too many conditions to consider

Housekeeping, ductwork, CFM, operation time, outside air, .......

Without pressure sensing equipment, optimum time is not easy to guage.

1-2 times a year is normal

Yeah, they recommend 1-2 years. I have the same model on my 3-ton heatpump system. My ductwork is extrememly tight. After the first year, I changed it out and the filter was extremely clean looking. It was slightly discolored but that was all. For $20, I don't mind changing it once a year even if it could have lasted for another year.

I couldn't imagine using the same filter for 2 years for most ductwork systems. I had my ductwork cleaned (and got lucky because I think they did a good job), and I personally think it's helped because when I change my filter every month or so it isn't immensely dirty.

Thanks. I changed one after 15 months and it wasn't all that dirty, mostly discolored like you said. I guess I'll stick with a year between changes, right after spring pollen season.

If you get a reusable furnace filter you can wash it whenever you want, without fear of spending so much on replacement filters. The initial cost is a lot more than a disposable one, but most pay for themselves in about a year if you're replacing them 3 or 4 times a year.

It's also a little more green, which ought to make you feel good.

Here is a link that might be useful: Washable filters

On the washable filter posted, with a MERV rating of 5, it's not even 1/2 the filtering efficiency and about 10% of the loading capacity of the Aprilaire filter we were discussing.

No thanks

Hey Z, have you seen the upgrade kit and the new media for the Aprilaires?

I looked at the system online (pics and video) and frankly, can't see it. Media is MERV 13 and pressure drop is a little higher.

To me, it doesn't look like it would seal very well.

AM

V,
Curious, a retrofit?

Got a link?

Oops - I'm sorry, but I posted on this topic before I saw this thread (I should know to search first, but I forgot). Anyway, I am also wondering about the upgrade to MERV 13. Here is a link:

http://www.iaqsource.com/product.php?p=aprilaire_1213&product=172699

Thanks.
Lynn.

Interesting, although they don't seem to publish any performance.

If you were to use a standard MERV 13 filter of that size, it would be 0.1 resistance at 300FPM or about 1050 CFM.

Most applications can handle that, which also puts you into the very low 90's for efficiency.

There are other manufacturers of replacement filters for the Aprilaire unit such as AAF and Indigo. I know Indigo's A/A unit is a MERV 11.

I donÂt care for their rack though, looks cheesy and would be concerned about bypass.

As an FYI, I know many friends in industry that have gutted the track out of their A/A unit, add some foam to door and back, along with a gasket at top and bottom and use a commercial pleated cartridge filter sold by the case in my industry, with many choices such as Flanders, Precisionaire, American Air Filter and so many others.

Z:

Here's a link (not the official Aprilaire site). The upgrade consists of hardware which is installed inside the housing, plus a new (improved?) MERV 13 medium. From looking at it, I question the sealing as there is just a narrow (~1/2") strip of low-density foam at the back of the housing, and nothing added, top or bottom.

There is a short video at this site: http://www.comfortgurus.com/product_info.php?products_id=1418

V

Yes I watched it, see comments above

So, besides the doubts about bypass issues, does anyone have any concerns about increased resistance adding burden the the HVAC system?