The usual suspects
Boom or bang at startup
Delayed ignition — gas builds up before lighting and ignites with a thump. Hard on the heat exchanger; get it looked at.
Screeching or grinding
Blower motor bearings or a slipping wheel. Caught early it’s a motor job, run to failure it’s a bigger one.
Rumbling after the burners stop
Dirty burners letting flame linger — combustion that isn’t clean. A tune-up-level fix, but don’t sit on it.
Rapid clicking
The igniter sparking without lighting — ignition or flame-sense trouble, often paired with cold air.
Name that noise.
A 10-second phone video with your booking usually lets the tech arrive with the right part on the truck.
Book My Same-Day Visit60 seconds online · or call (206) 486-6373
Worth trying first (5 minutes, free)
- 1
Note when it happens: startup, steady running, or shutdown — that timing is half the diagnosis.
- 2
Check the filter and vents — whistling and some rattles are just starved airflow.
- 3
Record it on your phone and send it with the booking.
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…
- Booming at startup — delayed ignition stresses the heat exchanger; book promptly.
- Metal-on-metal grinding — shut the furnace off.
- Any gas smell with any noise — leave first, PSE’s gas line second.
- Your CO alarm and a new noise together — out of the house, then 911.
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 bang scared us. Is it dangerous?
A startup boom is a small internal explosion — the furnace tolerates a few, but repeated delayed ignition can crack the heat exchanger, and that’s the expensive, safety-relevant failure. It’s a book-this-week problem, minimum.
Can I run it until the visit?
Rattles and hums, yes. Booming, grinding, or anything with a burning or gas smell — no. When in doubt, heat off, and we prioritize the visit.
What will it cost?
You’ll know before we start — every repair is priced upfront and you approve it first. Booking takes about a minute.
Done guessing?
Noises only graduate into bigger repairs. Book while it’s still the small one.
Book My Same-Day Visit60 seconds online · or call (206) 486-6373
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