Only if you change it when it is dirty. If you expect to not have to change the filer as often, forget it.

Use the pleated one on the right. it has more surface area and the media is denser. those glassflos filters like the one on the left are less restrictive but allow finer particles thru. and no it wont affect your elec bill if maintained properly

I use NaturalAire Standard pleated filters, MERV 8. The higher the MERV#, the smaller the particles that it filters, but the more restrictive it is. I stopped using the cheap-o blue spun fiberglass filters several years ago when my a/c coil froze up on the hottest day of the year. The cause was reduced air flow across the coil because it was dirty - the cheap filter allowed too much dirt to pass through and accumulate on the coil over the years. Once I cleaned the coil and starting using the pleated filter, there was never a problem again with freeze-up. I get a 3 pack from Home Depot for $7. I change the filter every 30 days even though the package states that they last "up to 90 days".

In my opinion, the people that want permanent filters are killing thier systems early. The more restrictive the filter, the harder the HVAC works. If you need a sterile environment, a simple filter just wont do the job. You need much more equipment. To even reduce the dust in a home that has hard floors requires constant cleaning, not a half as*ed filter. Filter manufacturers want to sell you a filter. The more money they can charge, the better it is. But to properly filter an environment, the filter needs to be changed much more frequently than 6 months or a year. With hard floors and moderate foot traffic, probably once a month or every 2 weeks would be better.

I had a cleaners that required filter changes every week. They would only spring for every 2 weeks, so I cleaned the coil every other month. They needed the HVAC 10 months of the year. The filter did not keep the dust down, but only tried to protect the coil.

A spin on the same question. I contacted my air conditioning manufacturer about getting dimensions to buy a pleated paper replacement and the response stated: "The filter shipped with your unit is unique to our product and can only be purchased through a dealer. Our filter material withstands a high face velocity air movement over a smaller face area. The media is reusable, and can be washed by hand in 'cold' water. The disposable filters found in retail outlets are low velocity... We do not recommend the 1" pleated ... style after market filters. Their pressure drop is extremely high, and causes high static and low airflow."

So, do I keep using the old, awful reusable filter (that does allow air to get to the front of the house -- dirty air that is) or do I ignore the warning and buy a MERV 12 paper filter and be sure to change it often? Or, do I buy a MERV 6 or 8 paper filter that advertises "Excellent for high-velocity systems and maximum air flow." Who to believe? What to do?

I don't know much abt filters, but I am about to have a complete system installed and all bidders are including the 5 inch media filters. An HVAC friend (of old school) told me not to get the 5 inch ones bec they are very expensive (abt $25 to $30 each)and you can only buy them from the dealers.(found $20 ones online). Bec they are dense, he said that the air flow would be affected and my system will have to work a little harder.