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.

Question: I was recently told that I could put (4) 1” inch filters together and use as a replacement for the expensive 4 inch pleated filter in my Aprilaire Spaceguard furnace filter system.

It is never a good idea to stack filters in this way.  It restricts air flow and can cause the air conditioner to ice up, among other things.

Any savings would be quickly lost due to decreased equipment efficiency and possible service calls.

Problems related to restricting air flow.

• Reduced operating efficiency
• Increased operating costs
• Evaporator coil icing up
• Reduced air flow to the home
• Longer run times
• Filters could be sucked into the fan causing damage
• Liquid refrigerant flooding back to the compressor
• Possible equipment failure

If the cost of the filter is a real concern, you could possibly install a 2 inch pleated filter into the Aprilaire Spaceguard furnace filter system.  As long as the outside dimensions are the same as the Aprilaire filter it should work.

When installing the narrower filter make certain that it is installed against the down stream side (toward the air handler) of the Aprilaire unit.  This way, air flow will help to keep the narrower pleated filter in place.  This will only work if the filter is mounted in a vertical position.  If it is mounted horizontally, this will not work and you will have to figure out a way to hold the filter in place.

Nordic Pure Anti-Allergenic Pleated Air Filters Half the price of most leading brands!