WATTS LF7 Series Dual Check Valves

Watts LF7 Series dual check valves stop the reverse flow of dirty water from entering the drinking water supply at individual outlets or the service entrance.

Filter
WATTS 3/8 LF7A
WATTS 3/4 LF7 U2-2B
WATTS 1 LF7 U2-2C
WATTS LF7-10-U2 1 1/4X1D
WATTS LF7 3/8E
WATTS LF7U2-2 1 1/4X1 1/4F
WATTS LF7-4-U2 1 1/4X1G
WATTS LF7U3-3 1 1/4 X 1 1/4H
WATTS LF7U4-3 1 1/4X1I
WATTS LF7C 3/8J
Backflow Preventer Type: Dual Check , Body Pattern: Inline , Body Style: Inline , Compliance: ASSE 1024 , Connection Type: FNPT , Inlet Thread Type: NPT , Mfr. Series: LF7 , Operation: Continuous , Valve Type: No Shutoff Valve
StyleModelMax. Working PressureBody MaterialDisc MaterialMin. Temp.Outlet ConnectionOutlet SizeOutlet TypeSeat MaterialPrice (inc. GST)
A
3/8 LF7		-------- SGD 338.07
B
3/4 LF7 U2-2		-------- SGD 165.86
C
1 LF7 U2-2		-------- SGD 180.77
D
LF7-10-U2 1 1/4X1		10.3 BarLead Free BronzeSantoprene33 Degree F-1"Female ThreadedBuna-N SGD 353.29
E
LF7 3/8		10.3 BarLead Free BrassSilicone33 Degree F-3/8"Female ThreadedBuna-N SGD 350.10
F
LF7U2-2 1 1/4X1 1/4		10.3 BarLead Free BronzeSantoprene33 Degree F-1-1/4"Female ThreadedBuna-N SGD 334.05
G
LF7-4-U2 1 1/4X1		10.3 BarLead Free BronzeSilicone33 Degree F-1"Union Female ThreadedBuna-N SGD 352.22
G
LF7-10-U3 1 1/4X1		10.3 BarLead Free BronzeSilicone33 Degree F-1"Union Male ThreadedBuna-N SGD 483.93
H
LF7U3-3 1 1/4 X 1 1/4		150 psiLead Free Copper Silicon AlloySilicone33° FMale Threaded1-1/4"Male ThreadedBuna N SGD 419.69
I
LF7U4-3 1 1/4X1		150 psiLead Free Copper Silicon AlloySilicone33° FMale Threaded1"Male ThreadedBuna N SGD 327.58
J
LF7C 3/8		150 psiLead Free Copper Silicon AlloySilicone33° FFemale Threaded3/8"Female ThreadedBuna N SGD 375.77

Working Mechanism

  • Pressure pushes the valve open, letting water flow through the pipes.
  • After the pump shuts off, the weight of the water pushes the valve closed.

Features

  • Watts LF7 Series dual check valves can be installed vertically or horizontally in piping applications with a broad range of copper setters, meter horns & boxes.
  • They feature lead-free cast copper silicon alloy construction for improved strength & minimised brittleness and have Buna-N seat material for abrasion resistance.
  • These FNPT-connection type units come equipped with two plastic check valves that are easily replaceable and a steel spring for hazard water system containment in continuous pressure applications.
  • They are available in a combination of outlet / inlet types, sizes, thread and end connections along with hose connections and retrofit compression fittings.

Standards and Approvals

  • ASSE 1024
  • UL
  • CSA
  • FM
  • NSF
  • ULC

Frequently Asked Questions

What is the maximum working pressure of these valves?

These valves operate under pressures ranging from 10 to 150 psi under temperatures up to 180 degrees F.

What are the benefits of double check valves?

  • The other check valve takes over if the first check valve becomes stuck open.
  • Closed check valves provide tighter seals and prevent even small leaks by lowering the pressure differential across the other valve.

What are the points to remember while installing these valves?

  • They should be installed downstream of the water meter & the water pressure regulator.
  • They should always be installed in an accessible location for easy servicing and testing.
  • Pipe lines should be thoroughly flushed to remove foreign material before installing the unit.
  • Protect from freezing and ensure that the valve is installed in the proper flow direction.
  • Refer to flow direction arrow on valve nameplate or body.
  • When installing a valve in the pipeline, only use wrenching flats.
  • These valves incorporate an O-ring union seal that requires minimum tightening of the union nut, therefore do not over tighten.
  • These valves contain plastic check modules and should never be directly soldered into the line.

We are here to help!

Looking for a part not listed here?

Chat with us now

Explore More