Here's my school of thought--if it aint broke, don't fix it. If you're having a dust problem in the house, the first place to look are the filters. Yes, dust collects in the ducts for a whole lot of reasons, but it doesn't necessarily get into the house from there, it stays in the ducts unless disturbed. That's how the ducts GOT so dusty in the first place. BUT, if you're highly sensitive to dust and you've already thoroughly investigated the filters issue and maybe even installed an air filter in your home (they can make a huge difference), then maybe spending the money on the duct cleaning will be worth while. To me it would depend on if I had a dust problem or not, and if I thought duct cleaning would solve it. If I didn't have a problem, then to me it seems like a waste of money to have something done that may have a negligible effect. But I'm not dust sensitive, so that would be the deciding factor for me. BTW, I run an air filter in my basement and it helps a lot with dust, I can compare that to the upstairs without the filter. To me, that would be a better investment if I was worried about dust in the air. But if your mom isn't experiencing any problems, then I would say it is just an unnecessary sales pitch. It would be difficult to make an across the board recommendation for something that may only help in certain circumstances. I say, let sleeping dust lie! :) But if your mom is uncomfortable with the dust in there, and has the money to spend, go for it. Somebody had to have jobs in this economy, might as well be duct cleaners! :)

The condensate collects inside the air handler where the evaporator coils are, you should have seen the pan and any tubing. There must be a pump that takes the water outside? The only connection between the outdoor coils and the indoor air handler are the refrigerant lines, and they are sealed, with liquid/gas refrigerant inside. Nothing for you to smell there unless there is a leak, and then your AC would not be working. I’m guessing as to the configuration of your system, outside condensing unit (heat pump?) and indoor air handler with duct work that goes to various rooms. Using my imagination, I have no idea what you actually have there. How did the AC guy clean the coils? Did he use some kind of chemical that you might be smelling? Maybe close to the garage wall? Hosed it off? If he used a chemical, can you ask to smell it? Does the upstairs system that you don’t use have it’s own condensing unit and air handler? I’m not an expert on this, I just used to work for an HVAC company many years ago, not as a technician though. Maybe someone with another idea will chime in.

The biggest problem with HVAC zone systems is knowing when to choose it as a solution and when not to. Some HVAC companies it's about "sell, sell, sell" whether or not it works... there's more money in "sell, sell, sell" --- when it's only about money? So does the comment above mean I do it for free? No. If you think that you are reading things that aren't there. New construction? best to choose separate systems 9 times out of 10. In order for a zone system to work, you have to know what you are doing. Most HVAC companies staff (the techs they send you) are 20-30 year olds. How much practical experience could they possible have? It's best for HVAC zone systems to be an elegant solution. A HVAC zone system is a tool in the tool bag. Not all homes are suitable for zone systems. Some homes there is no other way, and in some cases complications to those problems will make an HVAC zone system design possibly more prone to problems. You have a problem now, do you want more problems. These decisions among others are decided "in person" --- so considering that becareful what information you decide upon from the internet. Just because it's here doesn't necessarily mean it's true. That said: Depending on equipment level chosen, how many different floors you have in your structure, how much room you have available... will all be factors that make you decide one way or another. From there it's in your best interest to pick a contractor that is skilled: especially when it comes to HVAC zone systems. (there's a lot of garbage out there.) (click to enlarge if necessary) I service the Katy, Texas area.

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