Entries from February 2009 ↓

Question: I have a Honeywell electronic furnace filter on my furnace. The power panel failed and the unit is very expensive to replace. However, I can install pleated air filters in place of the original electronic cells. The filter size is 20 X 25 X 4 inches thick. As a temporary measure, I have installed 3-1 inch thick MERV 8 air filters in parallel into the filter opening.  How does the MERV rating change when the filters are placed in parallel? Is what I have done a good solution? If not, what would you recommend that I do?

I would remove two of those 1 inch pleated air filters ASAP. Installing filters in this way has a very negative effect on air flow and reduces equipment efficiency greatly. Take a look at your air handler to see if there is a place to install a 1″ filter. Most air handlers come equipped with this filter rack.

Take a look at the pictures on this page “where is my furnace filter” if you are not sure where to look. If you can’t find a place to install a 1″ filter, you can get a 20 X25 X4 MERV 12 filter at NordicPure for a very reasonable price.

An air filter change indicator can potentially save you hundreds of dollars on replacement air filters and can even lead to reduced operating costs for your air conditioner, heat pump or furnace.

How is this possible?

• Change your furnace filter or air conditioner filter too often and it’s like throwing money away.
• Wait too long between filter changes and equipment operating efficiency begins to decline.

How often should an air filter be changed?

Manufacturers often differ in their recommended filter change frequency. Some say every month, some say every other month and others recommend every three months and that’s only for 1 and 2 inch filters. If you use 4, 5 or 6 inch pleated air filters, recommendations vary from 3 months to a year.

Filters are expensive, especially the efficient varieties and the 4, 5 and 6 inch types so you don’t want to be changing them more often than absolutely necessary. It’s very difficult to know when a filter has reached the point where it is better to change it than to leave it in the system.

Manufacturers can’t really tell you because they can’t possibly know the conditions in every home, not to mention every geographic area. There are just too many variables to consider. If you follow a set schedule for your filter changes you are probably not getting the best value from your filters.

Leaving an air filter in your heating or air conditioning system too long costs money

If you don’t replace you air filter often enough it begins to impact air flow and causes equipment operating efficiency to decline. A decrease in operating efficiency translates to higher operating costs. This means higher energy bills and nobody wants that either.

If left in a system long enough, a dirty filter will cause air flow restriction and can cause evaporator coils to ice up, heat exchangers to crack, longer run times and other equipment troubles that may require a service technician.

So what’s the solution?

Installing an air filter change indicator eliminates the guessing from filter change schedules. You won’t be throwing money away by changing filters too often and you won’t be wasting money and dealing with the potential problems associated with leaving an air filter in too long.

More about air filter change indicators.

Compare Filtrete and Nordic Pure pleated air filters

Question: I would like to save costs by getting a washable air filter, but it seems that none of them can get a MERV over 8, and I’d like something with a MREV of 11 or higher since we have allregies in the family.  How does Boair or air-care-filters.com filters compare to the filtrete ultra allergen. If I need to get a disposable, is the Nordic the best priced disposable filter?

You are correct about washable filters. Although they don’t have MERV ratings they perform close to a MERV 8. Although washable filters have their own positive characteristics, if allergies are a concern for you I would recommend high efficiency pleated air filters.

I did some quick investigating and this is what I found when comparing these pleated air filters

- Filtrete Ultra Allergen filters are $13.88 at Walmart and they have a MERV rating of 11 (I used Walmart because they usually have good prices)

- Nordic Pure Box of 6 is $48.97 which works out to $8.16 each and they have a MERV rating of 12

Both of these pleated air filters enhance the performance of their filters electrostaticly.

Nordic Pure and Filtrete filters don’t support the growth of bacteria, fungi, mildew or mold.

Nordic Pure filters have a higher MERV rating and they are much less expensive than Filtrete Ultra Allergen filters.