Jeff came by today and cleaned the ductwork. We do this at least once every year. It's supposed to be good for the heating system, and I guess it would. But the most important benefit is that much less dust in the system.
Think of it this way: even though the dryer has a lint filter, we still need to clean the exhaust duct. You know, one of those flexible, coiled tubes that comes out from the back of the dryer, goes up the wall and outside. We have a pretty good filter that we clean each and every load. But a couple times a year, I take down the duct and compress it, while running a vacuum hose right near my face. And each and every time, the thing is so full of lint, it comes out in clumps.
When we first began hiring Jeff's Heating Service, he arrived with a huge vacuum bag that subsequently filled with crud, more crud, and (Ye Gods!) dead bats. Now, years later, he doesn't use the bag, and what's vented is barely visible, let alone polluting. And this is a house with three full-time cats, a part-time dog, and two smokers (one full-time, one occasional) every day. This is a 20-hour household; there is someone awake and busy in the place at least 20 hours out of every 24.
Of course, I know what would be good to eliminate; but I am crazy about all of the above polluters, if not their pollution. So very heavy air filters and regular duct cleaning is as good as it gets around here. The asthma's a relative Johnny-Come-Lately to the mix. I put up with all the polluters the same way I put up with Dee-Dee on my lap while blogging: eventually, I blow up and out they all go for a while. I can be scary. Or at least I can be quite a nag.
But the duct-cleaning is a nice gift to me. Now, I just wish I could find and justify the cash needed to have the windows professionally cleaned!