
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Worth trying first (5 minutes, free)
- 1
Watch and time it: a few minutes of steam, then normal running = textbook defrost.
- 2
Sniff test from a distance: no smell = water vapor; burnt = breaker off, book now.
- 3
Count the frequency across a day — hourly is fine, constant is not.
Still not working? Then it’s a technician job — and the sooner it’s booked, the sooner the house is comfortable again. Book the visit →
Stop and book a pro if…
- Anything that smells burnt or electrical — breaker off first.
- Steam events every 20–30 minutes all day.
- Steam plus ice that never actually clears.
- Popping or sizzling sounds with the haze.
Why homeowners hand it to us
- You approve the price first. Upfront quote before a single screw turns.
- Same-day service. Book in a minute, hear from a tech within 1 business hour.
- 500+ jobs done by 4.9★ rated, professional technicians.
- Fixed right, guaranteed. If it’s not right, we make it right.
Quick answers
The neighbors said my unit was smoking. Should I panic?
Almost certainly defrost steam — dramatic-looking and harmless. The tell is that it fades in minutes and smells like nothing. Burnt smell or persistent haze is the version that earns a shutdown and booking.
Why does it steam more on some days?
Cold plus humid is maximum frost weather — classic Washington winter mornings. More frost, more defrost, more steam. Dry cold days barely steam at all.
Can defrost be checked proactively?
Yes — it’s part of a heating tune-up: board, sensors, coil condition and charge. Cheap insurance before the cold snap hits.
Done guessing?
If the pattern doesn’t match "normal," book it — defrost faults compound in cold snaps.
Book My Same-Day Visit60 seconds online · or call (206) 486-6373
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