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Forespar 903000 Marelon 1-1/2" Vented Loop Anti-Siphon Valve

Manufacturer

Forespar

Picture for manufacturer Forespar

Part Number

903000
18 reviews
03/11/2036 7:20 PM
Sale Price

$24.03

In Stock (5)

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Usually delivered within 2 days

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Product Details

The Forespar 903000 Marelon Vented Loop is a critical safety component for marine plumbing systems, designed to prevent dangerous back-siphoning that could lead to flooding or sinking. This 1-1/2" vented loop valve allows air to enter drain lines when needed, breaking the siphon effect that can cause water to flow backward into the vessel.

Key Features:

  • Constructed from glass-reinforced Marelon composite for superior corrosion resistance
  • 1-1/2" NPT thread size for standard marine plumbing connections
  • Prevents back-siphoning in sink, shower, and discharge systems
  • Must be installed above the waterline for proper operation
  • Non-metallic construction eliminates galvanic corrosion concerns
  • Durable marine-grade materials withstand harsh saltwater environments

Vented loops are essential for any through-hull discharge system including heads, sinks, and pumps. The valve automatically opens to admit air when negative pressure develops in the line, preventing seawater from being siphoned back into the boat. This Marelon construction offers significant advantages over traditional bronze fittings, including lighter weight, no corrosion, and excellent strength-to-weight ratio.

Products specifications

Compatibility

In-Line

Diameter

For 1-1/2" Line

Material

Marelon

Type

Vented Loop

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