Iím trying to find a good duct cleaner in Toronto.
(Iíve been living in a two story apartment building for four months and have been diagnosed with dust and slight mold allergies. I share a basement and an HVAC with the apartment below me. After researching the pros and cons of duct cleaning I have concluded that itís worth trying. My building was built in the fifties and has never had its ducts cleaned.)
Iíve interviewed a bunch of companies and have questions related to the answers they have given me.
RE: AGITATION/SCRUBBING IN UPPER DUCT WORK. One company said it will send a forward bouncing ball through my vents to blow stuff to the basement. Another said a ball wouldnít be able to get around turns in flexible duct work. (As I canít see that ductwork I canít tell what type it is.) Most companies say that blowing air down the vents is what they do. Is mechanical agitation necessary/possible on the duct work leading to the basement?
RE: AGITATION/SCRUBBING IN BASEMENT. Is a reverse blowing whipper ball adequate? One company told me that rotary brushes would a) not be a good choice in my rectangular supply ducts b) not fit in my return duct which is a panned bay nailed to the floor joists in the ceiling. Is a scorpion system better than a whipper ball? How many holes should be made in the ducts (holes for vacuum, holes for air rake) and where? My ducts are metal.
Re: BIOCIDES and COIL/BLOWER CLEANING. It seems it is not recommended to blow a biocide through your duct system. But it may be necessary to use on the air conditioner coil and condensate pan and blower? Opinions? Whatís a good way to clean a coil? With a comb? Or by blowing air at it? One company told me that an acid wash would be too abrasive for a residential coil. How about the blower? Is it necessary to pull it out of the cabinet? And insulation on the side of the cabinet?
RE: SEALING VENTS in my apartment. Methods Iíve been quotedÖ magnetic covers, plastic bags, masking tape. Pros and cons thereof? Is it common practice to clean the boot area with a shop-vac?
RE: NUMBER OF GUYS ON CREW. Advantages to two person versus one person teams? Other than time?
RE: LEAK TESTING. Do duct cleaners test for leaks before commencing work? (I had two companies come in and give me estimates. Both missed something I discovered a week laterÖ that there was a gaping hole in my return duct where a pan had separated from a ceiling return.)
RE: COMPANY CREDIBILITY. All the companies I have spoken with have at least one NADCA certified employee. They all use vacuum trucks. But the price variations are pretty big. A department store branded company acknowledges its ďpremium priceĒ. But Iím not sure after speaking with them and other companies that they have much more expertise to warrant the price difference (They came to my house for the estimate, and they have a name behind them, but does that warrant the price difference?) I want a good company to do the work, and Iím willing to pay for it (ie. no blow Ďn gos to make things worse), but aside from getting references, any suggestions on choosing a company?
RE: WEB RSOURCES. Any other forums out there where I might find more local Toronto information?
Any other thoughts would be greatly appreciated. Thanks.
-Agitation is a must. However, it is literally impossible for any method to scrub all the ducts. Much will be missed by all.
-Clean the coil by first mechanically removing heavy debris with a brush, comb, whatever. Then use good soap and rinse.
-Yes it's common to clean the boot with a shop vacuum. It's also common for some to dump that debris into the main vacuum to impress you with what they pulled out. I'd suggest vacuuming the boot yourself before hand.
-Sealing all vents but one creates a very nice vacuum on that one. It also increases the insulation and other debris that get drawn into the duct through unsealed seams as the duct cleaners clean.
-All garages have ASE certified mechanics. All garages are not created equal. NADCA certs are nice, but I'd worry more about methodology and efficacy.
Other thoughts: Read this and tell me what you think. Those would be my thoughts and opinions. However, aside from opinion you'll see something there you may have not seen yet: real science. If you want real improvement in your air quality, seal the leaks in your ducts but don't "clean" them. Every time you run your system the leaks in the supply ducts typically put the house under a negative pressure - which causes outside air from above or below to be forced in. If you have a wet crawlspace under the house, roof leaks or plumbing leaks then get those dried out. There are other real methods to IAQ improvement if you search them out.
To anyone with a long memory (not you Tom), you'll be relieved to know that I will NOT be engaging in debate with duct cleaners. There's no need. If Tom reads my editorial and still wants to do it, God bless him. I'll say absolutely nothing more unless Tom asks a direct question (or unless someone insists on impugning me personally instead of focusing on the facts).
I really appreciate your reply. Although you question the efficacy of duct cleaning, you take the time to answer many of my ďmethodologyĒ questions anyways. Thanks!
And thanks for the link to the editorial. It makes some good points. Iíve read the arguments for and against duct cleaning and I appreciate the thinking on each side. I realize that having my ducts cleaned may be a waste of money, but itís a risk Iím willing to take, an educated decision Iím making.
RE: the effects of leaky ducts on IAQ...
QUESTION: How does one test for leaks? I asked one duct cleaning company and they said leak testing wasnít their domain. I can foil tape obvious holes, but what about the ducts behind the walls? How do you know if theyíre leaking, and how do you repair them? And are the unsealed seams you mention pretty common?
RE: other methods of improving IAQ... Iím trying to learn as much as I can. Iíve read a lot on the internetÖ also a couple of books that seem pretty scientifically balanced. (ďMy House is Killing MeĒ and ďThe Mold Survival GuideĒ by indoor air investigator Jeffrey May)
At this point Iím trying to take simple, fairly cheap steps at improving things. Iíve had the carpets removed in two of my rooms, and I figured duct cleaning, which my landlord is willing to go half on, is not that expensive to try.
What Iím NOT thinking of doing at this time is:
1.installing a HEPA unit on my furnace (If I owned this building and was staying here forever, maybe, but I don't and I'm not)
2.replacing my drum humidifier with a newer, cleaner type (my humidifier is clean)
3. replacing my paper filters with an expensive electronic one (which I understand would require frequent cleaning and would be of questionable efficacy).
(The last two options are ones that a couple of duct cleaners tried to sell me on.)
Any other simple steps I can take to IAQ improvement?
Hmm. It seems a reply or two has disappeared. Hopefully you got what you needed before they were deleted.
I read the messages about leak testing and open doors. Strange they disappeared. Have decided to do the best I can sealing any leaks I can see, then proceed with duct cleaning. Irascible, thanks a lot for your info, it's much appreciated.
(Apparently the server crashed and they lost a bunch of replies posted right before the crash.)
While I disagree with a lot of the editorial posted above, I do agree that he has some relevant points. I do not personally perform duct cleaning as a service, but do see where the need is often there.
The main thing you need to insure is that the duct cleaning is not limited to the use of a negative pressure machine with a brush. There are ways to clean duct properly with good results as long as the duct is accessible. One company I am familiar with that offers this service in my area uses both the negative pressure machine and the roto-brush machine. Everything is inspected visually by using a boroscope camera while the cleaning is taking place. If they miss a spot, they know it. If there is a turn or offset that the machine cannot get through they go to that area, take it loose and clean it by hand. Trunk lines are cleaned from both supply access and by an entry point in each size section of the trunk. In other words, everywhere the trunk reduces in size a different size brush is used for that area (much like a chimney sweep uses for different sizes of flue). After the initial cleaning is done, they take each supply loose at the trunk and clean by hand at the take-off / collar as there is no way any size brush can properly clean those areas. They then clean and sanitize all registers and grills (outside), they remove the blower motor and housing and clean those areas as well. The coil is the kicker here. In many applications, it is only possible to clean one side of the coil. I think that is better than nothing, but when it comes to microbial infestation, it is not sufficient to remove mold spores permanently. The coil needs to be removed and cleaned on both sides, but even then you have the inside of the coil to worry about. Really the only way to properly clean a coil is to destroy it by cutting it open, so we are left with no choice but to do the best we can. The last thing they do is seal the ductwork. It really is funny that the majority (and I mean 90%) of the jobs I go on, have some obvious flaw that has been there since installation. Sealing ductwork with hard-cast at every joint is about effective as anything I have seen.
The way the company I referenced above cleans duct work is by far the best I have seen. The problem with doing it this way is cost. The $100 - $600 pricing I saw referenced above would not let this company even be in the running. To do it like these guys do has a considerable cost, but it is still cheaper than tearing out and redoing the duct system. I do not see any point in cleaning ductwork unless it is done in a fashion that will give you effective results. If you are just looking to throw money away, I'll be glad to let you throw some my way.
In conclusion, I disagree with the above poster that duct cleaning is a rip-off. I do agree that the majority of duct cleaning companies out there do not do it correctly, thus creating a rip-off situation.
Just my .02,
I am an air duct cleaner and own my own company. Deciding who is right for you may take considerable time and I commend you for doing your homework first.
A helper saves time, sometimes! To be NADCA certified, a company only has to have one certified tech on staff, but unfortunately that person is not required to be present on any job. Simply having one on staff is worthless if the person cleaning your system has had little or no training or experience. Being certified is no great achievement either and I passed their test two months before cleaning my very first system. I've since let it expire.
Few systems can be thoroughly cleaned with a vacuum-operated rotating brush. The list is long, but vent opening size and obstacles inside limit their effectiveness. The soft bristle brushes would be best suited in similar size flex duct and/or duct board with a height not exceeding their diameter and a width not exceeding twice that diameter. Any small telecom wires run inside those ducts would likely be history too! Attaching a camera to the end of their hose, gives the viewer an impressive view of the dust generated by the brush, but fails to show the dirt being left in front of it. Its also rare to find a system that only has dust in it. Most contain construction debris, paper, and other objects that will readily plug the slots on their hose.
I have 3 vacs - a 20hp gas portable, a HEPA filtered electric portable and a 56hp diesel truck mounted vacuum. Unlike glorified shop vacs, these can't be hauled around in the trunk of a car and all were professionally designed to clean air ducts, not sold as an add-on to the carpet cleaning industry.
My stainless wire brush system is powered by a drill and used in combination with one of the above vacs. Those using reverse whips only, typically clean everything from the basement. Any duct that is not readily accessible, doesn't get cleaned and there are no magical ways to get that tool to travel even a few feet down a main and make a precise turn into a branch duct from a remote location in the main. Nor has there been a vacuum built (that won't collapse the ducts) that is powerful enough to suck the dirt out of the dirts. Simply blowing air thru them doesn't do much either, in fact there is no single tool made that will clean everything, 100% of the time. For that reason, I have both the Scorpion and Viper cleaning (air agitation) systems. Individually they are great, combined they are excellent.
I attach an 8", 10" or 12" suction hose to the supply and return side of the system. The two sides are isolated to prevent dirt from being drawn thru the heat exchanger or indoor coil and each is cleaned separately. Before cleaning the return side, I remove the blower (disassemble and clean it) and attach the suction hose there. This also gives me direct cleaning access to the bottom of the primary and/or secondary heat exchanger. Please Note: In some areas, a license may be required to disassemble and clean any portion of the air handler. In others, its simply more profitable to ignore them. Before cleaning the supply side, I access and protect the inside coil (or exposed top of the heat exchanger) and will hand vacuum, brush and/or chemically clean the coil when done. All holes are sealed air tight and their covers conform to industry standards for type of duct material you have. The number required is determined by need, but typically a single 8" hole is needed in the supply side for suction and 1 or 2 - 1" holes in the mains for my cleaning tools.
All vent covers are removed and their respective openings cleaned. Rather than trying to remove heavy debris with my vac from those openings, I will use a small shop vac. A 3/8" air line is run to each vent opening, & the air-powered cleaning tools attached to small flexible rods are inserted there to clean the smaller branch ducts. A similar method is used to clean the mains and plenum. Cardboard is used to cover the vent openings. Not pretty, but cheap and they're disposable. During cleaning, it is reasonable to assume that the vacuum will pull outside contaminants into the system thru any existing leaks, but is just as likely that same vacuum will remove those small particles from the system too.
Before and after pictures are easily manipulated and many use them to show the dirtiest return first and the most easily cleaned supply vents afterwards. Those using glorified shop vacs also have the opportunity to "load" their vacs with an impressive amount of dirt to show you later. To verify cleaning, I place a wireless infrared video camera inside the duct work and face it into the exiting air stream. A monitor is carried with me to each vent and eliminates my need to guess when each run is clean. While it may not be possible to remove 100% every time, watching this lets me be confident that all lighter (airborne) particles have been removed. Anything remaining won't likely have an affect on your air quality either.
I don't believe in the indiscriminate use of chemicals and that includes sanitizing. Mold can only grow when moisture is present. Correcting its source is critical to preventing future growth & once done, thorough cleaning will remove anything left inside. Many claim long term benefits from sanitizing, but most use a product that is only effective when wet. Once dry, it actually becomes a contaminant as can any other materials (encapsulants, sealants, etc.) which are applied to the inside of your system.
Notice that I said both the negative pressure machine as well as the rotobrush need to be used. I think the 2 machines actually compliment each other very well. Visual inspection is key.
I wouldn't have any problem recommending you to a do a duct cleaning for one of my customers. I, do however disagree with you about the the use of biocides. You may be right, that it is the lesser of 2 evils (would you rather have Mold or VOC's). As I stated earlier, the coil area is more than likely your source and needs attention. If mold is found, you need to remediate it.
I used to work for a small air conditioning company that did duct cleaning. For 6 years I was on every duct cleaning we did, and from personal experience I honestly can say I don't believe a duct cleaning does any good for getting rid of mold. It may increase air quality, some of the customers said they could breathe better. You can look at it like a placibo, that being its all in thier head. You can't get all the mold and dust out of a system, you can get a good bit, but mold grows in damp places, it'll grow back. we sprayed a sanitizer into the coil, blower, and registers while in a vaccum. Even put a hepafilter in after we were done. I feel it was a good procedure, we tried ot cover all the bases, but doing that many over that period of time, I wouldn't have it done on my house. Not paying for it anyway.
All corrective action is relative to the climate that you live in, but when a system is under negative pressure spraying any chemical into it is a joke. The majority of the chemical will be removed by the vacuum and the only surfaces that will be thoroughly coated are those that are in the direct path of the spray.
Even if the chemical is applied correctly, unless you resolve the issue that is creating the moisture problem, a one time application of a chemical that only kills for an hour or so will do very little to prevent future growth. Mold spores are everywhere and they will return and flourish unless the environment inside the system is made inhospitable to them.
BBJ Environmental markets a product that they claim can prevent reproduction for up to 6 months. If their claim is true, it would be the better alternative when the moisture problem can't be readily resolved. If the problem can be corrected then thorough cleaning should remove anything that had been growing in there.
Thorough cleaning requires time, patience and good equipment, but verification is the key to doing it right.
[Edited by options on 03-10-2005 at 02:48 AM]
install a 5" thick media filter. change it ea 4 months.
seal or have sealed, the duct & plenum joints with mastic. vacuum out the boots just below any floor registers. have the blower wheel cleaned. have any open flame furnace adjusted for max effeciency, low CO, etc. get a portable HEPA unit for bdrm -- run it when not sleeping, or even then on low. be sure that water is not standing next to building -- if it is, pester landlord until fixed, or MOVE!
mold must have moisture. mold is everywhere. soap & water or bleach & water kills mold.
items not listed in logical order.
Bleach and water will kill anything and a homeowner can (however ill-advised) legally use it on their own (and only their own) system, however a professional cannot and any product used as a sanitizer must be EPA registered and labeled for the intended application.