This is the first of what will be several questions over the next few days re: the purchase of a replacement furnace/heat pump/air filtration system. Rather than bog down a thread with multiple questions in one post, I will try to go step by step so I can keep the information straight. :-))
Our current system uses a standard 1" 16x25 filter. It simply slides into an unsealed slot, so a lot of air leaks by the filter; the filter is held "tight" by the air flow through it...obviously not working very well. I want/need to have much better filtration, but am not sure how much is enough/how much is overkill and hype. Whatever furnace/heat pump combination I end up with, there will be more than enough cfm generated to handle any air cleaner I end up with.
My wife has some allergies, none of which, according to her dermatologist, are caused by my basement woodworking shop. I don't believe this totally, since her allergies seem to worsen about the time I start working to get ready for my craft show fall season. As such, any new system will be sealed, theoretically, to any return air in the basement (remember, our current system is sucking dusty air by the filter all the time). Again, in theory, the dust in the basement will not be sucked in by the new system - only the return air from upstairs will be filtered.
I don't mind maintaining a filter by vacuuming and/or washing, and I don't mind (so much) replacing filters as needed. What I do mind is buying more than I really need, or buying "snake oil" when I don't know it.
With the variable speed blower furnace I will likely be buying, I plan to run the blower 24/7 to have 24 hour filtration.
At the "top of the line," I am l looking at these, all of which are touted by their manufacturers to the the absolute best:
Trane Clean Effects
Bryant Perfect Air/Carrier Infinity
Lennox Pure Air
One step down in cost/complexity, I am looking at these:
Trane 5" Perfect Fit Media Filter (same case as Clean Effects, just media only)
Bryant Preferred EZ Flex/Carrier Performance EZ Flex - either 10 or 16 MERV
Lennox EZ Flex
Question 1 - In actual everyday performance, not in mfg. specs, will I notice a difference in performance between the first and most expensive category (Pure Air, etc.) and the "filter only" units in the less expensive category?
Question 2 - Within each type, which would you install or recommend for your own house under these conditions? Why?
Thanks so much for your help. I have been absolutely impressed with the tone and quality of the answers you folks provide here...information, not "---- has always been junk" like I have found on so many other sites.