DeWalt 20V MAX Transfer Pump

I picked up the DeWalt transfer pump to solve a recurring annoyance: moving water where outlets are scarce or dragging an extension cord is more trouble than the job itself. After several weeks of using it for garden watering, draining appliances, and as a backup around a sump pit, I have a pretty clear picture of where this cordless pump shines—and where you’ll want to reach for something else.

Setup and ergonomics

The pump is compact and light enough to carry one-handed, and it sits stable on the floor or a step without walking around once it’s running. The housing feels solid, the hose connections are straightforward, and the LED-embedded power switch is easy to see and use in dim mechanical rooms. It’s self-priming, which removes a lot of frustration; in practice, I still try to keep the inlet line as short as practical and minimize high spots to help it prime quickly.

The pump uses standard garden-hose style connections, so you can be up and running with hoses you likely already own. I added brass quick-connects to speed up changes between suction and discharge setups. There’s a slot for a TOOL CONNECT tag if you manage a fleet; most homeowners won’t care, but facilities teams will appreciate that touch.

Battery and charger are sold separately. I ran it mostly on a 5Ah 20V MAX pack, with some tests on a 6Ah pack. The tool-only approach keeps the upfront weight down and plays nicely if you’re already on DeWalt’s platform.

Performance and flow

DeWalt rates the pump at up to 10 gallons per minute with tap water, with a typical flow around 4.5 GPM against significant head. Real-world numbers vary with hose diameter, hose length, elevation change, and restrictions like wands or filters. With a 5/8-inch garden hose on both sides and roughly 75 feet total hose length, I saw around 6–8 GPM when moving water at ground level into open discharge (timed a 5-gallon bucket). Add elevation and flow drops, as expected. Pushing from a rain barrel up to a raised bed and through a watering wand, I still got a satisfying spray—not a pressure washer blast, but plenty for irrigation.

Suction performance is better than I expected for a cordless unit. On a short inlet with a stainless strainer, it primed quickly and didn’t cavitate unless I introduced kinks or ran the inlet too high above the source. DeWalt lists up to 25 feet of lift and a typical flow around 4.5 GPM with about 45 feet of head on tap water. In day-to-day use, that translates to: if you’re lifting from a basement floor drain up a story to discharge outside, it will still move water at a useful pace.

As with any transfer pump, keep an eye on fittings and avoid restrictions on the inlet side. A larger-diameter, smoother hose on the suction side helps, and a simple strainer prevents debris from stalling the impeller.

Runtime

Runtime depends on how hard you’re pushing it. On a fresh 5Ah pack (DCB205), I consistently moved in the ballpark of 250–300 gallons per charge with tap water—roughly in line with DeWalt’s claims. That’s enough to empty a typical water heater, relocate a tote, or irrigate garden beds from a rain barrel multiple times before swapping batteries. With a 6Ah pack, I comfortably stretched through several shorter tasks in a day without recharging.

The pump doesn’t like running dry, so I avoid letting the source run out while I’m distracted. When the stream sputters, I flip the switch off rather than let it freewheel; it restarts fine once you re-submerge the inlet.

Fluids and use cases

This pump is purpose-built for water and water/propylene glycol mixes up to 60% water and 40% glycol. That makes it handy for HVAC winterization tasks—circulating antifreeze through small loops—without lugging a corded unit. It’s not for fuels, solvents, or dirty graywater loaded with solids. I’ve run clean rainwater, tap water, and a mild glycol mix through it; I flushed with clean water afterward and had no issues.

Where it’s particularly useful:
- Garden and landscape irrigation from rain barrels or totes, especially when the water source is far from power.
- Draining water heaters or appliances when you don’t want a corded pump snaking across finished spaces.
- Moving water between tanks, aquariums, or totes without wrestling with siphons.
- Providing a quick assist around a sump pit during heavy rain if you need to redirect water elsewhere. I’ve used it to reduce the water level while troubleshooting a primary pump—fast and controlled.

Noise and heat

Noise-wise, it’s audible but not obnoxious—more of a whirring motor and water rush than a high-pitched whine. In long runs, the housing gets warm but never alarmingly hot in my use. I give it short breaks between big transfers mostly out of habit; for continuous duty on a large job, a corded utility pump still makes more sense.

Durability and maintenance

Fit and finish are on par with other DeWalt 20V tools. The switch feels positive, the battery connection is solid, and the pump body hasn’t scuffed badly despite being parked on concrete and turf. Self-priming mechanisms can be sensitive to grit; a simple inlet strainer is cheap insurance. After running a glycol mix, I always flush with clean water. There’s no complex maintenance schedule—just keep it clean, don’t run it dry, and store it drained.

DeWalt backs it with a 1-year limited warranty, extendable to 3 years when registered. For a tool like this—used intermittently but critically—that coverage is reassuring.

Practical tips from use

• Use the biggest, shortest, and smoothest suction hose you can. Kinks and narrow passages on the inlet side hurt priming and flow more than restrictions on the discharge side.
• Elevate or stabilize the pump so the inlet points straight, and keep the suction line below the pump body to help it prime faster.
• Add quick-connects to both sides to reduce setup time. A ball valve on the discharge can help you control flow without deadheading.
• If you’re winterizing with glycol, label a dedicated hose and fittings, and flush the pump afterward.
• If you’re pulling from a tank or barrel, a weighted strainer keeps the inlet submerged and reduces air ingestion as the level drops.

What it’s not

This isn’t a trash pump. It won’t tolerate sand, leaves, or heavy particulates. It’s not a pressure pump for sprinklers or deep wells, and it won’t replace a dedicated sump pump for unattended use. Also note: it’s intended for tap water and water/propylene glycol mixtures; check the manufacturer’s guidance before using it for potable applications or anything outside that scope.

If you need to move thousands of gallons continuously or handle dirty water, a larger corded utility or trash pump is the right tool. If you need pressure for irrigation zones, look at dedicated booster pumps.

Value

As a tool-only purchase, the price lands above bargain corded transfer pumps but below professional cart-mounted rigs. If you already own DeWalt batteries, the value improves significantly. The time saved by going cordless—no cords across wet ground, no hunting for outlets—adds up fast for maintenance techs, plumbers, and homeowners who do seasonal chores.

Pros and cons

Pros:
- Cordless convenience with flow that rivals small corded transfer pumps
- Self-priming and easy to use; LED switch is a thoughtful touch
- Moves up to roughly 300 gallons per 5Ah charge in real-world tasks
- Compatible with water and water/propylene glycol mixes up to 40% glycol
- Compact, stable, and fleet-friendly with TOOL CONNECT tag slot

Cons:
- Not for dirty water or fuels; requires clean sources and a strainer
- Battery sold separately, and runtime depends on head and hose setup
- Not a replacement for continuous-duty or high-pressure applications

Recommendation

I recommend the DeWalt transfer pump for anyone who needs a portable, no-cord solution to move clean water: homeowners with rain barrels, maintenance crews draining appliances, plumbers and HVAC techs circulating water or glycol in small systems, and anyone who wants a reliable backup to redirect water in a pinch. It’s fast to deploy, delivers honest flow, and runs long enough on a 5Ah battery to complete typical transfer tasks. If your work involves heavy solids, high pressure, or continuous unattended operation, pick a different style of pump. For everything else in the clean-water transfer category, this one earns a spot on the truck.