We carry a complete stock of replacement Water Furnace geothermal air filters. These genuine OEM geothermal air filters are made specifically for Water Furnace geothermal air filter systems. These geothermal air filters are manufactured to fit the Water Furnace Envision units. So if you are looking for an original equipment geothermal air filter for the Water Furnace Envision unit, you’ve come to the right place.