Close up of firty filter

Your furnace and air conditioner both have filters to protect them from debris and to help keep your air quality high. If you have a humidifier, dehumidifier, air purifier, or other HVAC appliances, chances are that they also have a filter. It may be challenging to keep up with all of these filters and when you’re supposed to be changing them out. In this quick guide, we’ll show you when your HVAC filters should be changed in general, and signs that your filters might require something else. 

When Should I Change my HVAC Filters? 

HVAC filters should be changed on a regular schedule that, in part, depends on the thickness of the filter itself. Once the filter is too full, the debris that has been captured in it will limit airflow to the appliance. This can reduce the effectiveness of the appliance and even cause long-term damage. So, you need to change the filters when they are full.  

  • One- and two-inch filters need to be changed every three months 
  • Four-inch filters need to be changed every six months 
  • Five-inch filters need to be changed every twelve months 

However, that’s only in average conditions. There are many things that may change how often you need to change your filter. Homes that produce more dust will fill the filter faster. Homes with pets will do the same with pet hair and dander. If you smoke inside, the filter should also be changed more often. 

Plus, your own personal needs can dictate changing the filters more often. If you have respiratory conditions, like allergies, asthma, or others, then you may benefit from cleaner air. Changing the filters more often can help with that. Although, you may also want to look into other solutions to help, such as a HEPA filter.

If you need to change your HVAC filters contact us today.

Signs Your Filter Needs to be Changed 

You can check on your filter to see how well it is faring and whether or not it needs to be changed: 

  • The filter is covered in thick grey debris 
  • Your home is dustier than normal 
  • Your allergies or asthma are acting up 
  • There is a burning smell coming from your HVAC appliance 
  • The heating or cooling is running more than you’d expect 
Calendar and clock on blue background

When to Change the Filter? 

The time of year you change the filter also matters. Ideally, you’d change the filter on seasonal appliances, such as your furnace and air conditioner, right before you turn them back on for the season. This ensures maximum performance. 

Not sure if your filter needs to be changed? Or, just looking for a professional to handle the process for you? Reach out to Whitfield Climate Care to get help. 


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