First Co 18HBX air filter size

Filter size18×20×1

The First Co 18HBX takes a 18×20×1 filter in its built-in filter rack.

Is this your unit?

The model number is on the label on the side of the unit or inside its front panel. It starts with 18HBX. First Co units are common in Florida condos and apartments.

Not sure? Take a photo of the label and we'll read it for you.

If your filter isn't in the unit

Many closets have the filter behind a grille on the door, wall or ceiling instead. That one is sized by the grille, not the unit. The size is printed on the filter's edge, or you can photograph it on our home page.

Size from First Co's product specifications. If it doesn't fit, our fit guarantee sends a new one free. Caliper isn't affiliated with or endorsed by First Co.