Product Description
Submersible Pump for Flat Roof Ponding and Residual Dewatering
Product Overview
The HCP GDR-400 is a lightweight submersible puddle sucker used for residual water removal on flat surfaces. It is commonly applied in flat roof drainage, basements, pools, and utility cleanup, where near-complete water removal is required. The pump uses a dry motor with water cooling and a urethane vortex impeller for low-level operation. HCP is Taiwan’s most successful submersible pump manufacturer.
Key Benefits of this Submersible Puddle Sucker
Removes water down to 1 mm on flat surfaces to eliminate standing water.
Removes residual water efficiently on flat surfaces using a low-level vortex suction design.
Resists wear in light sand and silt applications with a urethane rubber impeller and hydraulic components.
Prevents motor burnout using an integrated auto-cut thermal protector.
Ensures reliable operation with double mechanical seals (Silicon Carbide) in an oil-filled chamber.
Adapts to various setups with an exchangeable 50 mm (2") vertical or horizontal discharge.
Operates effectively as a portable puddle sucker for basements and confined spaces.
HCP GDR-400 Specifications
Category
Details
Model
GDR-400
HP / kW
1/2 HP / 0.4 kW
Voltage / Phase
115V / Single Phase (1Ø)
Frequency
60Hz
Discharge Size
2" (50 mm) Standard (Convertible to Vertical/Horizontal)
Max Flow Rate
64 GPM
Max Head
39 ft (11.8 m)
Solid Passage
0.25 in (6.35 mm)
Rated Current
5.8 A
Motor Type
2 Pole, Dry Motor, Water Cooling
Insulation Class
Class B
Protection Rating
IP68
Start Method
Capacitor
Impeller Type
Urethane Rubber Vortex
Mechanical Seal
Double Mechanical Seals (CA/CE & SiC/SiC)
Cable Length
32 ft (10m)
Weight
Approx. 26 lbs (11.8 kg)
Dimensions
7.3" (185mm) W x 12.0" (305mm) H
What’s Included
HCP GDR-400 2" Submersible Puddle Sucker Pump
32-ft Power Cable with Water-Resistant Cable Base
Convertible Discharge Outlet (Vertical/Horizontal)
Rubber Suction Pads (Base)
Key Features of HCP GDR-400
Residual Water Removal
The pump starts at a water level of 5 mm and continues pumping down to 1 mm, making it highly effective for final cleanup.
Vortex Impeller Pump Design
A rubberized vortex impeller creates a whirlpool effect, allowing small debris and residual solids to pass without direct contact, reducing clogging risks during residual dewatering.
Water Cooling Motor
The cooling design allows the motor to run efficiently even at low water levels, preventing overheating during prolonged use.
Durable Urethane Rubber Impeller Pump
The impeller and casing are made of synthetic and urethane rubber, offering high wear resistance for construction site dewatering.
Multi-Directional Discharge
The discharge port can be mounted vertically or horizontally, preventing hose kinking when used in shallow water or on uneven ground.
Epoxy Resin Sealed Cable Base
The cable entry is sealed with epoxy resin to prevent moisture ingress into the motor, extending the lifespan of the unit.
Performance Overview
The GDR-400 2" submersible puddle sucker pump delivers stable flow performance at low water levels and is optimized for residual dewatering on flat surfaces. It performs best in clear water applications where near-complete drainage is required, and operates reliably when kept properly submerged for cooling.
Applications
Flat roof drainage and ponding removal
Basement and utility room cleanup
Swimming pool and pond draining
Construction site dewatering
General residue dewatering for tanks
Emergency flood water removal
Civil engineering and groundworks
Common Use
High efficiency puddle sucker for pools
Lightweight construction site dewatering pump
Submersible pump for flat roof ponding
1/2 HP residual water pump
Installation & Use Notes
Surface Requirement: Best used on flat surfaces to achieve the 1 mm water level removal capability.
Start Level: Requires a minimum water depth of 5 mm (0.2") to prime and start pumping.
Discharge Orientation: Use the horizontal discharge position for shallow water to avoid hose kinks; use vertical for pits.
Operating Limits: Do not let the pump run dry for extended periods. Ensure the liquid temperature remains between 0–40°C (32–104°F).
Check Valve: When pumping vertically, a check valve is recommended to prevent backflow when the pump stops.
Control: This is a manual pump. For automatic operation, an external control switch is required.
Accessories & Add-Ons
Automatic Control: Add an Alderon Surfacemax Utility Pump Piggyback Control Switch to automate the on/off cycles based on water presence.
Discharge Hoses: Pair with a Brown PVC Layflat Hose Assembly for reliable water transport.
Quick Connections: Use a Type A Aluminum Camlock for fast and secure hose attachment to the pump's discharge.
Your Professional-Grade Pumping Solution
Cleanflow supplies the HCP GDR-400 to contractors and facility managers who require reliable submersible dewatering pumps for critical drainage tasks.
As a supplier of the HCP pump line, we ensure you receive equipment supported by technical expertise and robust availability across North America.
Frequently Asked Questions
How low can the HCP GDR-400 pump water down to?
The HCP GDR-400 can remove water down to approximately 1 mm (0.04 inches) on a flat surface, making it ideal for residual dewatering and flat roof ponding applications.
Does the HCP GDR-400 turn on automatically?
No, the standard GDR-400 is a manual pump. Automatic operation requires an external control switch such as a piggyback utility control switch.
What is the minimum water level required to start the GDR-400?
The pump requires a minimum water depth of approximately 5 mm (0.2 inches) to prime and begin operation.
Can I use a layflat hose with the HCP GDR-400?
Yes. The GDR-400 features a 2-inch (50 mm) discharge port and supports layflat hose connections. The discharge can be configured horizontally to reduce hose kinking in shallow water applications.
Is the impeller durable enough for construction site use?
Yes. The pump uses a urethane rubber vortex impeller designed to resist wear from light sand and silt commonly found on construction sites.
What is the discharge size of the HCP GDR-400?
The pump includes a 2-inch (50 mm) discharge port that can be configured for either vertical or horizontal orientation.
Can the HCP GDR-400 handle solids?
The GDR-400 is designed primarily for residual clear water removal but can pass small solids up to 0.25 inches (6 mm) in diameter.
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