Why is my floor still wet?! Trouble-shooting the scrubber vacuum system

We sometimes hear the anguished cry of “My floor’s wet!” from scrubber and sweeper/scrubber owners and operators. The equipment makes a pass but leaves a wet floor behind. It’s an eyesore. A hazard. An indication that the investment in floor cleaning equipment isn’t paying dividends!

Fortunately, the wet floor problem is usually due to one of a few, simple-to-fix problems with the machine’s vacuum system. This article will give you trouble-shooting steps to go through if a scrubber or sweeper/scrubber leaves you with wet floors.

How scrubbers work

Let’s start with a review of how an automatic floor scrubber works. There are lots of different scrubber makes and models, but the basic operating principles are the same.

• First, cleaning solution is mixed with water and applied to the floor to loosen dirt
• Then brushes apply pressure and rotation to further loosen dirt and direct it along with the clean liquids to the vacuum system
• Finally, a vacuum system extracts the water, dirt and cleaning solution, leaving a clean, dry floor. The vacuum system includes a squeegee assembly which directs the dirt, etc. to a vacuum tube that suctions this residue into a holding tank.

Troubleshooting the vacuum system

If your scrubber is leaving a wet floor behind, try these steps to identify and solve the problem.

1. Make sure your vacuum has power

On most machines, you can hear the vac motor cycle when the machine is turned on. Also, make sure the vac motor is running when the squeegee assembly is dropped.

2. Check the recovery tank’s ball float valve

This is an emergency shut-off valve meant to prevent the recovery tank from overflowing. The ball floats at the level of the liquid in the tank and eventually blocks the intake tube when the level gets too high.

The status of the valve should be checked when the vacuum is both on and off. Is a plastic ball blocking the intake? If the answer is yes because the recovery tank is full, empty the tank. If the intake is blocked because the ball is stuck, gently dislodge the ball from the tube opening.

3. Check that the recovery tank is well-sealed

The recovery tank needs to be sealed tightly to generate good suction. To check whether the tank is sealed adequately, simply try to open the lid while the motor is on. It should be somewhat difficult to open the recovery tank lid while the vacuum system is running.

4. Check the gasket on the recovery tank lid

Sometimes there is dirt on the gasket that interferes with the seal, or the gasket may be worn or torn. While the lid is open, inspect the recovery tank lid gasket. If the gasket is dirty, wipe it down. If the gasket is damaged, replace it.

5. Check suction at the vacuum hose connection to the squeegee assembly

If the suction is weak, you probably have a clog to clean out. The vacuum hose is clear so you may be able to see the obstruction.

You can use an air pump to send air through the hose to help push the clog out. (You’ll want to close your recovery tank lid because the clog will be pushed into the recovery tank.)

You can also unplug the hose at the top and use a garden hose to push the clog out through the bottom by forcing water through the vacuum hose. If you use this method, you’ll want to be over a floor drain.

6. Make sure the squeegee assembly creates a good seal

The squeegees are essential for leaving a dry floor since they create the seal the vacuum needs to pull water from the floor. Any gaps between the blade and the floor will leave wet streaks. You can adjust the pressure on the squeegees so the entire length of the blade maintains consistent contact with the floor

Damaged blades will also leave streaks. Clean the squeegee blade after each use to remove dirt particles that may interfere with the seal. Check the blade for rips, tears, or frayed edges. If you find wear, flip the blade to an unused edge or replace it.

If you need help with these steps or if you’ve tried everything and nothing’s worked, call us. We’re here to help.

Rely on Morrison

Our floor cleaning equipment professionals are happy to work with you to determine what’s best for your operation—from machines to cleaning procedures to preventive maintenance. We offer top quality floor cleaning equipment from leading OEMs, and our factory-trained service technicians offer ongoing support and fast, knowledgeable service and parts for your floor cleaning equipment.