I have a few customers who love the hogs hair filters and cant be talked into anything else.
I recommend that they be washed monthly and be replaced yearly.
I also use the wire used to hang suspended ceiling grid as reinforcement and do not recommend any kind of a coating as it defeats the stacking properties of the filter media.
We've been doing so much,for so long,with so little, that now we can do almost anything, with nothing at all.
I've had hogs hair filters in my own home for the last 5 to 7 years without any problems at all. Blower wheels and motors clean,evap coils clean, duct work clean. If it's junk, then it's good junk . Just clean them monthly and there won't be any problems.
The minimum that we use is the Medium Efficiency Pleated Filters. I just dont like those hog hair filters. Its too coarse. And after a coupla washes, it gets very flimsy.
Life is like a jar of jalapenos. What you do today might burn your ass tomorrow.
Washing hog hair filters does break them down and make them flimsy. I always recommend monthly vacuuming with a once in a while rinsing if they get stacked with dirt.
I also do not recommend using a filter spray on anything but metallic filters.
...seek, and ye shall find;..
So always seek the Truth, not just what you want to believe to be true
Ecclesiastes 10:2 NIV
The lentgh and type of material used for return(duct board or lined duct,compared to bare metal),plus the filter location has a lot to do with how "good ' the filter needs to be.
When you have ducted returns that are long,and the filter at the indoor unit,a lot of the small particles of dirt/dust will collect in the return duct before ir gets to the filter.
If you have an indoor unit with a short thru the wall return,more stuff will make it to the filter,so you have more of a need for a better filter.
Filter grills will not filter any air from duct leaks in the return duct,and all the stuff from the house gos into them.
chase me down and force me to take a hogs hair filter.Worthless as tits on a boarhog.You would have to have a spotless house inorder to use one, and clean the evap coil frequently.Granted they don't harm airflow,due them not stopping alot of particals.A cheapy blue toss-away is better IMO.
If everything was always done "by the book"....the book would never change.