RP/IS-LF909S-FS
LF909-QT-S-FS
NOTICE
Use of the integrated flood sensor does not replicate the need to
comply with all required instructions, codes, and regulations related
to installation, operation, and maintenance of this product, including
the need to provide proper drainage in the event of a discharge.
Watts
®
is not responsible for the failure of alerts due to connectivity or
power issues.
NOTICE
The information contained herein is not intended to replace the full
product installation and safety information available or the experience
of a trained product installer. You are required to thoroughly read all
installation instructions and product safety information before begin-
ning the installation of this product.
Inquire with governing authorities for local installation requirements.
Installation, Maintenance, and Repair Manual
Series LF909-FS Small
Reduced Pressure Zone Assemblies
3
⁄
4
" – 2"
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.
Testing
For field testing procedure, refer to Watts
®
installation sheets
IS-TK-DL, IS-TK-9A, IS-TK-99E and IS-TK-99D at www.watts.com.
For other repair kits and service parts, refer to our Backflow
Prevention Products Repair Kits & Service Parts price list PL-RP-
BPD at www.watts.com.
For technical assistance, contact your local Watts representative.
Series LF909-FS Small is equipped with an integrated flood sensor
that, when activated, triggers notification of potential flood events
from excessive relief valve discharges. An add-on connection is
required to implement sensor activation. A retrofit sensor connection kit
is available for existing installations. See “Add-on and Retrofit Sensor
Connection Kits,” on the last page.
How It Operates
The unique relief valve construction
incorporates two channels: one for
air, the other for water. When the
relief valve opens, the right channel
admits air to the top of the reduced
pressure zone, relieving the zone
vacuum. The left channel then
drains the zone to atmosphere.
(See diagram to the right.) Therefore,
if both check valves foul, and
simultaneous negative supply and
positive backpressure develops, the
relief valve uses the air-in/water-out
principle to stop potential backflow.
Reduced
Pressure
Zone
Water Out
Air In
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 information is not consistent with local building or
plumbing codes, the local codes should be followed. This
product must be installed by a licensed contractor in ac-
cordance with local codes and ordinances.
WARNING
!
WARNING
!
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. If
installed on a fire suppression system, all mechanical checks,
such as alarms and backflow preventers, should be flow tested
and inspected in accordance with NFPA 13 and/or NFPA 25.
All products must be retested once maintenance has been
performed. 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 components helps assure maximum life and proper
product function.
NOTICE
For Australia and New Zealand, line strainers should be installed
between the upstream shutoff valve and the inlet of the backflow
preventer.
