Watts 909RPDA User manual

Series 909/909RPDA
Reduced Pressure Zone Assemblies
Reduced Pressure Detector Assemblies
Sizes: 21⁄2" – 10" (65 – 250mm)
• Installation • Service
• Repair Kits • Maintenance
For field testing procedure, send for IS-TK-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 representa-
tive on back page.
RP/IS-909/909RPDA
Watts 909 OSY shown
Designed for inline servicing
IMPORTANT: Inquire with governing authorities for local installa-
tion 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 accor-
dance with NFPA 13 and NFPA 25.
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.

Figure 2
TYPICAL FLOW RATES
VALVE AS SIZED BY FLOOR DRAIN
SIZE DRAIN MANUFACTURERS SIZE
in. mm in. mm
21⁄2" 65 55 gpm 2 50
3" 80 112 gpm 3 65
4" 100 170 gpm 4 100
6", 8", 10" 150,200,250 350 gpm 5 125
Basic Installation Instructions
Series 909
Sizes: 21⁄2" – 10" (65 – 250mm) 909
High Capacity Relief Series:
Location and Installation Considerations
6. The relief valve module on 21⁄2" – 10" (65 – 250mm) 909 Series
assemblies may be turned to discharge to the opposite side. To
do so, unbolt the relief valve and turn the relief valve discharge
port to the opposite side. Mount the high pressure hose on the
opposite. This should be done by a licensed journeyman trades-
person, who is recognized by the authority having jurisdiction
and only when space is critical for testing or repair.
7. ASSEMBLY: If the backflow preventer is disassembled during
installation, it MUST be reassembled in its proper order. The
gate valve with the test cock is to be mounted on the inlet side
of the backflow preventer. The test cock must be on the inlet
side of the wedge. Please see above. Failure to reassemble cor-
rectly will result in possible water damage due to excessive dis-
charge from the relief port/vent and possible malfunction of
the backflow preventer.
8. Installation procedures must comply with all state and local
codes and must be completed by a licensed journeyman
tradesperson who is recognized by the authority having juris-
diction. Please see Page 3 for specific installation procedures.
9. Prior to installation, thoroughly flush all pipe lines to remove any
foreign matter.
10.START UP at Initial Installation and After Servicing: The down-
stream shutoff should be closed. Slowly open upstream shutoff
and allow the backflow preventer to fill slowly. Bleed air at each
test cock. When backflow preventer is filled, slowly open the
downstream shutoff and fill the water supply system. This is nec-
essary to avoid dislodging O-rings or causing damage to internal
components.
11.TEST: The 909 Series backflow preventer may be test-
ed by a certified tester at the time of installation in order to
ascertain that the assembly is in full working order and may be
relied upon to protect the safe drinking water as per applicable
standard.
Figure 1 Series 909 RELIEF VALVE DISCHARGE RATES
ZONE PRESSURE (PSIG)
FLOW RATE (GPM)
Installation Note:
The flange gasket bolts for the
gate valves should be retight-
ened during installation as the
bolts may have loosened due
to storage and shipping.
Relief Valve
First
Check
Second
Check
Second
Shutoff
Valve
Inlet
Shutoff
Valve
21⁄2" – 3" 909
4" – 10" 909
175
150
125
100
75
50
25
0
0 100 200 300 400 500 600 700 800 900
Watts No. 909
21⁄2" – 10" (65 – 250mm)
2
1. Backflow preventers must be installed in high-visibility locations in
order to allow for immediate notice of telltale discharge or other
malfunction. This location should also facilitate testing and servic-
ing, and protect against freezing and vandalism.
2. Installing a backflow preventer in a pit or vault is not recom-
mended. However, if this becomes necessary, Watts highly rec-
ommends that a licensed journeyman tradesperson, who is rec-
ognized by the authority having jurisdiction, be consulted to
ensure that all local codes and required safety provisions are
met. An air gap below the relief port must be maintained so as
to avoid flooding and submersion of the assembly, which may
lead to a cross connection. *Please refer to Figure No. 1 for fur-
ther information.
3. A strainer should be installed ahead of the backflow preventer to
protect all internal components from unnecessary fouling.
Caution: Do not install a strainer ahead of the backflow preventer
on seldom-used, emergency water lines (i.e. fire sprinkler lines).
The strainer mesh could potentially become clogged with debris
present in the water and cause water blockage during an emer-
gency.
4. Normal discharge and nuisance spitting are accommodated by
the use of a Watts air gap fitting and a fabricated indirect waste
line. Floor drains of the same size MUST be provided in case of
excessive discharge. *Please refer to Figure No. 1 and Figure No.
2 for further information.
5. When a 909 Series backflow preventer is installed for dead-end
service applications. (i.e. boiler feed lines, cooling tower makeup
or other equipment with periodic flow requirements), discharge
from the relief vent may occur due to water supply pressure fluc-
tuation during static no-flow conditions. A check valve may be
required ahead of the backflow preventer. *Please see
“Troubleshooting”, Page 7, prior to installation.

Basic Installation Instructions
Series 909
Sizes: 21⁄2" – 10" (65 – 250mm)
Installation
A. Series 909 should be installed in a horizontal and
upright position. This positions the relief valve below the
first check valve, enabling the zone to drain through the
relief valve outlet. The shutoff valve with the test cock is to
be mounted on the inlet side of the backflow preventer. The
test cock is on the inlet side of the shutoff valve.
B. The 909 should always be installed in an accessible location
to facilitate testing and servicing. Check the state and local
codes to insure that the backflow preventer is installed in
compliance, such as the proper height above the ground.
C. Water discharge from the relief valve should be vented in
accordance with code requirements. The relief valve should
never be solidly piped into a drainage ditch, sewer or sump.
The discharge should be funneled through a Watts air
gap fitting piped to a floor drain.
D. Watts recommends a strainer be installed ahead of Watts
909 Series assemblies to protect the discs from unnec-
essary fouling.
E. Backflow preventers should never be placed in pits unless
absolutely necessary and then only when and as approved
by local codes. Consult your local or state plumbing or
health inspector. Watts recommends installation indoors or
above ground in an insulated enclosure.
Start Up
F. The downstream shutoff should be closed. Open upstream
slowly, fill the valve and bleed the air through Test cock 2, 3
and 4. When valve is filled, open the downstream shutoff
slowly and fill the water supply system. This is necessary to
avoid water hammer or shock damage.
G. The installation of a Watts air gap with the drain line termi-
nating above a floor drain will handle any normal discharge
or nuisance spitting through the relief valve. However, floor
drain size may need to be designed to prevent water dam-
age caused by a catastrophic failure condition. Do not
reduce the size of the drain line from the air gap fitting.
H. Two or more smaller size valves can be piped in parallel
(when approved) to serve a larger supply pipe main. This
type of installation is employed where increased capacity is
needed beyond that provided by a single valve and permits
testing or servicing of an individual valve without shutting
down the complete line.
The number of assemblies used in parallel should be deter-
mined by the engineer's judgement based on the operating
conditions of a specific installation.
Indoors
Above Ground
Parallel
TABLE ONE - CAPACITY REQUIRED FOR SYSTEM
50 gpm 100 gpm 150 gpm 200 gpm 250 gpm 350 gpm 450 gpm 640 gpm 1000 gpm 2000 gpm 3000 gpm 5000 gpm
Two 3⁄4" Two 1" Two 11⁄4" Two 11⁄2" Two 11⁄2" Two 2" Two 21⁄2" Two 3" Two 4" Two 6" Two 8" Two 10"
Devices Devices Devices Devices Devices Devices Devices Devices Devices Devices Devices Devices
Table shows total capacity provided with dual valve installations of various sizes.
Now available, WattsBox Insulated Enclosures, for more information,
send for ES-WB.
Watts 909S
21⁄2" - 10"
(65 - 250mm)
Meter Strainer
Main
Air
Gap
12" (300mm)
Min. 12" (300mm)
Watts 909
21⁄2" – 10"
(65 – 250mm)
Strainer
Air Gap
3
support

Test Procedure for Reduced
Pressure Zone Backflow Preventers
The following Test Procedure is one of several that is recognized
throughout the United States for verification of the functioning of
backflow preventers.
The following procedure is not a specific recommendation. The
Watts series of test kits are capable of performing any of the recog-
nized backflow test procedures.
A. Open TC #4 and flush test cocks Nos. 1, 2, and 3 on BF
assembly, then close TC #4.
B. Turn tester on (before connecting hoses). Tester must read all
zeros. Close VA and VB.
Test No. 1 - Relief Valve
1. Install high side hose between TC #2 and tester connection A.
2. Install low side hose between TC #3 and tester connection B.
3. Open VB then TC #3. Now open VA then TC #2 slowly. Close
VA then VB.
4. Close #2 shutoff valve.
5. Observe the apparent first check valve differential pressure (A - B).
6. Install bypass hose between VA and VB. Open VB and bleed
air by loosening hose connection at VA. Tighten hose connec-
tion and close VB.
Push - Print Head (wait) then Push - Start Test
7. Open VA, then slowly open VB (no more than 1⁄4turn). When
relief valve drips, push the “hold” button for 2 seconds.
Record reading (must be 2 psid or more).
Push - Stop Test
8. Close VA and VB.
Test No. 2 - Test No. 2 Check Valve
9. Install bypass hose between VA and TC #4. Open VA, then
bleed air by loosening hose connection at TC #4. Tighten
hose connection.
Close VA.
Push - Start Test
10. Open VB to reestablish pressure within the “zone”. Close VB.
11. Open VA then TC #4. If relief valve does not drip, record sec-
ond check valve as “closed tight”.
Test No. 3 - Test No. 1 Check Valve
12. Open VB to reestablish first check valve differential pressure.
Close VB. Record pressure differential.
Stop Test (Push Stop Test twice)
13. Close test cocks and remove tester, return assembly to nor-
mal operating condition.
4
Replacement Water Meters for 21⁄2" - 10" Series 909RPDA, 990RPDA and 992RPDA.
ORDERING VALVE
CODE SERIES SIZE DESCRIPTION
0835561 909RPDA/990RPDA/992RPDA 21⁄2" – 10" D709BA203-GPM-B (registers in gallons)
1203010 909RPDA/990RPDA/992RPDA 21⁄2" – 10" D709BB203-CFM-B (registers in cubic feet)
CFM AND GPM Outside Reader Kit
0899022 909RPDA/990RPDA/992RPDA 21⁄2" – 10" ROM DC/RP CFM-B
0899023 909RPDA/990RPDA/992RPDA 21⁄2" – 10" ROM DC/RP GPM-B
For complete testing information, send for IS-TK-9A or IS-TK-DP/DL.
Watts TK-DP
Water
Meter
Outside
Reader
RPZ
Test 1
RPZ
Test 2
RPZ
Test 3
VA ABVB
VA BVB
A
VA BVB
A

Servicing First and Second Checks
Sizes: 21⁄2" – 10" (65-250mm)
1. Remove the hatch cover bolts. NOTE: The 909 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 the check valve module straight out taking care not to hit and
damage the seating.
3. The seat ring may be removed and replaced by pulling out the
two wire retainers on sizes 4" – 10" (100 – 250) while on sizes
21⁄2" – 3" (65 – 80mm), one quarter turn twist removes seat.
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.
5. CAUTION: The check valve spring is 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, an assembled
module must be obtained from the factory. These modules are
not interchangeable, be sure to replace the first check with a first
check module and the second check with a second check module.
6. To replace the disc on sizes 21⁄2" – 4" (65 – 100mm) simply
remove the retaining nut or for sizes 6" – 10" (150 – 250mm)
remove the allen head socket screws. Reverse this procedure to
install the new disc.
909 Repair Kits 21⁄2" – 10" (65 – 250mm)
ORDERING CODE KIT NO. SIZE
First Check Kits: in. mm
0887210 RK 909 CK1 21⁄2– 3 65-80
0887212 RK 909 CK1 4 100
0887213 RK 909 CK1 6 150
0887214 RK 909 CK1 8 200
0887215 RK 909 CK1 10 250
Second Check Kits:
0887211 RK 909 CK2 21⁄2– 3 65-80
0887216 RK 909 CK2 4 100
0887217 RK 909 CK2 6 150
0887218 RK 909 CK2 8 200
0887219 RK 909 CK2 10 250
Kits include: Disc & Spring assembly, Cover O-ring and lubricant.
First Check Rubber Parts Kits:
0887220 RK 909 RC1 21⁄2– 3 65-80
0887221 RK 909 RC1 4 100
0887223 RK 909 RC1 6 150
0887224 RK 909 RC1 8 200
0887225 RK 909 RC1 10 250
Second Check Rubber Parts Kits:
0887226 RK 909 RC2 21⁄2– 3 65-80
0887227 RK 909 RC2 4 100
0887228 RK 909 RC2 6 150
0887229 RK 909 RC2 8 200
0887230 RK 909 RC2 10 250
Kits include: Lower Stem O-ring (6" only), Check disc, Cover O-ring, and lubricant.
Seat Kits for Checks:
0887730 RK 909 S 21⁄2– 3 65-80
0887731 RK 909 S 4 100
0887732 RK 909 S 6 150
0887733 RK 909 S 8 200
0887734 RK 909 S 10 250
Kits include: Seat, Seat O-ring, Cover O-ring, Retainer wire and lubricant.
Total Rubber Parts Kits:
0887750 RK 909 RT 21⁄2– 3 65-80
0887751 RK 909 RT 4 100
0887752 RK 909 RT 6 150
0887753 RK 909 RT 8 200
0887754 RK 909 RT 10 250
0887761 RK 909M1 RT 8 200
0887762 RK 909M1 RT 10 250
Kits include: Lower Stem O-ring (6" only), Check disc, Cover O-ring, Sleeve O-ring,
Piston O-ring, RV disc assembly, Diaphragm, Piston seal and Lubricant.
When ordering specify EDP number, Kit Number and Valve Size.
909RPDA Repair Kits 21⁄2" – 10" (65 – 250mm)
ORDERING CODE KIT NO. SIZE
First Check Kits: in. mm
0887239 RK 909RPDA CK1 21⁄2– 3 65-80
0887240 RK 909RPDA CK1 4 100
0887241 RK 909RPDA CK1 6 150
0887242 RK 909RPDA CK1 8 200
0887243 RK 909RPDA CK1 10 250
Second Check Kits:
0887244 RK 909RPDA CK2 21⁄2– 3 65-80
0887245 RK 909RPDA CK2 4 100
0887246 RK 909RPDA CK2 6 150
0887247 RK 909RPDA CK2 8 200
0887248 RK 909RPDA CK2 10 250
Kits include: Disc & Spring assembly, Cover O-ring and lubricant.
First Check Rubber Parts Kits:
0887249 RK 909RPDA RC1 21⁄2– 3 65-80
0887250 RK 909RPDA RC1 4 100
0887251 RK 909RPDA RC1 6 150
0887252 RK 909RPDA RC1 8 200
0887253 RK 909RPDA RC1 10 250
Second Check Rubber Parts Kits:
0887254 RK 909RPDA RC2 21⁄2– 3 65-80
0887255 RK 909RPDA RC2 4 100
0887256 RK 909RPDA RC2 6 150
0887257 RK 909RPDA RC2 8 200
0887258 RK 909RPDA RC2 10 250
Kits include: Lower Stem O-ring (6" only), Check disc, Cover O-ring, and lubricant.
Seat Kits for Checks:
0887735 RK 909RPDA S 21⁄2– 3 65-80
0887736 RK 909RPDA S 4 100
0887737 RK 909RPDA S 6 150
0887738 RK 909RPDA S 8 200
0887739 RK 909RPDA S 10 250
Kits include: Seat, Seat O-ring, Cover O-ring, Retainer wire and lubricant.
Total Rubber Parts Kits:
0887756 RK 909RPDA RT 21⁄2– 3 65-80
0887757 RK 909RPDA RT 4 100
0887758 RK 909RPDA RT 6 150
0887759 RK 909RPDA RT 8 200
0887760 RK 909RPDA RT 10 250
0887764 RK 909RPDAM1 RT 8 200
0887765 RK 909RPDAM1 RT 10 250
Kits include: Lower Stem O-ring (6" only), Check disc, Cover O-ring, Sleeve O-ring,
Piston O-ring, RV disc assembly, Diaphragm, Piston seal and Lubricant.
NOTE:
No special tools
required to service
Series 909
First and second checks
are not interchangeable
First
Check
Second
Check
Relief
Valve
*Warning: Spring assembly is factory assembled. DO NOT DISASSEMBLE
*Disc & Spring
Assembly
Seat
Seat O-ring
Cover O-ring
21⁄2" – 3"
(65 – 80mm) *Disc & Spring
Assembly
Retainer wire
Seat O-ring
Cover O-ring
4" – 10" (100 – 250mm)
Lower Stem
O-ring (6" only)
Seat
Disc
For further details contact your technical sales representative, see back page.
909OSY
5

Servicing the Relief Valve
Sizes: 21⁄2" – 10" (65-250mm)
1. Remove the relief valve cover bolts. Note the 909 is designed so
that when the bolts are backed off 1⁄2" all the relief valve spring
load is retained by the bottom plug spring module.
CAUTION: Be sure to verify this before removing all the bolts.
2. Remove the cover and diaphragm. The relief valve piston assem-
bly can be lifted straight up and out.
3. Replace the wiper seal and piston O-ring and apply grease to the O-ring.
4. To replace the relief valve disc, hold the upper guide fin and
unscrew the diaphragm pressure plate. It may be necessary to
lightly tap the cast webs and the pressure plate to loosen.
Replace with a new disc holder assembly and O-ring. Note: the
disc rubber is molded into the disc holder and is supplied as a
disc holder assembly.
5. Removal of the bottom plug and spring assembly. During normal
field service there is no need to remove the bottom plug spring
assembly other than inspection. It can be removed by simply
unscrewing with a large pipe wrench.
CAUTION: The spring as retained on the bottom plug is highly
loaded. NO attempt should be made in the field to remove the
spring. For replacement, a complete bottom plug assembly must be
obtained from the factory.
For further details contact your technical sales representative, see
back page.
909 Repair Kits 21⁄2" – 10" (65 – 250mm)
ORDERING CODE KIT NO. SIZE
Relief Valve Rubber Parts in. mm
0887231 RK 909 RV 21⁄2– 3 65-80
0887232 RK 909 RV 4 – 6 100-150
0887233 RK 909 RV 8 – 10 200-250
0887234 *RK 909M1 RV 4 – 10 100-250
Kits include: Sleeve o-ring, Seat o-ring, Piston o-ring, Stem o-ring, RV disc assembly,
Diaphragm, Piston seal, Bottom plug o-ring and lubricant
Relief Valve Total
0887235 RK 909 VT 21⁄2– 3 65-80
0887236 RK 909 VT 4 – 6 100-150
0887237 RK 909 VT 8 – 10 200-250
0887238 *RK 909M1 VT 4 – 10 100-250
Kits include: Adapter o-ring, Diaphragm, Disc & piston assembly, Seat, Seat
o-ring and lubricant. (4" – 10" M1 includes bottom plug & spring assembly.)
Cover Kits
0887740 RK 909 C 21⁄2– 3 65-80
0887741 RK 909 C 4 100
0887742 RK 909 C 6 150
0887743 RK 909 C 8 200
0887744 RK 909 C 10 250
Kits include: Cover, Cover o-ring and lubricant.
909RPDA Repair Kits 21⁄2" – 10" (65 – 250mm)
Relief Valve Rubber Parts
0887263 RK 909RPDA RV 21⁄2– 3 65-80
0887264 RK 909RPDA RV 4 – 6 100-150
0887265 RK 909RPDA RV 8 – 10 200-250
0887266 *RK 909RPDAM1 RV 4 – 10 100-250
Kits include: Sleeve o-ring, Seat o-ring, Piston o-ring, Stem o-ring, RV disc assembly,
Diaphragm, Piston seal, Bottom plug o-ring and lubricant
Relief Valve Total
0887259 RK 909RPDA VT 21⁄2– 3 65-80
0887260 RK 909RPDA VT 4 – 6 100-150
0887261 RK 909RPDA VT 8 – 10 200-250
0887262 *RK 909RPDAM1 VT 4 – 10 100-250
Kits include: Adapter o-ring, Diaphragm, Disc & piston assembly, Seat, Seat o-ring and
lubricant. (4" – 10"M1 includes bottom plug & spring assembly.)
Cover Kits
0887745 RK 909RPDA C 21⁄2– 3 65-80
0887746 RK 909RPDA C 4 100
0887747 RK 909RPDA C 6 150
0887748 RK 909RPDA C 8 200
0887749 RK 909RPDA C 10 250
Kits include: Cover, Cover o-ring and lubricant.
*M1 = Cast iron relief valve.
Clearance Required for Servicing
in. mm A B
21⁄2– 3 65-80 10" 11"
4 100 15" 14"
6 150 15" 16"
8 200 23" 21"
10 250 25" 21"
Relief Module
B
Adapter O-ring
Diaphragm Diaphragm
Relief Valve
Disc
Relief Valve Piston
Assembly
Piston O-Ring
Seat
O-ring
Sizes
21⁄2" – 3"
(65 – 80mm)
Sizes 4", 6"
(100, 150mm)
8"M1, 10"M1
Relief Valve Piston
Assembly
Piston seal
Seat
O-ring
Plug &
Spring
Piston
Assembly
Diaphragm
Sizes 8", 10"
(200, 250mm)
Relief Valve Assembly
Seat
O-ring
Plug & Spring
Assembly
6
Adapter o-ring

Troubleshooting Guide - Backflow Preventers
Problem Cause Solution
A. Valve spits periodically from the vent
A.1 Fluctuating supply pressure. A.1 Install a soft seated check valve immediately
upstream of the device.
A.2 Fluctuating downstream pressure A.2 Install a soft seated check valve downstream of
the device close as possible to the shutoff valve.
B. Valve drips continually from the vent
B.1 Fouled first check B.1 Flush valve. If flushing does not resolve problem,
disassemble valve and clean or replace the first
check.
B.2 Damage or fouled relief valve seat. B.2 Clean or replace the relief valve seat.
B.3 Relief valve piston O-ring not free to B.3 Clean, grease or replace the piston O-ring.
move due to pipe scale, dirt or build
up of mineral deposits.
B.4 Excessive back pressure, freezing, or B.4 Eliminate source of excessive backpressure or
water hammer has distorted the water hammer in the system downstream of the
second check. device. Use Watts No. 15 to eliminate water ham-
mer. Replace defective second check assembly.
In case of freezing; thaw, disassemble and inspect
internal components.
Replace as necessary.
B.5 Electrolysis or relief valve seat or first B.5 Replace relief valve seat or inlet cover.
check seats. Electrically ground the piping system and/
or electrically isolate the device with plastic pipe
immediately upstream and downstream of
the device.
B.6 Valve improperly reassembled. B.6 If valve is disassembled during installation,
caution must be exercised to install check springs
in their proper location.
C. Valve exhibits high pressure drop.
C.1 Fouled strainer. C.1 Clean strainer element or replace.
C.2 Valve too small for flows encountered. C.2 Install proper size device based upon
flow requirements.
D. No water flows downstream of valve.
D. Valve installed backwards. D. Install valve in accordance with flow
direction arrow.
E. Valve does not test properly
E.1 Follow manufacturer's test procedure E.1, E.2 Clean or replace gate valve with full port ball
valves or resilient wedge shutoff valves.
E.2 Leaky downstream gate valve.
F. Valve quickly and repeatedly fouls following servicing. F. Install finer mesh strainer element in the strainer.
F. Debris in pipe line is too fine to be
trapped by strainer.
G. Winterization of backflow preventers. G. Electric heat-tape wrap closely together around
valve body. Build a small shelter around the valve
with a large light bulb installed and left on at all times.
If supply line is not used during the winter, removal
of the complete body is the best. This would create
an air gap to eliminate any possible backflow.
7

For additional information, visit our web site at: www.watts.com
RP/IS-909/909RPDA 0829 EDP# 1915172 © 2009 Watts
USA: 815 Chestnut St., No. Andover, MA 01845-6098; www.watts.com
Canada: 5435 North Service Rd., Burlington, ONT. L7L 5H7; www.wattscanada.ca
A Watts Water Technologies Company