I have a Bryant Quietline Deluxe furance model 397EAW036100. I have been told it's between 20 to 30 years old. It makes a loud buzzing noise when it kicks on and then the blower will start. The noise continues until the flames stop, but the blower will continue for about a minute or so then stop. It happens 95% of winter. I had the whole thing cleaned and checked out 2 years ago and ask everyone who comes to my home and no one seems to know whats up. They say if it's not broke don't fix it. It's maddening. I had the ducts cleaned out too. They were fine for about a month. I can dust my house and an hour later, the dust is back. I have had it and I am sick of cleaning all the time. Even in the summer when the air is on I get the dust. I replace the filter and now use the 3M 3 month filters. I clean the area where the filter fits and still have dust. Oh, and I tape cheesecloth to the vents (which is ugly) to try to trap dust. Can anyone give me any help? I'd really appreciate it.

***Yes, there is a humifier working on the unit. It is 2 years old installed with new A/C unit, but the noise was present before the unit was installed. There was a humidifier before the new one was installed as well. I am using the 3m pleated 3 month filter. I have not worked on the furnace in anyway other than changing the filter and sucking dust from the bottom of the bed of the furnace. The last professional that was here was 2 years ago.

NorthernHeat

Are you using some type of humidifier? What type of filter? The buzzing sounds like the gas valve, but ther is a specific type of ignition control board that will do that too, but I think your furnace is to old to have it.

dustyducts

Thanks!

NorthernHeat

I asked about the humidifier because there are allot of cold mist humidifiers that atomize calcium and minerals in water that cause this dust complaint.

dustyducts

Thank you for the reply. The humidifier is an Aprilaire model 550. I forgot to turn the handle to winter when the furnace first went on in the fall. Realized it in December. The dust was the same either way. That buzzing noise is awful. Do you think if I had the gas valve replaced, it would solve the problem? Other than having a pro come in to check, would I be able to detect the ignition board?

NorthernHeat

I'm not sure you will be able to find the exact same gas valve if that furnace is that old, a new one may have to retrofitted and that takes a decent amount of knowledge. I also didn't find out what you are using for a filter.

dustyducts

Sounds like I might just have to put up with the buzz. The furnace filter I am using is 3M pleated allergy filter 3months usage. I have tried all different kinds with the same results.