Product Description
1/2 HP Cast Iron Sewage Ejector Pump for Heavy-Duty Residential and Commercial Wastewater Applications
This Hydromatic SK50 sewage pump efficiently manages heavy wastewater in homes and businesses. You can rely on this submersible cast-iron sewage pump for underground sewage basins and septic systems. The Hydromatic 1/2 HP sewage pump effectively moves water and waste to municipal sewer lines or drain fields.
Quick Specs
Horsepower: 1/2 HP
Voltage: 115V
Discharge Size: 2" NPT
Solids Handling: 2"
Cord Length: 20 ft
Max Head: 22 ft
Flow Rate: 80 GPM
Key Features of Hydromatic SK50A1 20 Sewage Ejector Pump
The two-vane semi-open cast iron impeller effortlessly passes spherical materials up to two inches in diameter.
Class 30 cast iron body construction delivers exceptional durability and long-lasting wear resistance for heavy-duty applications.
An oil-filled motor with upper and lower single-row ball bearings reduces friction and extends the operational lifespan.
Automatic thermal overload protection prevents overheating and automatically resets to keep your system operating safely.
The 20-foot wide-angle tethered float switch with a piggyback plug allows straightforward installation and simple manual operation testing.
Hydromatic SK50 Sewage Ejector Pump Specifications
Category
Details
Pump Type
Submersible Sewage Ejector Pump
Model Number
SK50A1 20 (Part # 516540127)
Horsepower
1/2 HP
Voltage
115V
Phase
1
Frequency
60 Hz
Amp Draw (Full Load)
12 Amps
Speed
1750 RPM
Maximum Capacity
80 GPM
Maximum Head
22 Feet
Maximum Liquid Temperature
130°F (55°C)
Agency Listing
CSA and cUL
Warranty
1 Year Limited
Performance Overview
The Hydromatic delivers a maximum capacity of 80 GPM and a maximum head of 22 feet, making it a highly capable commercial wastewater ejector pump.
Pump Performance – Head (ft) vs Flow Rate (GPM)
Flow Rate (GPM)
Head (ft)
0
24
20
22
40
19
60
16
80
14
100
12
110
9
Construction & Design
Category
Details
Body Construction
Class 30 Cast Iron
Impeller Type
Two Vane Semi-Open Cast Iron
Motor Type
Oil-Filled PSC with Thermal Overload
Shaft Seal
Carbon/Ceramic Type 21
Bearings
Upper and Lower Single Row Ball Bearings
Switch Type
Wide Angle Tethered Float (20-Ft Cable)
Discharge Size
2" NPT
Solids Handling
2" Spherical
Cord Type
20-Ft SJTW (16/3)
Applications
Residential sewage ejector systems
Commercial wastewater management
Septic tank effluent pumping
High-capacity sump pit drainage
Underground basement wastewater transfer
Heavy-duty 2-inch solid handling wastewater pump applications
Explore More Sewage Pump Solutions
Hydromatic Pumps Collection – View all Hydromatic brand pumps.
Sewage Pumps Collection – Explore more sewage pump models.
Sewage Pump Accessories – Find accessories and components.
Why Choose the Hydromatic SK50A1 20 Sewage Ejector Pump
Buy a Hydromatic SK50A1 20 sewage ejector pump when you need a dependable Hydromatic SK50 replacement sewage pump 120V or 115V system. This robust 2-inch solid handling sewage pump provides reliable automatic operation for years of use.
Available through Cleanflow, a trusted Hydromatic pumps supplier across Canada and the USA.
Frequently Asked Questions
What size solids can this pump handle?
It can handle solids up to 2 inches in diameter.
Can I use this for high-temperature liquids?
The maximum liquid temperature is 130°F (55°C).
How does the piggyback float switch work?
It allows automatic operation based on water levels and manual testing when needed.
Is this a suitable direct replacement pump?
Yes, it can replace identical models including Myers MSK50A1 20.
What pipe size do I need for installation?
It requires a 2" NPT discharge connection.
Does this pump require a dedicated circuit?
Yes, it requires a properly grounded 115V outlet.
How do I maintain the pump if it sits idle?
Run the pump monthly to ensure proper operation.
Free shipping. Usually ships same or next day. 
