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Quick answer from a licensed plumber: For service calls, the DeWalt DCV581H: it runs on a 20V MAX battery or a cord, and DeWalt says its 2-gallon tank holds enough to empty a toilet or a clogged pipe. For a compact corded vac with a float shutoff, the RIDGID 4000RV. For pulling water out of drains and traps, the stainless Shop-Vac 5989305, the only one here with a sealed-pressure figure in the maker documents we read. For a flooded floor, the 16-gallon Craftsman with a built-in drain. For a lot of water, RIDGID and Shop-Vac say to take the filter out, but DeWalt says never to run the DCV581H without its filter. Stop when the float shuts off suction.
Our pick for most plumbers: the DeWalt DCV581H 20V MAX cordless/corded wet-dry vacuum. Check the DeWalt DCV581H on Amazon
A wet/dry shop vac does three plumbing jobs: it cleans up water, it pulls clogs and dropped objects back out of drains and toilets, and it empties a bowl, a trap or a tank before you open it up. This page compares four, from a cordless 2-gallon vac to a 16-gallon drum with a drain, all sold by Amazon.com when we checked. Specs come from the makers’ pages and manuals; where a maker page would not load, we say so and attribute the figure to the Amazon listing.
Shop Vacs Compared
| Vac | Power | Tank (maker) | Hose (maker or listing) | Drain or float (maker) | Notable |
|---|---|---|---|---|---|
| DeWalt DCV581H | 20V MAX battery or cord | 2 gal | 5 ft x 1-1/4 in. | Automatic shutoff | Enough to empty a toilet, per DeWalt |
| RIDGID 4000RV | Corded | 4 gal | 8 ft x 1-7/8 in. (listing) | Float | 20 ft cord (listing) |
| Shop-Vac 5989305 | Corded, 9.9 A | 5 gal, stainless | 7 ft x 1.25 in. | Float | 58 in. sealed pressure |
| Craftsman CMXEVBE17595 | Corded | 16 gal | 2-1/2 in. Dual-Flex | Oversized drain | Flood cleanup, per Craftsman |
Figures from DeWalt’s DCV581H page and manual, RIDGID’s 4000RV owner’s manual and the linked Amazon listing, Shop-Vac’s 5989305 page and manual, and Craftsman’s CMXEVBE17595 page. Tank sizes are drum volume; Craftsman notes that is not the same as how much a vac collects. Each linked vac was sold by Amazon.com and in stock on October 5, 2026.
What Plumbers Use a Shop Vac For
- Emptying a toilet or a sink. Pull the water out of the bowl before you pull the toilet, or out of a stopped sink before you open the trap. DeWalt says the DCV581H’s 2-gallon tank holds enough to empty a toilet or a clogged pipe.
- Pulling clogs and objects. A toy in a toilet or a hair plug in a tub drain often comes back out with suction; see our guide to an object flushed down a toilet.
- Water cleanup. A burst supply line or a leaking water heater. For a flooded floor, a big drum with a drain saves trips; for standing water deeper than you can vacuum, a submersible utility pump moves it faster.
- Draining. Pulling sediment-laden water from a water heater drain valve, or the last water from a line you cut into.
How to Vacuum Water Without Wrecking the Vac
The DeWalt, RIDGID and Shop-Vac manuals all cover wet pickup, and they differ on the filter. RIDGID says to remove the filter when there will be more than 2 inches of liquid in the drum, and Shop-Vac says to remove the cartridge for large amounts and use a foam sleeve when the liquid carries debris. DeWalt is the exception: its manual says the DCV581H needs no changes between wet and dry, and never to operate it without a filter in place. We have no Craftsman manual on file, so follow the one in the box. Watch for the float: when the tank is full, airflow stops and the motor pitch rises, per RIDGID and Shop-Vac, and DeWalt says the motor sound changes and suction drops. Turn it off and empty it then. Dry or rinse the filter afterward; RIDGID says to dry its filter after picking up liquid to avoid mildew.
Plumber’s note: if what you vacuumed was sewage, rinse the tank and wash or replace the filter before the vac goes back in the van, and keep it off a clean customer’s floor until you do.
DeWalt DCV581H 20V MAX Cordless/Corded Wet-Dry Vacuum
20V MAX battery or 120V AC cord (battery and charger sold separately) · 2-gallon tank · 5 ft x 1-1/4 in. hose · washable wet/dry HEPA filter · crevice tool and wide nozzle · blower port · 11.1 lb, 17.25 x 12.31 x 12.93 in. (DeWalt spec list) · 3-year limited warranty
This is the vac I would point a plumber to for service calls. DeWalt says its 2-gallon tank holds enough to empty a toilet or a clogged pipe, which is exactly the job: pulling the water out of a bowl before you set a new wax ring, or out of a sink that will not drain before you open the trap. It runs on a DeWalt 20V MAX battery or plugs into a wall outlet, and the manual says it switches between the two on its own. The cord does not charge the battery.
The manual says it works wet or dry with no parts to change, says never to operate it without a filter in place, and recommends emptying any dry debris before you pick up water. When the tank is full, the motor sound changes and suction drops; the vac must stay upright, or its automatic shutoff can trip. The included HEPA wet/dry filter rinses clean under running water, per DeWalt. The side exhaust port works as a blower, which the manual says can dry a damp floor. DeWalt’s manual describes it as a household-use vacuum.
- Battery or cord, per DeWalt
- 2-gallon tank holds enough to empty a toilet or a clogged pipe, per DeWalt
- Washable wet/dry HEPA filter
- Blower port to dry a damp floor
- 2 gallons: not for a flooded floor
- Battery and charger sold separately
- Narrow 1-1/4 in. hose
- DeWalt’s manual calls it a household-use vacuum
Verdict: The pick for plumbers on DeWalt 20V batteries who want a vac that rides along on every call.
RIDGID 4000RV 4-Gallon Portable Wet/Dry Vac
Corded · 4-gallon drum · float shutoff · Qwik Lock filter · Pro hose, car nozzle and muffler/diffuser included · blower · listing: 5.0 peak HP, 1-7/8 in. x 8 ft locking hose, 20 ft cord, 15 in. high, 14 lb
If you want more tank and a wider hose than a cordless vac, this compact RIDGID is a good second step. RIDGID’s manual covers the 4-gallon drum, a float that shuts off airflow when the water reaches a set level, and a Qwik Lock filter. The Amazon listing we link gives a 5.0 peak horsepower motor, a 1-7/8-inch by 8-foot locking hose, a 20-foot cord, a height of 15 inches and a weight of 14 pounds; RIDGID’s product pages did not load for us, so those figures come from the listing. The manual on file (printed 04/16) carries RIDGID’s full lifetime warranty against defects in workmanship and material; misuse, abuse and normal wear are not covered.
The manual is clear on wet pickup. With less than 2 inches of water in the drum, you can leave the filter in. With more, RIDGID recommends removing the filter, or it will saturate and you will see mist in the exhaust. When the float rises, airflow stops and the motor pitch goes up: turn it off, unplug it and empty the drum. Dry the filter afterward to avoid mildew. RIDGID’s manual says this vac is intended for household use.
- Float shuts off airflow when the drum is full, per RIDGID
- Wide 1-7/8 in. hose, per the listing
- 20 ft cord, per the listing
- Hose, nozzle and muffler included
- Corded only
- Spec figures come from the Amazon listing, not a RIDGID page
- RIDGID’s manual says it is for household use only
Verdict: The pick for a compact corded vac with a wide hose and a float shutoff.
Shop-Vac 5989305 5-Gallon 4.5 Peak HP Stainless Steel Wet/Dry Vacuum
Corded, 9.9 amps · 5-gallon stainless steel tank · 4.5 peak HP · 70 CFM max airflow · 58 in. sealed pressure · 160 peak air watts · 7 ft x 1.25 in. hose, 3 wands, 10 in. wet/dry nozzle, crevice tool, gulper nozzle · cartridge filter, foam sleeve and filter bag · 6 ft cord · limited lifetime home use warranty (original purchaser only, not transferable)
Of the maker documents we could read, only this one lists sealed pressure, and that number matters for plumbing. Shop-Vac defines sealed pressure as how far up a glass tube the motor will lift a column of water, and lists 58 inches for this model, with 70 CFM of maximum airflow. High lift is what pulls water up out of a drain or a toilet trap. The tank is stainless steel, which Shop-Vac calls durable and easy to clean.
Shop-Vac includes a foam sleeve as well as a cartridge filter. Its manual says to remove the cartridge for large amounts of liquid, and to use a foam sleeve when the liquid carries debris. A float shuts off suction when the tank is full; the manual warns that running the motor after the float rises will cause extensive motor damage. The cord is only 6 feet, so plan on an extension cord, and keep the connection out of the water.
- Sealed pressure listed: 58 in., per Shop-Vac
- Stainless steel tank
- Foam sleeve for wet pickup included
- Three wands and a 10 in. wet/dry nozzle
- 6 ft cord
- Narrow 1.25 in. hose
- No tank drain listed
- Warranty covers home use, original purchaser only
Verdict: The pick for pulling water out of drains and traps, with a tank that rinses clean.
Craftsman CMXEVBE17595 16-Gallon 6.5 Peak HP Wet/Dry Vac
Corded · 16-gallon drum · 6.5 peak HP · built-in oversized drain · 2-1/2 in. Dual-Flex hose · car, utility and wet nozzles · rear blower port · 246 in. cord · 26.7 in. high, 26.0 lb (Craftsman spec list) · 3-year limited warranty
When a supply line lets go and the basement floor is under water, you want a big drum and a drain. Craftsman says this 16-gallon vac makes cleaning up large renovations, builds or floods an easy task, and it has a built-in oversized drain that Craftsman says quickly empties liquid from the tank. The 2-1/2-inch hose, the widest on this page, has Dual-Flex ends that Craftsman says resist kinks and crushing.
Craftsman lists a 6.5 peak horsepower motor, a rear blower port, on-board hose and accessory storage, and a 246-inch cord, which works out to 20.5 feet (our arithmetic). Its footnote says the gallon rating is drum volume, not how much it will actually collect. One caution: the “Includes” list on Craftsman’s page describes a 5-gallon vac with a 1-7/8-inch hose, which does not match the rest of the page, so check the box contents against the Amazon listing.
- 16-gallon drum for floods, per Craftsman
- Built-in oversized drain
- Widest hose here, 2-1/2 in.
- Wet nozzle included
- 26.0 lb and 26.7 in. high, per Craftsman: a van-and-basement vac
- Craftsman’s page has a mismatched includes list
- Too big to carry under a sink
Verdict: The pick for flooded floors and big water cleanup.
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I send an occasional note when a new guide goes up — repairs worth doing yourself, and the parts that actually last. No spam, no course funnel; written by a licensed Georgia plumber.
What About Milwaukee?
I use a Milwaukee M18 shop vac on my jobs. We do not link Milwaukee vacs, because the Amazon listings we found for M18 wet/dry vacs were from third-party sellers. If you are already on Milwaukee batteries, buy from a dealer you trust and read Milwaukee’s own specs.
Before You Buy
- Size the tank to the job. Two gallons empties a toilet; a flooded floor wants 16 gallons and a drain.
- Look at the hose. The hoses here run from 1-1/4 to 2-1/2 inches across, per the makers and the RIDGID listing.
- Check the cord. The Shop-Vac’s cord is 6 feet; the Craftsman’s is 246 inches. Plan for an outdoor-rated extension cord.
- Read the use rating. DeWalt’s and RIDGID’s manuals describe these vacs as household-use, and Shop-Vac’s says household and workshop use, so check the warranty terms if the vac works every day on jobs.
- Battery or cord. Cordless for crawl spaces and service calls; corded for long cleanups.
Safety: Water, Cords and What Not to Vacuum
The DeWalt, RIDGID and Shop-Vac manuals all warn against handling the plug or the vac with wet hands, and RIDGID and Shop-Vac say to keep the extension cord connection out of the liquid. RIDGID says to use only outdoor-rated extension cords, no smaller than 16 gauge, with 14 gauge for 25 to 50 feet and 12 gauge beyond that. Do not vacuum flammable or combustible liquids such as gasoline, or anything that is burning or smoking, such as hot ashes, per the DeWalt, RIDGID and Shop-Vac manuals. RIDGID says not to vacuum drywall dust with the standard filter, because fine dust can pass through it. Unplug the vac before you empty it or change the filter.
FAQ
Can a shop vac unclog a drain?
Often, if the clog is close to the opening. A wet/dry vac can pull a wad of hair, a toy or a plug of debris back out of a sink, tub or toilet. Seal the hose to the opening and plug the overflow. Shop-Vac’s sealed-pressure figure (58 inches for the 5989305) is the number that tells you how hard a vac can lift water. A clog far down the line still needs a snake.
Should I take the filter out to vacuum water?
It depends on the vac. RIDGID says to leave the filter in for less than 2 inches of liquid in the drum and remove it for more, or it will saturate and mist out the exhaust. Shop-Vac says to remove the cartridge filter for large amounts of liquid and use a foam sleeve when the liquid carries debris. DeWalt says its DCV581H needs no changes between wet and dry, and its manual says never to operate it without a filter in place. Check the manual for your vac.
Why did my shop vac stop sucking while vacuuming water?
The tank is full and the float has shut off suction. RIDGID and Shop-Vac both say the motor will rise in pitch when this happens. Turn the vac off, unplug it and empty the tank. Shop-Vac warns that running it after the float rises can badly damage the motor.
Can I drain a water heater with a shop vac?
You can pull water from a drain valve with one, but let the tank cool first: none of the maker documents we read lists a water temperature limit for these vacs. For a full drain, a hose to a floor drain or a transfer pump is faster.
What extension cord should I use with a wet/dry vac?
RIDGID’s manual says to use only outdoor-rated cords in good condition, nothing smaller than 16 gauge, 14 gauge for 25 to 50 feet and 12 gauge beyond 50 feet, and to keep the connection out of any liquid. Shop-Vac also says to keep the cord connection out of the liquid you are vacuuming.
Why Trust Plumbing Picks
Plumbing Picks is written by a licensed Georgia journeyman plumber. Every spec here comes from the maker documents linked below, or from the Amazon listings we link; nothing comes from hands-on testing. On October 5, 2026, every linked listing was in stock and sold by Amazon.com. If you buy through a link we may earn a commission at no extra cost to you. Nobody pays to be included here. More on who writes this and how we pick.
Sources
- DeWalt: DCV581H 20V MAX cordless/corded wet-dry vacuum (product page), DCV581H instruction manual (NA131128)
- RIDGID: 4000RV 4-gallon wet/dry vac owner’s manual (printed as model 4000RV0)
- Shop-Vac: 5989305 5-gallon 4.5 peak HP stainless steel wet/dry vacuum (product page), user manual linked from that page (series SS11, SS14, SS16)
- Craftsman: CMXEVBE17595 16-gallon 6.5 peak HP wet/dry vac (product page)
- Amazon listings for each linked vac (linked above)
Bottom Line
Carry the DeWalt DCV581H on service calls if you run DeWalt 20V batteries, and keep a big corded vac like the 16-gallon Craftsman in the van for floods. For water, follow your vac’s manual on the filter, watch for the float, keep the cord connection dry, and rinse the tank after dirty jobs.