Question: After two months of our heating slowing down, and finding it was the filters, we bought a gauge for our air filter.  3 months in a row now we’ve found we need to change our filter once a month… we have 1 small dog, have the house cleaned and vacuumed every other week and live on a dead end off a dead end, backed up to a cemetery (no traffic).  Why is our filter getting so dirty in just one month? Makes me feel like I should just go with disposable filters.  What do you think?

In late December, our house was colder than the thermostat set point for hours.  I called the oil co. for a service call.  I swore up and down it wasn’t the filter, but he kept suggesting it was, and sure enough, it was - In less than a month the filter was actually sucked out of shape.  I was so embarrassed!  But we keep a note on the attic pull down with the date last changed so he knew I wasn’t mistaken.

The next month we changed at a month, and this past month we had the gauge saying it was time to change the filter again after a month.

Hubby buys whatever he can find in pleated at Home Depot, because we have to cut them (20 x 221/4) But the tech from the oil company used what I believe you call media filter pads.

Last month I had him buy 1 because I was going to order a case online but never got around to it.  I can only tell you that he bought a 3 pk last night and it’s Natural Aire - Merv 8.

Just seems like so much dirt.  Our return is in the hallway ceiling so the dog hair probably doesn’t even get up there.

That is a fairly common problem and unfortunately it is one of the weaknesses of pleated air filters. They are very efficient but their dust holding capacity is not great. Dust is collected on the surface of the filter and can quickly become a problem.

You have a couple of options.

1)Your first option is to install thicker pleated filters in the filter rack. Rather than cut them to fit you can order custom size filters. They are available from 1 to 4 inches thick. A thicker filter will last longer because there is a larger surface area to collect dust. Of course this will only work if your air handler will accept thicker filters.

2)Your second option is to switch to media filter pads. Although media pads are not as efficient as some pleated air filters they still do a very good job. The advantage of media pads is that they have a much greater dust loading capacity than pleated air filters. Rather than all of the dust being collected on the surface area of the filter, dust is collected throughout the entire 1 or 2 inch thickness of the filter material. Distributing the dust through the entire thickness of the filter material means the filter can remain in the system longer before having the same negative effect on air flow. The dust loading capacity is much greater.

Question: I bought a package of 3 pleated air filters from Flanders. I am not sure how to install them. One side is plain white pleated and the other side is plain white pleated with a X of cardboard. Which side goes toward the furnace? What is the proper furnace filter direction?

As discussed in previous articles here at www.furnacefiltercare.com, there are many different types of filters and often it is difficult to determine which way a furnace filter should be installed.

The filter type that generates the most questions regarding which way it should be installed, is the pleated air filter. These filters also happen the be the most popular air filters for home owners. Because of this there are many manufacturers competing for market share and therefore many different designs.

To increase the durability of pleated air filters, manufacturers often extend the cardboard frame across the face of the filter in the form of an X or strips. This enables to filter to maintain it’s shape and prevents it from collapsing under the strain exerted on it when air is passing through it.

If , as in this case, there  is only one side of the filter that has cardboard across the face. That side should be facing the furnace.

More on the subject of furnace air filter direction:

Which Way Do Furnace Filters Go?
Installing an air conditioner filter or furnace filter incorrectly can have a very negative effect on it’s performance. The ability of a high efficiency filter to remove dust from the air can be drastically reduced if it is not installed properly.

Question: I heard that the use of air filters other than what was initially installed can damage the furnace. I have a Goodman MBR air handler and the Epurair filter system. Can I use any filter that is 24 x 24 x4?

The Epurair filter is a pleated air filter and you can replace it with any other brand of pleated filter of the same dimensions. Any 24 X 24 X 4 pleated filter that will fit into the filter holder will do the job.

If you are concerned about impacting air flow in a negative way, you can check the MERV rating of the filter you are replacing and replace it with a filter that has the same rating.

It is important to point out that this applies to all filters. Brand is not important. What is important is the filter rating. For example, replacement Honeywell furnace filters can be purchased through various filter manufacturers. They are made to the same specifications as the brand name filter.

Something to think about.

Millions of products, are manufactured every day by companies that you would not recognise the names of and often in foreign Countries. The brand name company then puts their logo on the product and sells it as their own.

More Information on this Topic

- Trane furnace filters This article talks about Trane furnace filters but applies to all manufacturers of pleated furnace filters.

- Furnace filter ratings, terms and definitions.

When the topic of electronic air cleaners comes up it usually doesn’t take long for questions to arise about ozone and whether it is safe or not. So due to several comments on this blog and questions I have received by email I thought I would share a link to a report I found, published by the US Environmental Protection Agency. The report should provide answers to most questions concerning ozone and any health risks associated with it.

The title of the document is "Ozone Generators that are Sold as Air Cleaners: An Assessment of Effectiveness and Health Consequences"

The topics covered are:

• What is ozone?
• How is ozone harmful?
• Is there such a thing as good ozone and bad ozone?
• Are ozone generators effective in controlling indoor air pollution?
• If I follow manufacturers directions can I be harmed?
• Why is it difficult to control ozone exposure with an ozone generator?
• Can ozone be used in unoccupied spaces?
• What other methods can be used to control indoor air pollution?

http://www.epa.gov/iaq/pdfs/ozone_generator.pdf

The table below is copied from the report for those who do not want to read the document.

Ozone Health Effects and Standards

Question: I am considering replacing my Aprilaire media whole house filter with an electronic filter.  I will be replacing my heat pump within the next few months and would probably buy a Carrier electronic filter.  I am currently using the new upgraded 15 MERV April Air filter. My service technician recently told me that based on his experience, the media high efficiency media filters do a better job of keeping the inside of the air handler cleaner than the electronic filters and the media filters require far less maintenance. He recommended that I continue using the media filter and not replace it with an electronic filter. Your comments are very much appreciated.

I would agree with your service technician 100%. In my experience, electronic air cleaners are over rated. They may be  efficient at stopping smaller dust particles but are not as good at stopping
larger dust particles. For best results use media type filters such as Aprilaire and Nordic Pure.