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Saniflo 21 Residential Water Pump, Grey,1/3 HP Reviews

4.6 Rating 125 Reviews
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The Saniflo MPN 21 residential water pump transforms basement remodeling projects by eliminating traditional drainage limitations through its specialized 1/3 HP motor configuration. This grey-colored thermoplastic housing unit measures exactly 8.75 inches in height, 9 inches in width, and 10.25 inches in depth, positioning itself as the compact solution for residential drainage challenges where gravity flow proves impossible.  Weighing 13 pounds, this Saniflo pump delivers 18 gallons per minute discharge capacity at its maximum 14-foot vertical lift specification, making it the definitive choice for basement apartments, laundry installations, and remote kitchen additions where conventional drain systems cannot reach the main sewer line. Unlike standard sump pump configurations designed for groundwater removal, the MPN 21 features three strategically positioned 1.5-inch inlets—two low-profile side inlets with integrated check valve protection and one top-mounted inlet—enabling simultaneous wastewater collection from multiple fixtures without requiring complex manifold assemblies.  The unit's 120-volt, 60-hertz electrical specification draws a maximum 4.5 amperes during operation, qualifying it for standard residential circuit integration while maintaining CSA certification under both IPC and NSPC plumbing code standards. Precision-Engineered Oil-Filled Motor Technology Delivering Maintenance-Free Performance The permanently sealed oil-bath motor assembly within the Saniflo 021 eliminates traditional maintenance intervals found in conventional drain pump applications. This 0.3 horsepower induction motor operates at precisely 3,600 revolutions per minute, driving a direct-coupled impeller through a single spindle shaft that minimizes mechanical complexity and potential failure points.  The oil-filled enclosure surrounding the motor provides continuous lubrication, thermal protection through efficient heat dissipation, and acoustic dampening that reduces operational noise to just 44 decibels measured at three feet—quieter than most residential dishwasher cycles and significantly below the threshold requiring hearing protection in occupied spaces. The thermoplastic housing material surrounding the motor assembly resists corrosion from prolonged wastewater exposure while maintaining structural integrity at operating temperatures up to 140 degrees Fahrenheit.  This temperature threshold accommodates hot water discharge from washing machines, dishwashers, and utility sinks without requiring cooling periods or thermal protection devices. The polyethylene construction also provides chemical resistance against common household cleaning agents, laundry detergents, and kitchen effluent containing mild acids or alkaline compounds. Engineering specifications reveal the motor's 30-microfarad capacitor rating ensures consistent starting torque under varied load conditions, preventing the motor stall issues that plague less sophisticated residential pump designs.  The pressure switch activation mechanism responds to water level changes within the 2.75-gallon capacity chamber, triggering motor engagement only when sufficient volume accumulates for efficient discharge cycles lasting between two and ten seconds depending on horizontal pipe run configurations and vertical lift requirements. Three-Inlet Configuration Maximizing Installation Versatility Across Residential Applications The Saniflo MPN 21's triple inlet design accommodates diverse fixture combinations without requiring additional collection pits or intermediate pumping stations. Both side-mounted 1.5-inch inlets incorporate factory-installed check valves that prevent backflow during system operation, eliminating the need for separate valve installation and reducing potential leak points in the drainage assembly.  These low-profile inlets position just above the unit's base, facilitating gravity drainage from floor-level shower bases constructed on minimum 6-inch elevated platforms using dimensional lumber framing techniques. The quarter-inch per foot slope requirement toward the pump ensures consistent flow without standing water accumulation in horizontal drainage runs. The top-mounted inlet provides alternative connection routing for fixtures positioned above the pump housing,

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“great product, packaging could heve been better”
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Posted 11 years ago
NewHopeBuyer
Verified Reviewer
“The plumber likes Saniflo devices and installed this one quickly and cleanly. He struggled a bit with the instructions and said they were not as clear as they could be. His company had a pump for about $100 more so I saved money and got good value. It is interesting that the Saniflo company does not want installers to run long horizontally, but demands a short horizontal run in the instruction booklet, almost immediately to a vertical one. Since the old failed pump vented into the sink, the plumber did the same with the Sanivite.I did have one part missing. A previous Saniflo Saniswift had many parts missing, requiring a return to plumbingsupplyandmore. The Saniswift was small and would have done the job, but the price to upgrade to the Sanivite was not too much and I hoped a more expensive pump would arrive with all it's parts. With just one small piece of the Sanivite missing, I was able to call the company and they mailed me the part within the week.The Sanivite services a utility sink and a bar sink quietly and efffectively.”
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Posted 11 years ago
“It works good. I was surprised I had my doubts.”
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Posted 11 years ago
“This is a great little pump. Arrived on time as usual. I was a little worried when I saw the size of pump but it had no problem keeping up with washer pumping into slop sink at full blast. Easy to install if your handy.”
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Posted 11 years ago
“Work Great! I use it for my backyard BBQ Island. Don’t use it much but so far everything is working as advertised.”
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Posted 11 years ago
“simply awesome!!!!”
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Posted 11 years ago
“Worked lie a charm”
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Posted 11 years ago
“Very best solution for a shower in places where bathroom or shower would be impossible, the pump.very quiet perfectly size . Easy to iinstall. perfect for basements. Love it.”
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Posted 11 years ago