Noise when furnace kicks on?
We have a gas furnace and im not sure how else to explain this... When it goes to kick on i hear this loud noise. Sort of sounds like a metal detector would over a certain type of metal. Or maybe robotic or alien like if you ask the children here lol. It lasts for maybe 4 to 5 seconds as its kicking on then stops. Everything else sounds normal. Its working. But i don't know anything about them. I've always had electric heat. Could it be the gas line? I dont smell a leak. Please help.
- InLv 73 weeks ago
If the filter element is extremely dirty it could have collapsed and is rubbing against the squirrel cage. If the filter is clean then maybe "elhigh" is on to something.
- elhighLv 73 weeks ago
That sounds like a spark ignition system.
Some furnaces ignite with a glowing hot heat element, others with a pilot flame (uncommon in modern applications) and some with a spark ignitor. The high voltage spark sometimes makes a noise you can hear.
- JohnLv 43 weeks ago
Fire Box heating up makes spooky noises.
- martinLv 73 weeks ago
Something in there is maybe loose, misfit, or rattling. Don't mess with it yourself. Get someone with experience.
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- Pat F85Lv 63 weeks ago
The rapid clicking noise you hear, when the furnace is starting up, is the spark arcing across the spark igniter .
The spark continues until the flame sensor 'senses' flame from the burners, then the spark igniter goes dormant until next time.
That is a normal amount of time of sparking sound for your furnace.
- MarkLv 73 weeks ago
No, the metal ducts (and furnace) are expanding with the heat.
- JayLv 63 weeks ago
good to know i guess