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.
We moved to a house built in 1965 from a 1915 house with a dirt basement. Against what I anticipated, the 1965 house was much dustier. It was like felt on top of everything. I cleaned and cleaned and it did become less dusty over time. We then found out a cat lady with over 2 dozen cats lived in the house in the past. We then had to get our furnace replaced and I was able to look down some of the duct work, the dirt and debris was 3-5 inches deep. Additionally, the basement ducts were entirely plugged with debris including dirt, seeds, ants, toys, etc. I had already removed what I could from those. We had our ducts cleaned last year, and the dust in the house is greatly reduced. Also have lost the runny nose I got after moving here. There are duct cleaning con artists out there, but ours did a good job.
There is a lot of good, general information in the article. As with anything, the homeowner should do their due diligence in getting enough information to make an educated decision. Should duct-work be cleaned? YES! Does it need to be cleaned annually or even every second or third year? Not necessarily. It all depends on a bunch of variables. You're right that a well designed and balanced system will deliver the right amount of air flow, but sometimes conditions outside the home/business, make it a necessity to get the ducts cleaned. As for mold? NO filter is going to address a mold issue. If you have mold, you have a moisture issue that needs to be addressed. Also, in my 38 years of experience in the HVAC and sheet metal industries, washable filters are one of the reasons ducts need to be cleaned. They are no where near efficient in cleaning/filtering the air to the level that they should.
Equipment used to clean ducts varies widely. The cheaper the equipment used the more you are just wasting money. This is why it's typically not worth doing. In some situations it may be beneficial, but only after determining and investigating the duct system. This should be done by a licensed HVAC contractor and not a duct cleaner that typically do not hold and HVAC license. (Duct cleaners aren't required to be licensed in HVAC in many areas.)
I turned on the AC when he was finished and immediately saw black fuzz balls the size of marbles come out of several of the registers. He said that was expected since everything was shaken up. So much for describing the service as cleaning. I paid him and sent him on his way. I cannot imagine that this type of service is worthwhile in anything but a new house. Apparently in old houses such as mine I can expect that using a whole house humidifier in the winter followed by a great AC can loosen the soot. Maybe this is to be expected for the first few weeks of summer each year. I now have lined the inside of the registers with cheesecloth to catch the fuzz. I’ll see if it stops after a couple of weeks.
The short answer is yes, duct cleaning, done right by a reputable company will help with the smell. It is likely though the smell is coming from another source, ie the crawl space. It could also be that another rodent is dead in the duct work. A visual inspection would be in order to check for any breach in the duct system. A duct pressure test would be able to tell you how much air is leaking from the system over all. A hole large enough for an animal to enter would loses a great deal of air, over 300 CFM. It would be worth looking into having this test done and it should cost around $200. Cleaning the air handler and evaporator coil will greatly improve the performance of the air conditioner. Dirt and dust on the evaporator acts as insulation and reduces the amount of cooling done be the coil. Any quality duct cleaning should include cleaning the air handler and coil, and the tech should allow you to watch him perform the work as it is done.
I did the $49.00 Groupon they just left. Basiclly all they did was stick a shop vac type hose into the vent supply and one return. I also had the dryer done. the person in charge pointed to the main return inside my humidifier and said it needed cleaning. I explained that I was in facility maintaince and would deal with it myself. After that they finished the vac and didn’t try any other sales pitch. I should have read the reviews before I bought this wast of money and time.
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.
You may be familiar with air ducts that are constructed of sheet metal. However, many modern residential air duct systems are constructed of fiber glass duct board or sheet metal ducts that are lined on the inside with fiber glass duct liner. Since the early 1970's, a significant increase in the use of flexible duct, which generally is internally lined with plastic or some other type of material, has occurred.
I just had my blower module replaced because my AC coil was frozen over. The underside of my coils had a thick mat of dust because I had never had it cleaned. I cleaned it myself by using a soft brush attachement on a shop vac. The inside of the blower appears to have a white/green growth, and I am sure the ductwork of my 30 year old house can’t be in good condition.
Although i love to burn candles, depending on the type your asking for problems big ones! At work one day i had been talking with co workers about these black shadows that were appearing on my ceilings and higher wall areas. They seemed to in the corners and along the stud supports , i could even see what i thought to be where all had been nailed. There would be dark shadows perfectly straight across my ceiling and then real dark circels every few inches within the lines. I thought it was the propane heat but learned quickly that oil heat will do that but not normally propane. A co worker brought me a magazine with a huge article about candles and what actually burns off them when lit, an ashy soot that is attracted to the areas on walls and ceilings that omit the most heat or warmth, of course where the drywall and studs meet and corners of the room. Its been about 8 years since i painted the entire house. I started bending to my love for candles again in the last 3 years, surprise i will be spending part of my summer re painting again!! No more candles ,well maybe at the holidays LOL
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 was told that 15 out vents would be cleaned and one main vent. the guy came over and gave me an estimate of $500. I had acquired a groupon for $49. the guy said just doing the out vents and one main vent would accomplish nothing. Now I am in dispute with the groupon people for a refund which they won’t give and have to go ahead and waste the money and let them do it. Is their doing the 15 outvents and one main one going to accomplish anything?
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.