The A/C System Cleaning and restoration industry has become a very lucrative bait and switch industry that many Carpet cleaning companies, Maid services, as well as plumbing or handyman service companies are adding on to there services. These add-ons are not fully certified, trained or even have any experience in the HVAC industry. These companies are the reason prices and quality of work are all over the place. If you are looking to make a smart decision for your home a professional Duct Cleaning service will protect you for 5-7 years. This info comes from NADCA (National Air Duct Cleaning Association) which is the closest thing to a license we have for duct cleaning. They have a great site that explains this process and pricing much more in depth and factual than what has been written here. This organization is working very hard to get these bad companies exposed and out of this industry. So in saying that do your research! Green Duct Decontamination is a certified company with certified technicians that take this work very seriously. We can not have these low rated unprofessional companies paste a bad name for an entire industry. Stay away from anything under 250$ for a full duct clean this is not feasible, go look at NADCA.com and you will understand why and what these companies are doing to rob you of your dollar.
One of the best ways to know if your ducts or vents need to be cleaned is to just check them. Your eyes will be able to check for indications of mold, dust or pollen buildup. You might also be able to smell the presence of mold, which would be a clear indicator. Ductwork will have some buildup of dust, since the return registrars pull air back in. However, this doesn't mean your ducts have too much debris, and you can easily clean them with a duster or vacuum.
Capacitors -- Capacitors help your HVAC motor start from a standstill. Over time they can weaken. As they weaken, they cause the motor to run hotter. This can shorten the life expectancy of your motor. Once a capacitor fails, the whole motor will stop working. You usually won't notice that a capacitor has weakened until your motor stops turning on.
Despite Bergendahl's experience, Vinick says NADCA's certification standards have improved the situation. "A lot of [service companies] weren't going about it the correct way," he says. “We have an anti-fraud task force, and we’ve gone after some fraudulent duct cleaners with the help of state attorneys general.” He suggests that in addition to NADCA membership, homeowners make sure their cleaners are an established business, have appropriate insurance and are registered to do business in their state and locality.
Metal is way better than flex duct or ductboard. It gets better airflow, holds up to critters and duct cleaners. I know of no hvac company here that cleans ductwork. (there probably is one somewhere) The mfg's of duct cleaning equipment keep trying to sell us hvac people on their benefits and profit potential but most all hvac people know that unless you have metal ductwork you are NOT doing the customer any favors.
When these aren't properly maintained and sanitized, they can build up dust, pollen, and even mold. This means when the air conditioner or heater turns on, the spores are released into the air for you to inhale. While some are less harmful, people who have allergies or sensitivity to certain spores will react negatively. Plus, mold is dangerous for anyone to ingest and should be avoided by regular maintenance.
The AC contactor (relay) and start/run capacitor(s) (see illustration below) fail most often and are inexpensive. So it's a safe bet to buy and install those parts right away, especially if your air conditioning service unit is older than five years. The condenser fan motor can also fail, but it runs about $150 — hold off buying that unless you're sure that's the culprit.