Installation, Maintenance, & Repair
Series 709/LF709/709DCDA
Double Check Valve Assemblies
Double Check Detector Assemblies
Sizes:
3
⁄
4
" – 10"
RP/IS-709/709DCDA
8" 709 OS&Y shown
Testing
For field testing procedure, reference IS-TK-DL, IS-TK-7,
IS-TK-9A, IS-TK-99E AND IS-TK-99D at www.watts.com
For other repair kits and service parts, reference PL-RP-BPD at
www.watts.com
For technical assistance, contact your local Watts
representative.
NOTICE
For Australia and New Zealand, line strainers should be in-
stalled between the upstream shutoff valve and the inlet of the
backflow preventer.
Its important that this device be tested periodically in compli-
ance with local codes, but at least once per year or more as
service conditions warrant. If installed on a fire sprinkler sys-
tem, all mechanical checks, such as alarm checks and back-
flow preventers, should be flow tested and inspected internally
in accordance with NFPA 13 and NFPA 25.
Installation Instructions
Watts Series 709 and LF709 Double Check Valve may be
installed in either a vertical or horizontal position - approvals
may vary by size/model. Refer to relevant ES sheet for com-
plete installation approval details.
Install valve inline with arrow on valve body pointing in the
direction of flow.
They should always be installed in an accessible location to
facilitate testing and servicing.
Pipe lines should be thoroughly flushed to remove foreign
material before installing the unit. A strainer should be installed
as shown, ahead of backflow preventers to prevent discs from
unnecessary fouling.
CAUTION
!
Do not install with strainer when backflow preventer is used on
seldom-used water lines which are called upon during emer-
gencies, such as fire sprinkler lines, etc.
It is important that Series 709 and LF709 be tested periodi-
cally in compliance with local codes, but at least once a year
or more often, depending upon system conditions. (Reference
IS-TK-7 at watts.com).
Clearance Required for Servicing
SIZE
DIMENSION
A
in.
in.
mm
2
1
⁄
2
" – 3
10
250
4
15
380
6
15
380
8
23
580
10
25
640
▼
▼
A
Local building or plumbing codes may require modifications to
the information provided. You are required to consult the local
building and plumbing codes prior to installation. If this informa-
tion 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. Corro-
sive 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
!
Read this Manual BEFORE using this equipment.
Failure to read and follow all safety and use information
can result in death, serious personal injury, property
damage, or damage to the equipment.
Keep this Manual for future reference.
