Whistling Furnace

[rrwd]

It's turned cold here in California and after turning on the furnace for the first time this year, I get a whistling tone as soon as the regulator turns on the gas and it lights. And, this is before the fan turns on and it starts blowing. Everything else seems fine and normal. This is a very old forced air furnace that's been in operations for over 20 years and only used a few months out of the year.

Is this something I could fix my self? Is it dangerous?

Thanks for helping!

 

[WorthFlorida]

Turn off the gas, take off the cover to the burners and with a vacuum cleaner or compressed air, clean out the air mixture adjusters. Could Be spider webs, a lot of dust or corrosion restricting air or gas flow. This is a pic I found on line. It's labeled air shutter.