What's Your Opinion on Duct Cleaning?

[paulsharvey]

If you use a filter, you shouldn't have any, or much crap in your duct work.
If your duct work is insulated on the inside, it's a bad idea to have them cleaned. I would just replace the duct work and have the ducts insulated on the outside . You are breathing more insulation fibers than you are the dust

It's not just the duct board, with accordian style, I would be worried about them damaging it.

If there is a problem, sure, fix it, and clean; but I think it's 90% scam, and 10% a temp fix to a symptom of a problem it doesn't fix.

 

[MossRoad]

If you use a filter, you shouldn't have any, or much crap in your duct work.
If your duct work is insulated on the inside, it's a bad idea to have them cleaned. I would just replace the duct work and have the ducts insulated on the outside . You are breathing more insulation fibers than you are the dust

If you use a filter or not, you'll have all kinds of crap in your return ducts. Especially in an older home. That's where everything gets sucked into. Human hair, pet hair/fur, human and pet dander, general dust. Dust bunnies. It's nasty.

 

[MapleLeafFarmer]

IMO I would say it all depends.

I live in a 25 y.o. house that is 100% hardwood floors and tile. Due to wife disability. NO CARPETS. I have recently painted and run wires through my cold air ducts and re-routed some hot air ducts (forced natural gas furnace) and re-routed the central vent/heat exchanges.

All were almost spotlessly clean except at the entrance of the cold air ducts which seemed to collect some of the 25 years of dog hair that moves through the house. So all I needed to do was remove the covers and vacuum with the vacuum hose.

So I would say with hard surfaced floors, even with big dogs, it would be wasted money here.

Now if you have lots of kids, wear outdoor boots/shoes in the house, carpeted floors, etc.... YMMV.

Pull a few vent covers and take a look. You will quickly see if they need attention.


ps: I only change my furnace filter 1X every year or so. It stays clean. If your gets dirty fast or stays clean would also be good indication of vents need cleaning. Carpets wear over time and make huge amounts of dust as well.

 

[kenmac]

If you use a filter or not, you'll have all kinds of crap in your return ducts. Especially in an older home. That's where everything gets sucked into. Human hair, pet hair/fur, human and pet dander, general dust. Dust bunnies. It's nasty.

If you got all that crap in your duct work you really should consider sealing all the air leaks and using a quality filter.
Been doing this a long time and I've seen just about everything.

Now if the previous owners of the older home had not used a good filter, has air leaks in their system, I would suggest (A) a good cleaning, seal all joints / cracks with tape and mastic, and use a quality filter
Or (B) Have the duct work replaced , seal all joints/ cracks with tape and mastic, insulate on the outside, and use a quality filter

 

[kenmac]

It's not just the duct board, with accordian style, I would be worried about them damaging it.

If there is a problem, sure, fix it, and clean; but I think it's 90% scam, and 10% a temp fix to a symptom of a problem it doesn't fix.

I'm going to guess you're talking about flex ? So, your ductwork is duct board and flex ?
Replace it with metal and insulate on the outside. I'm not into breathing insulation fibers.
I started insulating metal duct work on the outside some 15-20 yrs ago

 

[HawkinsHollow]

Well he came today to take a look and I think I am doing it. $1600 out the door with the cleaning, which uses mostly strong air and air whips in a highly negative pressure environment. Meaning, they suck it all out with a huge vacuum while they dust it. Then they will spray a liquid rubber biocide duct coating in our square interior insulated trunk line. Then they are going to fog the entire system with a biocide because the branch lines don't get rubber coated, this will kill any mold that didn't get vacuumed out.

I am going to call a duct guy to see how much it would cost for new duct work, but money is running out really quick on this project and I think it will be too much. Especially considering we have round solid metal ducts. Seems like a waste to rip all that out for the new accordion crap.

I this this process is much bigger than your average duct cleaning and I have drank the koolaid. I believe that a 60 year old house has some gunk in the ducting for sure and removing it from the equation can't be a bad thing. My entire house is starting on a clean slate, why not the duct work as well? I will report back when its done about the process.

 

[ponytug]

Well he came today to take a look and I think I am doing it. $1600 out the door with the cleaning, which uses mostly strong air and air whips in a highly negative pressure environment. Meaning, they suck it all out with a huge vacuum while they dust it. Then they will spray a liquid rubber biocide duct coating in our square interior insulated trunk line. Then they are going to fog the entire system with a biocide because the branch lines don't get rubber coated, this will kill any mold that didn't get vacuumed out.

I am going to call a duct guy to see how much it would cost for new duct work, but money is running out really quick on this project and I think it will be too much. Especially considering we have round solid metal ducts. Seems like a waste to rip all that out for the new accordion crap.

I this this process is much bigger than your average duct cleaning and I have drank the koolaid. I believe that a 60 year old house has some gunk in the ducting for sure and removing it from the equation can't be a bad thing. My entire house is starting on a clean slate, why not the duct work as well? I will report back when it's done about the process.

@HawkinsHollow I would still have a look with an endoscope/borescope first. We have 50+ year old ducts, and they are spotless and basically dust free on the inside. The prior owners had dogs and cats, and a bird. There's a tiny amount of dust around the inside of the furnace blower housing, but I put that down to running the HVAC for awhile with a defective electronic filter. I am not trying to talk you out of cleaning the ducts; wouldn't you like to know how bad the "before" is?

I know that the duct cleaning folks really like to spray that rubber sealant inside the ducts, but since I know folks with allergies to rubber, personally speaking, coating an air duct with rubber gives me the heebie-jeebies. What sticks to it? What happens as it ages? What happens if it outgases chemicals, and most polymers will do that as they age? If someone picked up a sensitivity to one of those chemicals or the rubber, what do you have to do? Rip out all of the ducting?

I would note that I have never seen a spray rubber or other polymer on commercial ducting, even in areas requiring clean air. I just worry that the coating is truly snake oil.

All the best,

Peter

 

[CalG]

Just a note:
I was recently up doing a bit of work on my daughter's 19th century Vermont farmhouse. (She should have never bought the place, it's rotted to the sills, but that is a different issue)
any way, while rebuild sills and a wall in the kitchen I pulled a couple of supply vents and a return.
The shop vacuum tank just about filled up!
She keeps dogs and is not a tidy person. I advised her to keep up on the filter for her furnace.

 

[mikester]

I have no ducts nor ducks in my house.

When I get those spam calls I ask if they clean geese as well as ducks.

 

[2manyrocks]

I wouldn’t want rubber coating inside my air ducts. My concern would be creating an odor and the coating would tend to slow the velocity of air flow. Is it fireproof?

Did the guy scope your ducts and show you pictures?

Would not expect mold to grow on metal air ducts.

 

[HawkinsHollow]

When I get those spam calls I ask if they clean geese as well as ducks.

Hahaha, love it!!

I have done a bit more reading on the matter, the more I read the more I feel like I am making the right decision.
They say it is a good idea if:
-You have floor grates
-you have pets that shed
-your house is older (60 years old and more than likely never cleaned)
-you have any respiratory compromised or people with allergies in the house
- You just did a remodel
-your filters are dirty every month or so when you change them

Do I want to spend $1600 on this? NO! Is now the time to do it if I am going to do it? YES!

Thanks for all your feedback.

 

[HawkinsHollow]

I wouldn’t want rubber coating inside my air ducts. My concern would be creating an odor and the coating would tend to slow the velocity of air flow. Is it fireproof?

Did the guy scope your ducts and show you pictures?

Would not expect mold to grow on metal air ducts

The rubberized coating is just on the interior insulated main trunk line. Not in the ducts.
As far as odors, I am hoping they have figured that out already. There are times when you have to put your faith in industry professionals, most times that works out for the best.

Yes he scoped the ducts and I was sitting right next to him as he did. It looks like it needs it. You could see dust particles flying around as the camera moved around.

I don't think there is tons of mold growing in the metal branch lines. But if it is the system it is on/in the metal branch lines. This biocide fogging will eliminate anything in the system for a clean slate.

 

[HawkinsHollow]

On top of getting hte ducts cleaned I am going to put a dehumidifier down in this crawl space with a fan to move that dry air around. I am going to put an air filter on the fan to help remove particulate in the crawl space. That's gotta help.

 

[MossRoad]

If you got all that crap in your duct work you really should consider sealing all the air leaks and using a quality filter.
Been doing this a long time and I've seen just about everything.

Now if the previous owners of the older home had not used a good filter, has air leaks in their system, I would suggest (A) a good cleaning, seal all joints / cracks with tape and mastic, and use a quality filter
Or (B) Have the duct work replaced , seal all joints/ cracks with tape and mastic, insulate on the outside, and use a quality filter

The previous owner did things on the cheap. He had black labs. Lot's of them, as he was an avid hunter. And 4 daughters. And a wife. The house is 100 years old. The furnace is older than the 30 years we've been there. So yes, there are lots of air leaks in the system. I patched as many as I could find.

When we bought the house, it had a screen in front of an electrostatic air cleaner. If you'd stomp on the floor anywhere in the house, in about 5-10 seconds, you'd hear the thing start snapping wildly. The screens would get blocked about once a month and I'd clean them off and run the two sections of the air cleaner through the dishwasher as recommended. Yet we'd still see dust in the house, which I determined was mostly cat dander as mentioned before.

I finally had enough with the electrostatic cleaner, and found exact replacement filters. I disconnected the unit, removed the two sections, and replaced it with the filter. I left the screen in as a pre filter. I still clean the screen a few times a year, but it's now nowhere near as bad as when we had the electrostatic cleaner. I change the filter once a year, and I can still see through it. And we still have two cats.

It's a 16x25x5 MERV 12. Seems to do a much better job.

 

[Roric]

Might suggest this for homes with carpet and/or pets:

DIY Air Filter: How to Build Your Own Air Purifier

In this video and guide, we'll walk through the mechanics of DIY air filters and then help you build one for your home yourself.

www.thisoldhouse.com

Built several of these. Twice with grand kids and they had a ball.


regards

R

 

[MossRoad]

Might suggest this for homes with carpet and/or pets:

DIY Air Filter: How to Build Your Own Air Purifier

In this video and guide, we'll walk through the mechanics of DIY air filters and then help you build one for your home yourself.

www.thisoldhouse.com

Built several of these. Twice with grand kids and they had a ball.


regards

R

My son in law built one. It works pretty well. In fact, he built a 2nd one. They have two cats and two dogs. Amazing amount of fur and dander those things collect.

 

[kenmbz]

We just had our ducts cleaned. Less than $800 all in.
Took them many hours with a 2 man crew.

Previous owner had used electronic filter in AC housing with a pretty open filter in return.
I removed the now non working electrostatic filter and use a real filter in the return.

The duct cleaning was using a huge dual fan filter box, lots of vacuums and whips.

While not incredibly dirty, there was some stuff throughout the ductwork.

Had them do the mold treatment spray too for about $100 extra, made the wife happy.

 

[2manyrocks]

As expensive as metal trunk lines, ducts, etc are, there is no way I would let anyone do a single thing to any of it without me first knowing that there is a problem and that the proposed work will solve it without messing them up. Mere talk from sales people isnt enough.

 

[2manyrocks]

Further thoughts...I still wouldn't expect mold in metal ducts unless a house has been underwater. How is mold supposed to grow on metal that is subjected to a concentrated flows of dehumidified air?

I'd expect more air quality issues to arise from dirt trapped in the carpet or actual growing on floor joists in a damp crawl space or some bathroom leak over time.

 

[kenmac]

The previous owner did things on the cheap. He had black labs. Lot's of them, as he was an avid hunter. And 4 daughters. And a wife. The house is 100 years old. The furnace is older than the 30 years we've been there. So yes, there are lots of air leaks in the system. I patched as many as I could find.

When we bought the house, it had a screen in front of an electrostatic air cleaner. If you'd stomp on the floor anywhere in the house, in about 5-10 seconds, you'd hear the thing start snapping wildly. The screens would get blocked about once a month and I'd clean them off and run the two sections of the air cleaner through the dishwasher as recommended. Yet we'd still see dust in the house, which I determined was mostly cat dander as mentioned before.

I finally had enough with the electrostatic cleaner, and found exact replacement filters. I disconnected the unit, removed the two sections, and replaced it with the filter. I left the screen in as a pre filter. I still clean the screen a few times a year, but it's now nowhere near as bad as when we had the electrostatic cleaner. I change the filter once a year, and I can still see through it. And we still have two cats.

It's a 16x25x5 MERV 12. Seems to do a much better job.

A lot of times you'll know how bad your duct work is just by looking at the squirrel cage on the on the blower motor. If Those fins are caked with dust / dirt, your duct work is most likely caked with dust /dirt as well.. It's best to have all the cracks and seams sealed up on the return side before the furnace / AH.
The best thing you can have done to the supply side is to have new duct work installed and have the insulation on the outside of the supply duct.
Dust particles in the home is possibly coming from the insulation fibers braking down inside your supply duct, and being blown inside the home.

I used round duct here and it's insulated on the outside with metal supply duct also insulated on the outside. and of course, all seams are sealed with mastic, and or tape .