Comac Floor Scrubber Quality Checklist: 7 Checks Before You Buy

If you're buying a commercial floor scrubber or floor sweeper in 2025, you've probably read a stack of spec sheets and a few "review" roundups. This is different. This is the checklist I actually run on machines before they're approved to ship — and you can run it before you approve a purchase.

Quick background: I'm a quality compliance manager at a commercial cleaning equipment manufacturer. I review every unit before it goes out — roughly 2,000 floor scrubbers, sweepers, and dust collectors a year. In Q1 2024, I rejected about 7% of first-run units for issues like bad welds, misaligned brush decks, and squeegee gaps that would have shown up in the first month of operation.

This is a 7-point checklist. The order matters, and you should plan a solid two hours for the full test — longer if you're also checking a ride-on machine. Bring a multimeter, a flashlight, a straight edge, and a graduated container. You'll need them.

1. Check the frame before you check the shiny parts

Body panels get all the attention at trade shows. I start underneath, at the frame. Pick one corner, work your way along the base plate, and look at the welds around the brush deck mount and the wheel brackets. You want uniform, smooth welds — no globs, no skip-welding, no gray patches that suggest a cold weld.

• Weld consistency at the brush deck mount and axle brackets
• Base plate thickness vs. what the spec sheet claims
• Cut edges or exposed raw metal that will start rusting in a damp environment

A skip weld on the brush deck mount will crack within a year on a machine that runs six hours a day. I've seen it. That's the kind of thing that turns a $15,000 machine into a $4,000 repair bill. If you're not confident judging welds, bring someone who is — a maintenance person or a welder can tell you in 30 seconds whether a frame will hold up. That's a cheap consultation compared with the cost of a cracked frame.

2. Run the brush deck under load, not just in the air

Most buyers lower the deck onto a clean floor and watch the brushes spin. That tells you almost nothing. Run the deck under load for two or three minutes, then lift it and examine the bristle wear pattern. Uneven wear across the width means the deck isn't parallel to the floor.

If you're looking at a Comac Dapper floor sweeper — or any compact sweeper with a side brush — check the side brush pressure specifically. The adjustment is usually a small screw mechanism, and it's easy to over-tighten to the point where the brush stalls. A practical check: slide a piece of card under the side brush. If it gets pulled in but the motor keeps turning, the pressure is close to right. If the machine stalls, back the screw off.

3. Test the squeegee and water recovery separately

A machine can look great on a wet floor and still leave a film of water behind. Run a straight edge along the squeegee blade and check for daylight between the blade and the floor at any point. The blade should sit evenly across its whole width. Then do the actual recovery test: wet a section of floor, do one pass, and confirm the recovery tank is collecting water — not pushing it around.

Set your watch for one minute and see how much water gets pulled into the recovery tank. Compare that with the machine's rated vacuum lift. In 2024, I found brand-new units with clogged vacuum filters; the operator thought the machine was cleaning when it was really redistributing dirty water. That was the most common cause of "doesn't dry the floor" complaints in our audit that quarter.

4. Test the battery pack, not the dashboard indicator

Dashboard battery meters are optimistic — well, not deliberately, but a resting voltage isn't a load voltage. Put a multimeter on the pack terminals, engage the brush deck, and watch the loaded voltage. A healthy pack holds steady. A weak one sags within a few seconds. Walk away for 15 minutes and check it again.

On the lithium-ion models that now come standard on many ultra compact floor scrubber units, charger matching matters just as much as the cells. Five years ago, the battery check was "are the lead-acid cells topped up." By 2025, it's about BMS behavior, charge profiles, and firmware. I'm not a battery chemist, so I can't speak to cell-level chemistry differences. What I can tell you from a quality perspective: if the charger is mismatched, no battery will last. Also check the battery enclosure seal. On a scrubber, water and chemicals are everywhere; a pack that isn't sealed against moisture will fail early, no matter how good the cells are.

5. Measure the water flow — don't trust the dial

The control panel says 3.5 liters per minute. The machine you're actually buying might deliver 2.0 — or, on rare occasion, 4.2 when the flow regulator isn't calibrated. I time the real output into a graduated container and compare it with the rated spec. If a machine claims to cover a certain area per day, a 20% flow shortfall is a 20% shortfall in coverage.

Listen to the pump while you're at it. A consistent hum is normal; a surging or clicking pump is a red flag. Then park the machine for 10 minutes and check for drips under the solution tank. A slow leak on a showroom floor becomes a soap trail across a warehouse (and, honestly, a warranty claim you'd rather avoid).

6. Open the control panel and look at the wiring harness

This takes about five minutes and tells you how much the factory cared about the stuff nobody sees. Look for grommets where wires pass through metal, connectors that click into place, and cable routing that keeps wires away from moving parts. A messy harness is the first sign of assembly shortcuts. It won't show up on day one. It shows up on day 200, in the middle of a shift, as a short that takes the whole machine down.

Honestly, I'm not sure why some compact machines still ship with unsealed connectors inside the control panel — the cost difference is a few cents. But it's the first thing I check on any machine that's going to live in a damp environment.

7. Check serviceability — the step most buyers skip

Every machine will need maintenance. That's not a knock on any brand; it's physics. Can you swap the squeegee blades without tools? How long does a brush change take? On a Dapper floor sweeper, can you reach the dust filter without pulling the hopper apart?

These are cost questions. Replacement parts, labor, and lead times all become part of your total cost of ownership. I track spare-part lead times in our quarterly audits. A six-week wait for a brush is effectively a six-week hole in your cleaning schedule, and nobody budgets for that.

Ask the dealer for the parts price list — not the brochure. If replacement squeegee blades cost more than you expected, you want to know that before you buy, not after. And if the warranty covers parts but not labor, factor that in — labor is usually the bigger cost.

I approved a replacement brush supplier last year and spent the next two weeks second-guessing whether the fiber density matched the sample. The brushes were fine. But I still checked every batch for a month afterward.

Final notes: what to do with this checklist

I've run this checklist on a Timberline floor scrubber, on our own Comac units, and on competitive sweepers. The order doesn't change. The fundamentals haven't changed either: a floor scrubber has to pick up water, a sweeper has to contain debris, and the machine has to survive the full shift. What has changed is how much of that now depends on electronics and battery management instead of simple hydraulics — so the checklist has to change with it.

The value of a pre-purchase inspection isn't the two hours it takes. It's the certainty, months later, that the machine is still running when your crew needs it. That certainty is worth more than the discount you'd get by skipping the test.

Two last things. First, don't buy on spec sheets alone. A spec sheet describes what the machine is supposed to be; an inspection confirms what it actually is. Second, remember the total cost: the lowest quoted price is rarely the lowest total cost once you add downtime, spare parts, and service visits.

Most ultra compact floor scrubber reviews will tell you about runtime and turning radius. That's useful, but it's not enough. Run the checklist. Check the details. And if a dealer hesitates when you ask to open the control panel, that's an answer in itself.