Demonstrate visible evidence of microbial growth in your duct work. Some service providers may attempt to convince you that your air ducts are contaminated by demonstrating that the microorganisms found in your home grow on a settling plate (i.e., petri dish). This is inappropriate. Some microorganisms are always present in the air, and some growth on a settling plate is normal. As noted earlier, only an expert can positively identify a substance as biological growth and lab analysis may be required for final confirmation. Other testing methods are not reliable.
In most modern homes with up-to-date heating and air conditioning systems, filters are changed regularly through the year, so you may not even need to hire a professional. However, keep your eyes open for the accumulation of dust, dirt, dander and mold. If you see it despite regularly changing your filters it could be an indication you need a high-pressure cleaning.
"I had called around for other estimates all at the same time for vent cleaning. I chose to go with this company for a few reasons. One is because they promptly returned my call, but didn't blow up my phone with multiple calls looking desperate for business like a couple others did, making me feel that they were eager to pencil me in. They were very nice on the phone, answered all my questions, and even volunteered some information (I think because they could tell this was the first time I was getting a dryer vent cleaned and really didn't know what to expect). They explained everything they were going to do, what the charges were etc. They explained that there wasn't any hidden fees. When I started asking them about the other add'l fees that the other companies were charging (add on for if it vents out a 2nd floor roof, add on if they have to clean anything add'l, one even said they couldn't give me an estimate until they came out to my house), they said it was all included. It's one flat price including everything. They were prompt on the appointment, let me know when they were coming, and let me know if I had any questions after they leave, to just feel free to call. They were also honest about telling me that although some companies will tell you this should be done yearly, it's not necessarily true. Each family and usage is different. He could have been out for more money (like the other companies) and just said follow back up in a year or two, but instead he explained that mine wasn't truly that bad (and even showed me what was cleaned and pulled out of the vent) and told me that maybe 3 years would be the follow up time. The fact that he was honest, not pushy, not just after another appointment on the books for money, and took his time to explain what he was going to do, what he did, and was very pleasant while he was here, .....I would definitely use them again, but also recommend this company for sure !!"
I can’t believe I got ripped off by this Air Duct Cleaners. I called them for this $63 coupon per furnace unlimited vents then when they came after he checked it all I hear is I have molds and leak all is worth $499, $799, $899 per furnace but I told him to just clean the duct and patch the single leak per furnace worth $38 each. Still eanding $899 total. All the work he done is in less than an hour he didnt even go to each vent to clean it. All he did is to path the air leak on that entry pipe to the furnace and open the main venting system, vacuum it, and wash the floor of the vent with a solution. Overall time is about 20 mins talking with me discussing all the option which thinking they made me think I don’t really have an option and 40 mins wash and vacuum he took pictures of before and after of only one furnace. He gave me a receipt without the details on what he has done in the house just the name and price. I think we may need a strict law to punish and control all this companies who do this so other company who do good will despise them.
I can't believe the number of people saying a good properly installed central heating system never needs to be cleaned. Maybe they live in hermetically sealed cells? One look into a cold air return and you can see that it definitely needs periodic cleaning. The air in the house "always" has some dust in it and that's where it ends up. We just had ours cleaned and I saw what came out of it, disgusting. But always ask if they use the "air whip" to sweep/beat the inside of the metal duct. If not, don't bother. These folks used a little whip on the end of a pressure hose and swept the entire length of all the ducts. I have lighted bore scope that allowed me to see into the duct after he was done and it was spic and span. But do change your filters often, 2 or 3 times a year.
I read your article with interest and think it is a good start. One service that is always talked about is fogging ductwork for sanitizing. Many companies offer this service for disinfecting or adding a clean smell to the ductwork. Before any chemical or disinfectant is used, please read the MSDS (Material Safety Data Sheet). You might be surprise on what you are putting into the air stream. This is a high profit service and should be explored thoroughly before purchasing,
Some research suggests that cleaning heating and cooling system components (e.g., cooling coils, fans and heat exchangers) may improve the efficiency of your system, resulting in a longer operating life, as well as some energy and maintenance cost savings. However, little evidence exists that cleaning only the ducts will improve the efficiency of the system.