DIY Air-Heat Duct Cleaning - Free

Back in December we noticed that when we were at home we seemed more stuffed up.  The first thing i did was to replace the furnace humidifier filter.  According to my digital thermometer/humidity gauge it was only around 30% humidity in the house.  The new filter helped, along 2 humidifiers we put in our bedroom, but not completely.

I looked online and didn't really find anything about cleaning your own air ducts.  There was a ton of information about companies that will clean them for you.  As well as a Dateline episode which uncovered a common scam that furnace cleaning companies did.  Dateline set up some hidden cameras in a house and then called a company that said they would clean your heating ducts for some low price like $60.  The workers came out, said it would be only $60 then went into the basement.  They pretended to do something then came back up and told the woman pretending to be the homeowner that unfortunately her ducts were too bad and it was going to cost $430.  Even after she payed, the company never did clean the air ducts, they just put up some fake repair plates.

And that's the thing.  With heating ducts you can't really tell what condition they are in, most of the pipes are hidden from view.  Even if you take off the covers and look into the large cold air returns with a flashlight, you can only really see a few feet.  But luckily Karrie's dad used to clean duct-work years ago and he said i could do it myself with a leaf blower and a shop vac.  I would be basically doing the same thing as the pro's, just with different equipment.

The way in which professional companies clean heating ducts is that they cut a large hole in the ducts near the furnace.  That is where they hook up their large vacuum tube.  They then cover all the heat and cold air return vents and run compressed air "brushes" throughout your houses duct-work, which loosens all the dust, blows it toward the vacuum tube, and it is sucked out.  Here's a small portable professional version with the brushes.  They also have the larger vacuum running to their truck.

I would be doing the same thing, except instead of the industrial size vacuum i would be using a shop vac.  And instead of the compressed air brushes i would be using a leaf blower.  After covering all the vents but 1, i would turn on the leaf blower at that open vent and blow the dust toward the shop vac in the basement.  Then i would work my way down the line with the leaf blower.  I would have to do this with all the heat vents and cold air returns in the entire house.  Here was the equipment i would be using.

In case you don't want to continue reading i did make a video of the entire process.  The video will probably do a much better job of explaining  what i am doing.

DIY - Clean Your Air Heat Vents 

http://youtu.be/QdKvKpwGOkk

But the first step was to turn off the furnace.  That was as easy as flipping the switch on the side of it.  Next i had to figure out where i was going to connect the shop vac.  Normally this would mean cutting a hole in the duct-work.  But luckily i already had access holes cut out.  I'm not sure if this means that my air ducts have already been cleaned, i think it does.  So instead of cutting a big hole i was able to just remove a few sheet metal screws.  There were access holes for both the heat vent (hot air blowing into the house) and the cold air return vent (cold air returning to the furnace).

I set up the shop vac with the hose in the vent and used some old insulation as a barrier to block the dust from getting to the furnace.  It's a little hard to see from this picture because of everything on the shelf in the background.  But it's my shop vac with the hose running up to the heating duct.

 Here's a close up of the hose and the insulation blocking the back side toward the furnace.

Next i had to go around to each heat vent and cold air return vent in the house and remove the covers.  Some of them were really stuck on and painted over, but after an hour or so i got them all off.  That's when i learned that the dust in the cold air returns was probably twice three times as bad as the heat vents.  That kind of makes sense, the cold air returns were always located along the floor and as the air gets sucked back toward the furnace it brings with it all the dust from the floor.  But i was surprised at how bad some of the cold air return vents were.  This was the worst vent in the entire house, it was under the step from the living room to the kitchen.

So i decided that before i did any blowing air with the leaf blower, that i should vacuum out as much as i could reach with the shop vac from the vents themselves.  

During the whole air duct cleaning process i always thought that i was going to end up with this huge amount of dust clumps in the shop vac, but that was not the case.  When you vacuum the carpet you are picking up all the big heavy dirt and debris and that stuff does have a lot of volume.  But things that get into your duct-work are the light and airy stuff.  By the end of vacuuming out the vents the inside of the shop vac looked the same, but the filter was completely clogged with dust.  

After all the cold air returns and heat vents were cleaned i covered them with cardboard and paper bags.  That way when i turned on the leaf blower, all of the air and dust would be directed to one place, the shop vac in the basement.  I also had to remember to cover the vents in the basement.

I started with the heat vent furthest from the furnace.  After turning on the shop vac in the basement i went up and started blowing air down the vent with the leaf blower. 

During that time i went back down into the basement and listened and looked for which vents the air was blowing through.  It was fairly easy to tell which vents the air from the leaf blower was blowing through.  This is when the pro's use that air brush to snake through the vents and loosen up all of the dust.  I decided to go with the highly technical approach of just pounding on the vent with the palm of my hand.  Hopefully loosening up any of the dust stuck to the side wall of the vent. 

I did this for about 3-4 minutes.  Then went back upstairs, turned off the leaf blower, covered that vent, went to the next vent which was the next down the line closer to the furnace and repeated the entire process.  Half way through the process, while in the basement trying to find the right heat vent to pound on, i realize that there was more than one heat vent exiting the furnace.  There was actually 3 more heat vents on the back side.  So for those i turned the shop vac hose 180 degrees and started vacuuming from that direction.  It wasn't ideal but hopefully i could suck up the dust before it got down into the burners.

After doing all this for the heat vents i then had to do it all over again for the cold air returns. 

That meant changing the location of the shop vac.  I had to move the hose and insulation over to the cold air return duct.  Luckily though this was the only point in which the cold air returned to the furnace, which meant that i didn't have to turn the hose around at any point.

So another hour and i had all the heat vents and cold air returns blown out and sucked up.  Again after checking the shop vac it didn't look like i really got much dust, but the filter was pretty clogged with dust.

The final thing was to take off all the cardboard and replace the vent covers.  Then i screwed the sheet metal access hole plates back into place and switch the furnace back on. 

I'm not sure it ended up making a huge difference.  Although some of the cold air returns looked dirty near the opening, i'm not sure that the vents themselves were all that bad.  A couple of times while cleaning, i took out the shop vac hose and saw that it was only a light flow of dust coming out.  Not the huge clumps of gray dust that i envisioned.  But it's been about a month and i think we are sleeping a little better, not waking up from the dry air blowing from the furnace in the morning.

All in all it was a lot of work, it took me about 4 hours in total and a lot of running up and down stairs.  But i'm glad i got all the vents cleaned out and even happier that it didn't cost $450.