Air duct cleaning service providers may tell you that they need to apply a chemical biocide to the inside of your ducts to kill bacteria (germs) and fungi (mold), and prevent future biological growth. Some duct cleaning service providers may propose to introduce ozone to kill biological contaminants. Ozone is a highly reactive gas that is regulated in the outside air as a lung irritant. However, there remains considerable controversy over the necessity and wisdom of introducing chemical biocides or ozone into the duct work.
If no one in your household suffers from allergies or unexplained symptoms or illnesses and if, after a visual inspection of the inside of the ducts, you see no indication that your air ducts are contaminated with large deposits of dust or mold (no musty odor or visible mold growth), having your air ducts cleaned is probably unnecessary. It is normal for the return registers to get dusty as dust-laden air is pulled through the grate. This does not indicate that your air ducts are contaminated with heavy deposits of dust or debris; the registers can be easily vacuumed or removed and cleaned.
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if you do not want to put that dryer cleaner down your ducts (I don’t because if it gets stuck somewhere you will be stuck calling a pro to get it out! anyway what I did was take the furnace filter out for max air flow, and then close off all your vents leaving only one open at a time to clean. This directs all the air from your system only to the vent going to the opening you are cleaning. Then stick the flexible tubing of your vacuum cleaner down a bit into the vent and turn on the vacuum. Then go to the thermostat and turn on the fan only and let the vacuum run for a few minutes. That does a great job and you can do it with or without the brush. When done put a fresh filter in. I only do this for the vents where the air blows out. I would not recommend cleaning the cold air returns this was as you would likely be forcing dirt and dust into your furnace. If you want to vacuum the cold air returns, turn the system off
If I could rate this company a zero I would in a heartbeat. I purchased the service off of Groupon and to say that the groupon was misleading is an understatement. I was at work and my girlfriend was at the house when they got there (keep in mind it took six months for them to be able to get there because they were over booked). They tried to upcharge my girlfriend $250 immediately upon getting there. I told her to put me on the phone and spoke with the guy myself. He said that he would have the manager call me and that he would just start on the service. I received a text from my girlfriend 10 minutes later that the people had left. I never received a call from the manager. They didn't do all vents in the house. All they did was the main floor. It was a pathetic attempt to say the least.
Pay particular attention to cooling coils, which are designed to remove water from the air and can be a major source of moisture contamination of the system that can lead to mold growth. Make sure the condensate pan drains properly. The presence of substantial standing water and/or debris indicates a problem requiring immediate attention. Check any insulation near cooling coils for wet spots.
Most people are now aware that indoor air pollution is an issue of growing concern and increased visibility. Many companies are marketing products and services intended to improve the quality of your indoor air. You have probably seen an advertisement, received a coupon in the mail, or been approached directly by a company offering to clean your air ducts as a means of improving your home's indoor air quality. These services typically — but not always — range in cost from $450 to $1,000 per heating and cooling system, depending on:
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