Water Check Valve for Pump Systems

This springless water check valve is designed to prevent water from flowing back toward the pump when the valve is installed lower than the outlet line.

It helps maintain proper pump priming by avoiding:

• backflow into the lower pump line,
• air bubbles inside the system,
• cavitation problems,
• loss of suction in lifting or transfer pumps.

The internal piston automatically moves according to the water flow direction:

• normal flow → valve opens,
• reverse flow → valve closes and seals the system.

This makes it ideal for:

• water lifting pumps,
• irrigation systems,
• aquarium systems,
• water transfer installations,
• drainage systems,
• marine and camper applications.

Assembly Instructions

Assembly is very simple and follows the included exploded diagram.

Important:

• Install a 28 mm O-Ring seal inside the inlet fitting.
• Use PTFE/Teflon tape on all threaded parts to ensure a proper watertight seal.
• Flow direction must be:
  FROM the smaller inlet → TO the larger outlet

Recommended Printing Material

For best durability, pressure resistance, and watertight performance, print using:

• ABS
  or
• ASA

These materials provide better:

• thermal resistance,
• water resistance,
• mechanical strength,
• long-term outdoor durability.

PLA or PETG are not recommended for long-term pressurized water use.

Recommended Print Settings

• Infill: 35–60%
• Recommended Layer Height: 0.16 mm
• Maximum Layer Height: 0.20 mm

A higher infill is recommended for better pressure resistance and thread strength.

BSP Connections

• Inlet: Ø 28 mm — BSP 1" (G1)
• Outlet: Ø 40 mm — BSP 1½" (G1 1/2)

Features

✔ Springless piston design
✔ Prevents water backflow
✔ Helps maintain pump priming
✔ Reduces cavitation and air bubbles
✔ Compact and easy to assemble
✔ Compatible with BSP threaded systems
✔ Designed for water applications only