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Huntn

macrumors Core
Original poster
May 5, 2008
23,476
26,596
The Misty Mountains
That should be ducts, haha. :)

Seriously, my wife has been bugging me to get our AC ducts cleaned for sometime so I finally got around to it picking a cleaning company in the Houston area that charged about $250 to do this. Another company charged $450 so I went with the less expensive company- don't say anything. ;) There was however a hitch- a couple of the ducts had mold on them and there was some mold in the same ducts. I asked how much to treat mold and the answer $499 to spray some stuff in the return duct and allow it to blow out through the AC system. I asked why it was so expensive and was told the chemicals were top notch, non-toxic to humans and because a 2 year warranty was offered. The name of the stuff was Mold Maximum Oder Treatment that looked and smelled like a detergent and did not say anything about it being a herbicide (mold remover), but it smelled good. Without proof, deep down I suspect this is a duct cleaning scam, but bottom line I don't know for sure. Anyone have any experience with this?

I had not researched this in advance, not even thinking about mold, and was unsure of the effectiveness of this treatment but paid it. I have no clue if this company is performing an honest mold treatment service or they took some detergent and sprayed it in the ducts for $499 and a 2 year warranty. I have done some research and the word is that most houses have some mold in them in the AC duct. What is important is that you not allow it to get out of hand and to avoid the black toxic stuff, although there can be black mold that is not toxic. See this article.

My experience cost me a total of $800. Most of my concern is regarding 10 minutes of spraying "something" into my return duct as a means of killing mold. From what I've read, duct cleaning which includes mold can range from $600-$2000.For anyone considering their ducts cleaned, and you live in a hot/humid climate, I suggest you give the company a grilling in advance regarding mold treatment, what chemical they use, what they charge, and check the BBB or Angie's list. I spoke with my brother who works in the building trades afterwards and he tells me companies frequently use scare tactics to get you to buy the mold treatment. Regardless, the bottom line is that mold should not be ignored.
 

neiltc13

macrumors 68040
May 27, 2006
3,126
19
I don't think I have ever been in a house that had air conditioning. Pretty surprising how much it costs just to keep it running.
 

Shrink

macrumors G3
Feb 26, 2011
8,929
1,727
New England, USA
I don't think I have ever been in a house that had air conditioning. Pretty surprising how much it costs just to keep it running.

In my small condo (~1250 sq ft) my central air costs an additional $15-20/month for about 3-4 months a year.

Not a give away...but not back breaking financially, and it means comfortable days and a decent night sleep (as good as I ever get, anyway!):D

I probably should have my ducts cleaned (and some other things, but this is a family forum)...too expensive for now.
 

dmr727

macrumors G4
Dec 29, 2007
10,420
5,159
NYC
I don't think I have ever been in a house that had air conditioning. Pretty surprising how much it costs just to keep it running.

Not sure what the climate is like where you are, but IMO the cost of air conditioning is a small price to pay, especially when living in hot and humid areas. I live in a relatively non-humid region about a mile and a half from the ocean, and even then there are a couple of weeks out of every year where central air is a blessing. My situation is similar to Shrink's - I'd guess the A/C adds about twenty bucks a month to the electric bill.
 

brad.c

macrumors 68020
Aug 23, 2004
2,053
1
50.813669°, -2.474796°
What's done is done, so there's no point second guessing yourself at this point. :) But honestly, I don't think I would have proceeded without a second opinion on the assessment and treatment. Plus, if the treatment failed, all they are promising to do is come back and give it another go? Sounds like a second shot at failure.

But we're also talking health and peace of mind. If there is no visible trace left, consider it a precautionary step.
 

Huntn

macrumors Core
Original poster
May 5, 2008
23,476
26,596
The Misty Mountains
My apologizes to those who really wanted to know how to clean your ducks. :)

Not sure what the climate is like where you are, but IMO the cost of air conditioning is a small price to pay, especially when living in hot and humid areas. I live in a relatively non-humid region about a mile and a half from the ocean, and even then there are a couple of weeks out of every year where central air is a blessing. My situation is similar to Shrink's - I'd guess the A/C adds about twenty bucks a month to the electric bill.

In contrast if you live just about anywhere down south, your AC kicks in about April and it runs till October. ;) My estimate it adds about $250 per month to my electric bill in the hottest months, that's 90-100°F every day. We plan on upgrading to a newer more efficient unit in the near future.

About the mold, living in Minnesota it was never an issue in the AC ducts. I think I forgot to mention it but if you live in a hot/humid climate, don't close off the AC ducts in the unused rooms, like a guest bed room. In my case this is where the most mold appeared on the inside of the registers in those two rooms.

Even on Dvorak, k and t are on different hands for typists. :confused:

It's a trap to snare the unsuspecting. ;)
 
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G51989

macrumors 68030
Feb 25, 2012
2,530
10
NYC NY/Pittsburgh PA
I don't think I have ever been in a house that had air conditioning. Pretty surprising how much it costs just to keep it running.

Trust me, where I live. It turns on in about April, and except a couple days it never shuts off. During the summer, the 200 bucks a month is totally worth it.
 

MacNut

macrumors Core
Jan 4, 2002
22,995
9,973
CT
Is there a leak in the duct, I thought that sealed systems don't usually need to be cleaned of mold.
 

blazerdude20

macrumors member
Jul 19, 2008
67
6
I work in the Hvac field and have done a few duct cleanings. I have a question for you:

What kind of duct work do you have? sheet metal, fiberglass duct board (insulation inside duct), or flex duct?

With bare sheet metal the growth of mold is fairly rare but very easy to clean with light chemical. Fiberglass duct is near impossible to clean and you CANNOT prevent regrowth of mold due to the fiberglass retaining moisture and spores.

If you have a newer home you likely have flex ducts running from the main to your registers. Flex duct can be cleaned by a cleaning service (prone to damage though). Many sketch companies will charge you for cleaning the flex even though they can't clean anything other than the main sheet metal duct from the furnace.

If there was mold in your ducts (its possible) you need to find the cause of the mold. Many times it can be caused by moisture from your ac coils not draining outside.

Here is some reading from the EPA. http://www.epa.gov/iaq/pubs/airduct.html#Are
 
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GoCubsGo

macrumors Nehalem
Feb 19, 2005
35,741
153
Within months of buying my house there was a smell that was almost deathly. Long, long, story short, there were a few issues. Critters made their way in the crawlspace and made a home. The ducts at some point were replaced but not all ducts were replaced. They used below code ducts and hooked them into existing ducts. The ducts were secured to a gas line and water pipes using consumer-grade zip ties (not code). They were routed like a maze and just wouldn't provide the airflow one would want. The fact that a large circle (duct) was being put into a small circle (duct) there were gaps. Gaps were filled by squeezing the ends together with more zip ties daisy chained together.

In short, I had major issues. Flex duct is not something they wanted to clean. Whether they can is another story because I am not sure. I ended up having them replace all ducts because we didn't know where the stench was coming from and I have asthma. Because of the asthma, allowing anyone to spray anything with the intention of having it "clean out through the AC" sounds absolutely wrong.

The best subscription I have ever paid for is to Angie's List. I cannot recommend it more to anyone. At the very least, it helps me make slightly more informed decisions.
 

SeanR1

macrumors 6502
Jan 4, 2009
300
8
Pennsylvania
SWa6l.gif
It's a trap to snare the unsuspecting. ;)
 

blazerdude20

macrumors member
Jul 19, 2008
67
6
W The ducts were secured to a gas line and water pipes using consumer-grade zip ties (not code).

That is very scary. Over time a copper gas line touching a metal duct will corrode and eventually cause a gas leak that could blow up your home.

Glad you were able to get a qualified person to replace your system. :)
 

Carlanga

macrumors 604
Nov 5, 2009
7,132
1,409
Isn't a herbicide for weeds though? Fungicide, I believe is what you want for mold. :p

Your story reminds me of an old episode of Hank Hill (After the Mold Rush-Season 8, Episode 6) :cool:

Anyways, you should go to their store or facility and ask nicely what is it exactly that they are putting inside the vents and for them to show it to you. Make sure you read on the common ones and the ones that are not as safe.
 
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