Watts Series 709 User manual

Series
709/709DCDA
Double Check Valve Assemblies
Double Check Detector
Assemblies
Sizes: 3⁄4" – 10" (20-250mm)
RP/IS-709/709DCDA
Watts 8" (200mm) 709 OS&Y shown
• Installation • Service
• Repair Kits • Maintenance
For field testing procedure, send for IS-TK-DP/DL,
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 repre-
sentative on back page.
IMPORTANT: Inquire with governing authorities for local
installation requirements.
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
compliance 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 preven-
ters, should be flow tested and inspected internally
in accordance with NFPA 13 and NFPA 25.
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2
Watts Series 709 Double Check Valve
may be installed in either a vertical or hori-
zontal position.
Install valve in the line with arrow on valve
body pointing in the direction of ow.
They should always be installed in an
accessible location to facilitate testing
and servicing.
Pipe lines should be thoroughly ushed to
remove foreign material before installing
the unit. A strainer should be installed as
shown, ahead of backow preventers to
prevent discs from unnecessary fouling.
CAUTION: Do not install with strainer
when backow preventer is used on sel-
dom-used water lines which are called
upon during emergencies, such as re
sprinkler lines, etc.
It is important that Series 709 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).
Indoor Installations
For indoor installations, it is important that
the valve be easily accessible to facilitate
testing and servicing.
Outdoor Installations
In area where freezing conditions do not
occur, Series 709 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 backow
preventers never be placed in pits unless
absolutely necessary and then only when
approved by local codes. In such cases,
a modied pit installation is preferred
or an insulated above ground insulated
enclosure.
Vertical Horizontal
Watts 709S
21⁄2" – 10"
Strainer
Indoor Installations
▼
▼
mm A mm
21⁄2" – 3" 65-80 10" 300
4 100 15" 450
6 150 15" 450
8 200 23" 680
10 250 25" 750
Clearance Required
for Servicing
A
Now Available,
WattsBox Insulated
Enclosures.
For more information, send for ES-WB
or ES-WB-T.
Above Ground in Insulated Enclosure
For indoor installations, it is important that the valve be
easily accessible to facilitate testing and servicing.
Outdoor Installations
Meter
Strainer
Watts 709S
21⁄2" – 10" (65-250mm)
Basic Installation Instructions
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3
Parallel Installations
Two or more Series 709 devices may be piped
in parallel (where approved) to serve a large
supply pipe main. This type of installation
is employed whenever it is vital to maintain
a continuous supply of water where inter-
ruptions for testing and servicing would be
unacceptable. It also has the advantage of
providing increased capacity where needed
beyond that provided by a single valve.
For two valve installations the total capacity
of the devices should equal or exceed that
required by the system. Capacity table shows
the size of the No. 709 devices required to
meet a certain capacity. The quantity of
devices used in parallel should be deter-
mined by the engineer's judgement based
on the operating conditions of a specic
installation.
Watts 709S
21⁄2" - 10"
The following Test Procedure is one of several that is recognized
throughout the United States for verication of the functioning of
Backow preventers.
The following procedure is not a specic recommendation. The Watts
series of test kits are capable of performing any of the recognized
Backow test procedures.
A. Flush all test cocks
B. Turn tester on (before connecting hoses). Tester must read
all zeroes. Close VA and VB.
Test No. 1 - Test No. 1 Check Valve
1. Install high side hose between testcock No. 2 and
tester connection A.
2. Install low side hose between testcock No. 3 and
tester connection B.
3. Open testcock No. 2 then VA, bleed hose then close VA.
4. Open testcock No. 3 then VB, bleed hose then close VB.
5. Install a bypass hose between VB and testcock No. 1.
Open testcock No. 1 and bleed by loosening hose
connection at VB. Tighten hose connection, fully open VB.
Push - Print Head (wait) then Push - Start Test
6. Close shutoff valve No. 2 then No. 1.
7. Slowly open VA and lower high side pressure about
-2 psid below the low side pressure (differential read
ing about -2.0 psid). Close VA. If reading is maintained,
record as “tight”. If reading returns to 0 and the
pressure A increases to pressure B, the check is
recorded as leaking. If the reading returns to +psid,
No. 2 shutoff valve is leaking excessively and must be
replaced to test the valve.
8. Close all test cocks, remove hoses from testcock No. 2
and testcock No. 3 and testcock No. 1. Reopen
shutoff valve No. 1. Proceed to Test No. 2.
Push - Stop Test.
Test No. 2 - Test No. 2 Check Valve
1. Install high side hose between testcock No. 3 and
tester connection A.
2. Install low side hose between testcock No. 4 and tester
connection B.
3. Open testcock No. 3 then VA, bleed hose then close VA.
4. Open testcock No. 4 then VB, bleed hose then close VB.
5. Install a bypass hose between VB and testcock No. 1.
Open testcock No. 1 and bleed by loosening hose
connection at VB. Tighten hose connection, fully open VB.
Push - Start Test
7. Close shutoff valve No. 1.
8. Slowly open VA and lower high side pressure about
-2 psid below the low side pressure (differential read
ing about -2.0 psid). Close VA. If reading is maintained,
record as “tight”. If reading returns to 0 and the
pressure A increases to pressure B, the check is
recorded as leaking. If the reading returns to +psid,
No. 2 shutoff valve is leaking excessively, and must be
replaced to test the valve.
Push - Stop Test.
VA ABVB
TK-DP
Test Kit
Capacity Required for System
450 GPM 640GPM 1000GPM 2000GPM 3000GPM 5000GPM
Two 21⁄2" Two 3" Two 4" Two 6" Two 8" Two 10"
Devices Devices Devices Devices Devices Devices
Table shows total capacity provided with dual valve installations of various sizes.
Basic Installation Instructions (cont.)
Test Procedure for Double Check Valve Assemblies
using Watts TK-DP and TK-DL Test Kit
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4
709 3/4" – 2"
EDP No. Kit No. Size
First or Second Check Kits in. mm
0887150 RK 709 CK4 3⁄4– 1 20-25
0887151 RK 709 CK4 11⁄2– 2 32-50
0887154 RK 709 CK4SS* 3⁄4– 1 20-25
0887155 RK 709 CK4SS* 11⁄2– 2 32-50
Kit includes: Disc assembly, Spring, Seat, Seat o-ring and Cover O-ring.
Complete Rubber Parts
0887152 RK 709 RT 3⁄4– 1 20-25
0887153 RK 709 RT 11⁄2– 2 32-50
Kit includes: Diaphragm, Disc assembly, Seat o-ring and Cover o-ring.
Seat Kits
0887160 RK 709 S4 3⁄4– 1 20-25
0887161 RK 709 S4 11⁄2– 2 32-50
0887162 RK 709 S4SS* 3⁄4– 1 20-25
0887163 RK 709 S4SS* 11⁄2– 2 32-50
Cover Kits
0887156 RK 709 C1 3⁄4– 1 20-25
0887157 RK 709 C1 11⁄2– 2 32-50
0887158 RK 709 C2 3⁄4– 1 20-25
0887159 RK 709 C2 11⁄2– 2 32-50
Kit includes: Cover and Cover o-ring.
*Stainless Steel
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
1⁄4turn. 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. Reassemble
the check valve module in the reverse order.
NOTE: The springs of the rst and second check valves
are interchangeable.
(Before servicing, be certain water is turned off or
shutoff valves are closed)
First Check Second Check
Cover
Cover
O-ring
Spring
Disc
Holder
Assembly
Seat
Seat
O-ring
Rubber Parts
Kit
First Check
Kit
Second Check
Kit
Rubber
Parts
Kit
Service, Replacement Parts and Maintenance 3/4" – 2" (20-50mm)
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5
1. Remove hatch cover bolts. NOTE: The 709 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.
2. Lift check valve module straight out, taking care not to hit and
damage seat ring.
3. The seat ring may be removed and replaced by pulling out the two
wire retainers. The wire retainers are 10" long. One is drawn out
clockwise and the other is drawn out counterclockwise.
4. With the retainer wires removed, the seat ring can be lifted straight
up and removed.
CAUTION: The check valve disc and spring assembly are in
compression. The spring load is captured by the two spring retainers
and the stem The spring retainers are not to be removed for servicing.
If there is a need to replace the spring, spring retainer or stem, replace
the disc and spring assembly. If the disc holder has been damaged
by freezing or severe water hammer, it can be replaced in the field.
Remove the disc holder retaining ring and slide the disc holder off the
stem. Remover the o-ring from the stem and replace with a new one.
Apply grease to the o-ring and slide the new disc holder into place. Re-
install the retaining ring. NOTE: The disc holder should not be removed
when servicing only the disc, remove allen head screws holding the
disc retaining plate and replace disc.
709 21⁄2" – 10" (65-250mm)
EDP No. Kit No. Size
First or Second Check Kits in mm
0887900 RK 709 CK4 21⁄2– 3 65-80
0887901 RK 709 CK4 4 100
0887902 RK 709 CK4 6 150
0887903 RK 709 CK4 8 200
0887904 RK 709 CK4 10 300
Kit includes: Disc & spring assembly and Cover O-ring.
Rubber Parts (for one check)
0887905 RK 709 RC4 21⁄2– 3 65-80
0887906 RK 709 RC4 4 100
0887907 RK 709 RC4 6 150
0887908 RK 709 RC4 8 200
0887909 RK 709 RC4 10 250
Kit includes: Disc and Cover O-ring.
Complete Rubber Parts
0887915 RK 709 RT 21⁄2– 3 65-80
0887916 RK 709 RT 4 100
0887917 RK 709 RT 6 150
0887918 RK 709 RT 8 200
0887919 RK 709 RT 10 250
Kit includes: Two discs and Two Cover O-rings.
Seat Kits
0887910 RK 709S 21⁄2– 3 65-80
0887911 RK 709S 4 100
0887912 RK 709S 6 150
0887913 RK 709S 8 200
0887914 RK 709S 10 250
Kit includes: Seat, Seat o-ring, Retainer Wire and Cover O-ring.
Cover Kits
0887920 RK 709 C 21⁄2– 3 65-80
0887921 RK 709 C 4 100
0887922 RK 709 C 6 150
0887923 RK 709 C 8 200
0887924 RK 709 C 10 250
Kit includes: Cover and Cover O-ring.
709DCDA 3" – 10" (80-250mm)
EDP No. Kit. No. Size
First Check Kits in mm
0887930 RK 709DCDA CK1 3 80
0887931 RK 709DCDA CK1 4 100
0887932 RK 709DCDA CK1 6 150
0887933 RK 709DCDA CK1 8 200
0887934 RK 709DCDA CK1 10 250
Second Check Kits
0887935 RK 709DCDA CK2 3 80
0887936 RK 709DCDA CK2 4 100
0887937 RK 709DCDA CK2 6 150
0887938 RK 709DCDA CK2 8 200
0887939 RK 709DCDA CK2 10 250
Kit includes: Disc assembly, Spring assembly and Cover O-ring.
Rubber Parts (for one check)
0887940 RK 709DCDA RC4 3 80
0887941 RK 709DCDA RC4 4 100
0887942 RK 709DCDA RC4 6 150
0887943 RK 709DCDA RC4 8 200
0887944 RK 709DCDA RC4 10 250
Kit includes: Disc and Cover O-ring.
Seat Kits
0887945 RK 709DCDA S 3 80
0887946 RK 709DCDA S 4 100
0887947 RK 709DCDA S 6 150
0887948 RK 709DCDA S 8 200
0887949 RK 709DCDA S 10 250
Kit includes: Seat, Retainer Wire and Cover O-ring.
Cover Kits
0887950 RK 709DCDA C 3 80
0887951 RK 709DCDA C 4 100
0887952 RK 709DCDA C 6 150
0887953 RK 709DCDA C 8 200
0887954 RK 709DCDA C 10 250
Kit includes: Cover and Cover O-ring.
Spring Retainer
(Do Not Remove)
Spring
O-ring
Spring Retainer
(Do Not Remove)
Disc
Disc Holder
Retaining Ring
Disc Retainer Allen Head
Socket Screws
Stem
Disc Holder
*Warning: Spring assembly
is factory assembled. DO NOT
DISASSEMBLE.
21⁄2", 3" (65-80mm)
4" - 10" (100-250mm)
Cover
Cover
O-ring
*Disc &
Spring
Assembly
Seat
Seat
O-ring
Retainer Wire
Seat
Second
Check
First
Check
Cover
O-ring
O-ring
Service, Replacement Parts and Maintenance 21/2" – 10" (65-250mm)
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6
Type & Purpose
REDUCED PRESSURE ZONE
BACKFLOW PREVENTER
For High Hazard Cross-connections and
continuous pressure application.
REDUCED PRESSURE DETECTOR ASSEMBLY
High Hazard
DOUBLE CHECK VALVE ASSEMBLY
For Low Hazard Cross-connections and
continuous pressure applications.
DOUBLE CHECK DETECTOR ASSEMBLY
Low Hazard
DUAL CHECK VALVE
BACKFLOW PREVENTER
For low hazard cross-connections.
Continuous pressure applications.
SPECIALTY BACKFLOW PREVENTERS with
INTERMEDIATE ATMOSPHERIC VENT
For low hazard cross-connections in small
pipe sizes. Continuous pressure applications
LABORATORY FAUCET DUAL CHECK VALVE
with INTERMEDIATE VACUUM BREAKER
In small pipe sizes for low hazard
ATMOSPHERIC VACUUM BREAKERS
For high hazard cross-connections not
subject to continuous pressure
- 6" above flood rim.
PRESSURE VACUUM BREAKERS
For high hazard cross-connections.
Continuous pressure applications -12" above
flood rim.
ANTI-SIPHON, ANTI-SPILL
VACUUM BREAKER
1" above flood rim Factory installed
6" above flood rim Field installed
HOSE CONNECTION VACUUM BREAKERS
For residential and industrial hose supply outlets
not subject to continuous pressure
Description
Two independent check
valves with intermediate
relief valve. Supplied
with shutoff valves and
ball type test cocks
RPZ valve backflow
preventers with a
water meter and RPZ in
bypass line.
Two independent check
valves. Checks are
replaceable for
repair & testing.
Double check valve
backflow preventers with a
water meter and double
check in by pass line.
Two independent check
valves. Checks are
replaceable for
repair & testing.
Two independent check
valves with intermediate
vacuum breaker and
relief vent.
Two independent check
valves with intermediate
vacuum breaker and
relief vent.
Single float and disc
with large atmospheric port
Spring loaded single float
and disc with independent
1st check. Supplied with shutoff
valves and ball type
test cocks.
Anti-spill vacuum breaker with
modular check & float assembly
of thermo plastic Housing
bronze body
Single check with
atmospheric vacuum
breakers vent.
Installed At
All cross-connections subject to
backpressure or back siphonage
where there is a high potential
health contamination.
Continuous pressure.
Fire protection system supply
main. Detects leaks and
unauthorized use of water.
All cross-connections subject to
backpressure or back siphonage
where there is a low potential
health contamination.
Continuous pressure.
Fire protection system supply main.
Detects leaks an unauthorized use
of water.
Cross-connections where there
is a low potential health hazard
and moderate
flow requirements
Cross-connections subject to
backpressure or backsiphonage
where there is low health hazard.
Continuous pressure.
Pressure outlet to prevent
backflow of carbon dioxide gas
and carbonated water into the
water supply system to
beverage machines
Cross-connections subject to
backpressure or backsiphonage
where there is low health hazard.
Cross-connection not subject to
backpressure or continuous
pressure. Install at least 6" above
fixture rim. Protection against
backsiphonage only.
Valve is designed for installation
in a continuous pressure potable
water supply system 12" above
the overflow level of the system
being supplied. Protection
against backsiphonage only.
Indoor point of use
Install directly on hose bibbs,
service sinks and wall hydrants.
Not for continuous pressure.
Examples of
Installations
Main supply lines
Commercial boilers
Hospital equipment
Laboratory equipment
Waste digesters
Car washes
Fire Sprinkler Lines
Main supply lines
Food cookers
Tanks & Vats
Lawn Sprinklers
Fire Sprinkler Lines
Commercial Pools
Fire Sprinkler Lines
Residential Supply Lines
(at the meter)
Residential fire sprinkler systems
Boilers (small)
Cooling towers (small)
Dairy equipment
Post-Mix Carbonated
Beverage Machine
Laboratory Faucets and
Pipe Lines
Barber shop and
Beauty Parlor sinks
Process Tanks
Dishwashers
Soap Dispensers
Washing Machines
Lawn Sprinklers
Laboratory equipment
Cooling towers
Commercial Laundry Machines
Swimming Pools
Chemical Planting tanks
Lawn Sprinklers
Chemical Dispenser
Commercial Dishwasher
Sterilizers
Hose bibbs
Service sinks
Hydrants
1
2
3
4
For additional cross-connection control information, send for F-50 brochure.
For Basic Types of Backflow Preventers
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7
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 Disassemble and replace
seat o-ring
d. Damaged guide holding Disassemble clean or replace
check open
e. Weak or broken spring Disassemble and replace spring
2. Chatter during flow a. Worn, damaged or Disassemble and repair or
conditions defective guide replace guide
3. Low flows passing a. Mainline check fouled Disassemble and clean
through mainline
valve (709DCDA only)
b. Meter strainer plugged Disassemble and clean
c. Damaged mainline seat Disassemble and replace
disc or seat
d. Broken mainline spring Disassemble and replace
Troubleshooting Guide
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For additional information, visit our web site at: www.watts.com
RP-IS-709_709DCDA 0829 EDP# 0835235 © Watts, 2008
USA: 815 Chestnut St., No. Andover, MA 01845-6098; www.watts.com
Canada: 5435 North Service Rd., Burlington, ONT. L7L 5H7; www.wattscanada.ca
Backflow Prevention Products
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. THE COMPANY MAKES NO OTHER
WARRANTIES, EXPRESS OR IMPLIED. THE COMPANY HEREBY SPECIFICALLY DISCLAIMS ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
The remedy described in the first paragraph of this warranty shall constitute the sole and exclusive remedy for breach of warranty, and the Company shall not be responsible for any incidental, special
or consequential damages, including without limitation, lost profits or the cost of repairing or replacing other property which is damaged if this product does not work properly, other costs resulting
from labor charges, delays, vandalism, negligence, fouling caused by foreign material, damage from adverse water conditions, chemical, or any other circumstances over which the Company has no
control. This warranty shall be invalidated by any abuse, misuse, misapplication, improper installation or improper maintenance or alteration of the product.
Some States do not allow limitations on how long an implied warranty lasts, and some States do not allow the exclusion or limitation of incidental or consequential damages. Therefore the above
limitations may not apply to you. This Limited Warranty gives you specific legal rights, and you may have other rights that vary from State to State. You should consult applicable state laws to
determine your rights. SO FAR AS IS CONSISTENT WITH APPLICABLE STATE LAW, ANY IMPLIED WARRANTIES THAT MAY NOT BE DISCLAIMED, INCLUDING THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE LIMITED IN DURATION TO ONE YEAR FROM THE DATE OF ORIGINAL SHIPMENT.
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