Be sure to change your heating or heating/cooling system filter when it is most recommended by the company who makes the filter or by your local dealer or repair person.  It is very important not to use an excessively-clogged filter because this will restrict air flow to the blower motor and the motor may burn out.  It would be an expensive repair to replace the blower motor, and this repair could be avoided by changing the filter at the proper intervals.  If you have a permanent-type, electrostatic filter, then this type of filter, of course, would need to be cleaned when necessary.
     For health reasons, in a duct-type system, be sure to consider having all your vents and interior of the ductwork cleaned, if an inspection shows that the vents and inside of the ducts are dirty.  Getting the opinion of a professional would be a good idea.
     Also, consider purchasing a good quality air purifier, even if you think it would only be used occasionally.  Discuss this subject with a professional if you are not sure if purchasing one for your home or business would be somewhat to very-much needed.       
Residential and business heating and cooling system filters  / interior air quality   image
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