Install Instructions

ManualsBrandsWatts ManualsBackflow Preventers3" LF709-OSY Lead Free Double Check Valve Assembly

Installation, Maintenance, & Repair

Series 709/LF709/709DCDA

Double Check Valve Assemblies

Double Check Detector Assemblies

Sizes:

⁄4" – 10" (20-250mm)

RP/IS-709/709DCDA

8" (200mm) 709 OS&Y shown

Testing

For field testing procedure, send for IS-TK-DL, IS-TK-7,

IS-TK-9A, IS-TK-99E AND IS-TK-99D.

For other repair kits and service parts, send for PL-RP-BPD.

For technical assistance, contact your local Watts

representative.

NOTE: For Australia and New Zealand, line strainers

should be installed between the upstream shutoff valve

and the inlet of the backflow preventer.

Its important that this device be tested periodically in com-

pliance with local codes, but at least once per year or

more as service conditions warrant. If installed on a fire

sprinkler system, all mechanical checks, such as alarm

checks and backflow preventers, should be flow tested

and inspected internally in accordance with NFPA 13 and

NFPA 25.

You are required to thoroughly read all installation instructions

and product safety information before beginning the installa-

tion of this product. FAILURE TO COMPLY WITH PROPER

INSTALLATION AND MAINTENANCE INSTRUCTIONS

COULD RESULT IN PRODUCT FAILURE WHICH CAN

CAUSE PROPERTY DAMAGE, PERSONAL INJURY AND/

OR DEATH. Watts is not responsible for damages resulting from

improper installation and/or maintenance.

Local building or plumbing codes may require modifications to the

information provided. You are required to consult the local build-

ing and plumbing codes prior to installation. If this information

is not consistent with local building or plumbing codes, the local

codes should be followed.

Need for Periodic Inspection/Maintenance: This product

must be tested periodically in compliance with local codes, but at

least once per year or more as service conditions warrant.

Replace internal components every 5 years.

Corrosive water conditions, and/or unauthorized adjustments or

repair could render the product ineffective for the service intended.

Regular checking and cleaning of the product’s internal compo-

nents helps assure maximum life and proper product function.

WARNING

Summary of content (8 pages)

PAGE 1
RP/IS-709/709DCDA Installation, Maintenance, & Repair Series 709/LF709/709DCDA Double Check Valve Assemblies Double Check Detector Assemblies Sizes: 3⁄4" – 10" (20-250mm) 8" (200mm) 709 OS&Y shown ! WAR NI NG You are required to thoroughly read all installation instructions and product safety information before beginning the installation of this product.
PAGE 2
Installation Instructions Series 709/LF709/709DCDA CAUTION: Do not install with strainer when backflow preventer is used on seldom-used water lines which are called upon during emergencies, such as fire sprinkler lines, etc. It is important that Series 709 and LF709 be tested periodically in compliance with local codes, but at least once a year or more often, depending upon system conditions. (Send for IS-TK-7).
PAGE 3
Installation Instructions (cont.) Series 709/LF709/709DCDA Outdoor Installations In area where freezing conditions do not occur, Series 709 and LF709 can be installed outside of a building. The most satisfactory installation is above ground and should be installed in this manner whenever possible. It is generally recommended that backflow preventers never be placed in pits unless absolutely necessary and then only when approved by local codes.
PAGE 4
Service, Replacement Parts and Maintenance Series 709/LF709/709DCDA / " – 2" (20-50mm) 3 4 1. After removing the cover screw, the check comes out with the cover. 2. Holding the check Valve module in both hands, rotate the assembly 1⁄4 turn. This will disengage the disc and spring assembly into individual components. The disc assembly may be cleaned or replaced. O-rings should be cleaned or replaced as necessary and lightly greased with the FDA approved silicon grease.
PAGE 5
Service, Replacement Parts and Maintenance Series 709/LF709/709DCDA Repair Kits 709/LF709 2 / " – 10" (65-250mm) 1 2 21⁄2" – 10" (65-250mm) 1. Remove hatch cover bolts. NOTE: The 709 and LF709 is designed so that, when the bolts are backed off 1⁄2", all the spring load is released from the cover and retained by the check module. CAUTION: Be sure to verify this before removing all the bolts.
PAGE 6
Service, Replacement Parts and Maintenance Series 709/LF709/709DCDA 3" – 10" (80-250mm) **WARNING: Spring assembly is factory assembled. DO NOT DISASSEMBLE. Cover Cover O-ring Repair Kits 709DCDA **Disc & Spring Assembly 3" – 10" (80-250mm) Ordering code Kit No. Size in.
PAGE 7
Troubleshooting Guide Series 709/LF709/709DCDA Symptom Cause Solution 1. Check valve fails to hold a. Debris on check disc Disassemble and clean 1.0 PSID minimum sealing surface b. Leaking gate valve Disassemble and clean or repair c. Damaged seat disc or seat o-ring Disassemble and replace d. Damaged guide holding check open Disassemble and clean or replace Disassemble and replace spring e. Weak or broken spring 2. Chatter during flow a.
PAGE 8
Limited Warranty: Watts Regulator Co. (the “Company”) warrants each product to be free from defects in material and workmanship under normal usage for a period of one year from the date of original shipment. In the event of such defects within the warranty period, the Company will, at its option, replace or recondition the product without charge. THE WARRANTY SET FORTH HEREIN IS GIVEN EXPRESSLY AND IS THE ONLY WARRANTY GIVEN BY THE COMPANY WITH RESPECT TO THE PRODUCT.