I've been in business in Florida for 25 years and purchased a $12,000 duct cleaning system 4 years ago. In the last four years I've cleaned 5 duct systems charging around $400 each. Not a very good return on investment. What I have been doing most the time is I get a call by someone panicked because they called some low priced company to inspect their system and were told they have dangerous black mold. Then they call me to have a look. Most the time they don't have mold, ducts look very clean. However the coils are dirty and the inside of the air handler cabinet needs cleaning. Keep in mind not every system can handle supper high efficiency filters! These filters can block air flow quite a bit right out of the package. Many older systems can't handle pleated filters due to increased static pressure. "Back rooms with low air flow". I have taken many hours of classroom study on indoor air quality. Never got any certification because I don't want to pay another organization dues yearly. I think the problem with duct / system cleaning is most people are suckers for low priced scams that are rip- offs . People call me all the time and ask how much? When I tell them average $400 they hang up. I know I do the job correctly and honestly, and they are going to get racked over the coals by the scam artists by calling $79 whole house duct cleaning guys. People need to check internet, angies list and BBB reviews. But keep in mind even reviews need to be sifted through your rational person filter.
I believe a $3 [sic] pleated cotton filter is all that is ever needed to keep a system running top notch. A cleaning of the blower squirrel cage and of the evaporator [indoor] coil may be needed one time if fiberglass or no filters have been previously used. The return air grille [or grilles] need vacuumed off occasionally, as they are upstream from the filter. The $3 filter should be changed every 3 months [rule of thumb]....and most of them have a little white square on the cardboard frame to write install date.....and the arrow should point into the duct [if at filter grille]....or towards the furnace [if in ductwork slot]...or towards the blower [if in blower compartment]. My two cents.....
I agree that good filtration and a sealed system will prevent the need for duct cleaning. However, when we do get called it is because the duct work has reached a noticeable state of restriction or dust or the homeowner is hyper-sensitive to these pollutants in their home. Most of the time we find that no filter or a cheap (99 cent) filter is being used or they have serious duct leaks in the system. If you are hiring a cleaner make sure they are using professional cleaning equipment which will consist of a rotating brush system and a vacuum source. Be highly skeptical of the contractor with no branded system or the guy who shows up with just chimney brushes and a shop vac. He will not be able to reach around all the corners or all the runs in your system and he will be taking your money for a superficial cleaning at best. Only trust a company that offers VIDEO inspection and more importantly.... a contractor who repairs, installs and seals ducts if a problem is discovered or heaven forbid, created. Good luck and get your ducts sealed if you do have a leak! It is one of the greatest energy losses to a home other than being poorly insulated.
My vent covers have lots of mildew. They look bad! I live in a very humid climate in a condo. The handyman here has offered to take those down, wash them, sand, & then spray paint them with a mildew resistant paint. He said that he will leave them off overnight to dry. I am wondering if this is safe to breath the AC blowing out into the open all night??. ! Guess it is better than the mildew!?
My 48 yr old house (mine for the last 4 yrs) has considerable dust in the return plenum (fiber duct). I’m remodeling and recently re-sealed the return plenum AND the site-fabbed transition built when the new unit was installed, 2013. The return was leaky no doubt drawing musty, dusty air from the crawl space due to the Red-Neck fab & seal job! Pitiful craftsmanship! It took me 7 hours to fix the new transition piece. Anyway, the dust in the house is the same “color” as whats in the return duct and I’m getting way too much & too often in the house. I’ve also cleaned my coils, which were not that dirty.
Ventilation is the process of changing or replacing air in any space to control temperature or remove any combination of moisture, odors, smoke, heat, dust, airborne bacteria, or carbon dioxide, and to replenish oxygen. Ventilation includes both the exchange of air with the outside as well as circulation of air within the building. It is one of the most important factors for maintaining acceptable indoor air quality in buildings. Methods for ventilating a building may be divided into mechanical/forced and natural types.
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