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NA51259 has been discontinued
Discontinued April 17, 2026
This product was discontinued by the manufacturer.
MANUALS (3)
This item replaces: NA51059
Direct Replacement:
3/4" Sweat Serviceable Flow Check Valve (Low Lead)
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Product Highlights
–
3/4"
C x C Connection
17 Cv
Brass
Description
–
3/4" Sweat Serviceable Flow Check Valve (Low Lead)
Product Description
A check valve ensures that water only flows in a single direction of a plumbing or hydronic system. The NA51 series low-lead serviceable inline spring check valves, ideal for residential and commercial applications, feature union connections with a variety of end connection options for easy installation and maintenance. The valve is constructed of a stainless steel body and low-lead brass or copper tailpieces
Product Features
Product Description
A check valve ensures that water only flows in a single direction of a plumbing or hydronic system. The NA51 series low-lead serviceable inline spring check valves, ideal for residential and commercial applications, feature union connections with a variety of end connection options for easy installation and maintenance. The valve is constructed of a stainless steel body and low-lead brass or copper tailpieces
Product Features
- Max percentage of glycol: 50%
- Max working pressure:150 psi
- Temp range: 32° - 150°F (190°F for max 1 hour)
- Opening pressure differential: 0.25 psi (1/2" through 1-1/4”); 0.50 psi (1-1/2”, 2")
Specs
–
| Size: | 3/4" |
|---|---|
| Connection Type: | C x C |
| Connection Method: | Sweat |
| Flow Capacity (Cv): | 17 |
| Material: | Brass |
Contact
+
Questions?
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Product Reviews
5 out of 3 reviews
100% would recommend this product
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Showing 1-3 of 3 reviews
Great check valve
Product fits and works exactly as advertised. Easy install and seals well.
Jake
Phoenix
3 years ago
Verified Buyer
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Check valve
So far so good...
kevin
Washington
4 years ago
Verified Buyer
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I would buy this product again.
I'm using this product just upstream on a mixing valve. It's been working great. These have good flow and are quite. You can use them in any position as long as your water flow is in the direction of the arrow. You can't go wrong with Caleffi. Everything they make is a work of art next to others.
Pat
Michigan
5 years ago
Verified Buyer
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