Milwaukee Valve 509Y 3/4" FNPT Bronze Swing Y Check Valve
A bronze swing Y check valve with 0.5 psi cracking pressure, 18 gpm flow and 200 psi water rating for horizontal or vertical mounting
- Size3/4 in
- Bronze body resists corrosion up to 425 °F
- Swing Y design allows horizontal or vertical mounting
- 5 psi cracking pressure opens with minimal flow
- Full-flow 18 gpm capacity at 200 psi water rating
- 125 psi steam rating suits heating systems
Bronze Y Swing Check Valve
The Milwaukee Valve 509Y is a bronze swing check valve with a Y-pattern body designed for 3/4 inch FNPT connections. It suits plumbing and hydronic systems that require automatic backflow prevention in horizontal or vertical orientations. The bronze body and seat resist corrosion in water and steam service up to 425 degrees Fahrenheit. Installers needing a compact, full-flow check valve for residential or light commercial piping will find it appropriate.
Pressure and temperature limits
The valve handles a maximum water pressure of 200 psi at 150 degrees Fahrenheit and a maximum steam pressure of 125 psi WSP. Operating range extends from minus 20 degrees Fahrenheit to 425 degrees Fahrenheit. A cracking pressure of .5 psi allows the disc to open with minimal head loss. Systems exceeding these pressure or temperature ratings must use a different valve design.
Flow capacity
Rated flow is 18 gallons per minute with full-flow porting that matches the pipe bore. This single figure determines whether the valve can meet the demand of the circuit without excessive pressure drop. Applications requiring higher flow rates need a larger valve size.
How it compares
Measured against everything we stock in Bath Accessories & Soap Dispensers, at today’s prices. Recalculated every night.
- Price $53.99
- Pricier than about 58% of the 1,499 comparable items (median $39.99).
Specifications
| Product | |
|---|---|
| Brand name | MILWAUKEE VALVE |
| Product type | Other |
| Size & build | |
| Size | 3/4 in |
Questions about this item
Which size and connection type should I select for a 3/4-inch FNPT piping system?
This valve is supplied in a single 3/4-inch FNPT x FNPT configuration, so it matches that pipe size and thread type directly.
How much water can pass through the valve in normal service?
The published flow rating is 18 gpm with full-flow design, indicating the capacity you can expect under typical pressure conditions.
What pressure limit does the FNPT connection impose at elevated temperature?
The valve is rated for 200 psi water pressure at 150 degrees F and 125 psi steam pressure, which are the practical caps for the FNPT ends.
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