The usual suspects
Musty — mold on the coil or drain
A startup puff that fades points at the coil pan; constant mustiness points at ducts or a lazy drain.
Burning dust — briefly normal
First runs after a long idle bake off dust. Persistent burning — or hot plastic — is not normal.
Chemical or sweet — refrigerant
A faint chloroform-like sweetness, often with fading cooling. That’s a leak.
Rotten eggs — gas
Cooling uses no gas, but the ducts are shared with the furnace. Leave the house, call PSE’s gas emergency line.
Don’t live with the smell.
Coil cleaning and drain treatment kill the musty ones for good — quick visits, priced upfront.
Book My Same-Day Visit60 seconds online · or call (206) 486-6373
Worth trying first (5 minutes, free)
- 1
Note the pattern: startup-only vs constant — that fact does half the diagnosis.
- 2
Fresh filter + 30 minutes of FAN dries the coil and clears lingering startup smells.
- 3
Peek at the drain pan — standing water is a mold farm and means a lazy drain.
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…
- Rotten eggs: leave first, call the gas company from outside.
- Electrical burning: breaker off, book now.
- Chemical smell with weak cooling.
- Musty smell plus allergy flare-ups in the house.
What this usually costs
$150–$650 covers most AC repairs. A capacitor or contactor sits at the low end; a refrigerant leak repair or compressor work at the high end.
Typical industry ranges for Western Washington, not a quote — your exact price comes upfront, before any work starts, and you approve it first.
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
Why does it smell musty at every startup?
The blower is clearing air that sat over a damp coil — mold’s calling card. A coil clean and drain treatment usually ends it.
I smelled burning plastic and shut it off. Overreaction?
The right call. Hot-plastic or electrical smells are insulation or a motor cooking — a same-day diagnostic, not a wait-and-see.
Do you clean ducts too?
We handle coil, pan and drain — and if the ducts are truly the source, we’ll tell you straight and quote it upfront.
Done guessing?
A smell is the one symptom that finds YOU. Book the visit and breathe easy tonight.
Book My Same-Day Visit60 seconds online · or call (206) 486-6373
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