Fill lines differ based on what cleaning mode you use. Express clean uses less water and solution, and the fill line is near the bottom of the tank. Near the top of the clean water tank is the fill line for Deep cleaning mode.
This process changes slightly when using the Bissell Deep Clean + Antibacterial formula. You’ll make 3 wet passes, forward, back, then forward again before making your dry passes. If the noise of the machine changes to a higher pitch during cleaning, check the dirty water tank. It fills faster in Deep cleaning mode and may need to be emptied more often. [13] X Research source
