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Geothermal Filter Sizes


No matter what geothermal filter you need, we have it in stock and ready to ship. Choose your filter's width (long side), depth (short side), and thickness using the size selector below. Further below, the geothermal filter size chart will help you choose the appropriate size and complete your purchase fast.

Filter Size

Available Geothermal Filter Sizes and Types

All Filter King's Geothermal Filter Sizes are Proudly Made in the USA

As a US-based air filter manufacturer, Filter King produces and assembles all of its components in a facility in Alabama.

We provide a 30-day money-back guarantee on any furnace filter size because we are so sure of the superior quality of our premium filters. If you contact us within 30 days of your purchase and are unhappy, we'll be happy to provide a refund. Oh, and we offer free shipping when you purchase two or more filter sets.

Geothermal Furnace Filters

The geothermal air filters for your furnace will also need maintenance to avoid incidents. The air pumped into a filter heats up before going through the filtration process, and the cleansed air is then distributed. If your furnace filters become dirty, the resulting airflow could cause heated air distribution issues. A furnace is in danger of severe damage when the unreleased airflow causes temperatures to rise. New air filters also prevent blocked airflow from causing temperature problems throughout a system.

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Why get into trouble buying replacement filters every month when you can get us to do it for you? Our simple and scheduled ac and furnace filter delivery service may be what you need. Swap your ac/furnace filter on time, every time! We have a wide variety of sizes to meet your every need.

Questions about geothermal filters?

The ideal air filter for a geothermal heat pump is one that provides a balance between efficient airflow and effective filtration. Look for filters with a MERV rating between 8 and 13. These ratings ensure that the filter can capture fine particles, including dust and pollen, without restricting the airflow necessary for your geothermal system to operate efficiently.

Changing geothermal air filters is a straightforward process:

  1. Turn off your system: Ensure your geothermal system is turned off to prevent unfiltered air from circulating.
  2. Locate the filter compartment: This is typically found near the return air duct or the air handler.
  3. Remove the old filter: Slide out the old filter. Note the size and MERV rating for replacement.
  4. Insert the new filter: Slide in the new filter, ensuring it fits snugly and the airflow arrows on the filter frame point in the direction of the air flow.
  5. Turn the system back on: Once the new filter is in place, you can turn your system back on.

It’s recommended to check your geothermal air filter every 30 to 60 days. Factors that might require more frequent checks include:

  • High pollen counts in your area.
  • Pets in the home.
  • High household dust levels.
  • The presence of smokers in the household.
  • Continuous use of the HVAC system.

If the filter appears dirty or clogged upon inspection, it should be replaced to maintain optimal air quality and system performance.

Three main measurements are used to indicate the size of a geothermal filter. A Filter King brand filter's cardboard edge has little numbers printed along it that indicate the filter's length, width, and depth. Other filters, however, might not have this information readily available, and you might have to look for the measures yourself. When doing so, look to see if the filter is square. If it isn't square, the measurement for the smallest size side comes first, then the next, and lastly, the depth measurement. The proper size is demonstrated by the dimensions 28x30x2. When ordering new air filters, round the measurements up to the nearest whole number from the actual sizes. This rounded measurement is the nominal size and matches the right filter to its fitting air filter slot. You can order a new geothermal filter that easily slides in and out of place using the nominal size.