Watts N45B - Manual

Series N45B
Water Pressure Reducing Valves*
Sizes: 1 1 ⁄
4
" – 2" (32 – 50mm)
Series N45B Water Pressure Reducing Valves are designed to reduce
incoming water pressure to a sensible level to protect plumbing system
components and reduce water consumption. This series is suitable for water
supply pressures up to 300psi (20.7 bar) and may be adjusted from 25 –
75psi (172 – 517 kPa). The standard setting is 50psi (345 kPa). All parts are
quickly and easily serviceable without removing the valve from the line. The
standard bypass feature permits the flow of water back through the valve
into the main when pressures, due to thermal expansion on the outlet side
of the valve, exceed the pressure in the main supply.
Features
• Double union inlet & outlet connections
• Integral stainless steel strainer
• Thermoplastic seat & cage
• Bronze body construction
• Serviceable in line
• Bypass feature controls thermal expansion pressure**
• Sealed spring cage on all models for accessible outdoor or pit installations
Models
N45B NPT threaded female inlet x NPT female outlet
N4 5BU NPT threaded union inlet x NPT female outlet
N4 5BU-S Solder union inlet x NPT female outlet
N45BDU Double Union – NPT threaded union female inlet
and outlet
N45BDU-S Double Union – Solder union inlet and outlet
Specifications
A Water Pressure Reducing Valve and strainer shall be installed on the
water service pipe near its entrance to the building where supply main
pressure exceeds 60psi (413 kPa) to reduce it to 50psi (345 kPa) or lower.
Provision shall be made to permit the bypass flow of water back through
the valve into the main when pressures, due to thermal expansion on the
outlet side of the valve, exceed the pressure in the main supply. Pressure
reducing valves with built-in bypass check valves and integral strainer will
be acceptable. Approved valves shall comply with ASSE 1003. Valve shall
be a Watts Regulator Company Series N45B.
* A water saving test program concluded that reducing the supply pressure from
80 – 50psi (551 – 345 kPa) resulted in a water savings of 30%.
** NOTE: The bypass feature will not prevent the pressure relief valve from opening
on the hot water supply system with pressure above 150psi (10.3 bar).
For Residential and Commercial Applications
ES-N45B-L
Series N45BDU – 2" (50mm) size shown
Integral Stainless
Steel Strainer
Thermoplastic Seat
Thermal Expansion
Bypass
Threaded or
solder ends
Reinforced
Diaphragm
Watts product specifications in U.S. customary units and metric are approximate and are provided for reference only. For precise measurements,
please contact Watts Technical Service. Watts reserves the right to change or modify product design, construction, specifications, or materials with-
out prior notice and without incurring any obligation to make such changes and modifications on Watts products previously or subsequently sold.
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