Install Instructions

3
1/2"
3/4" M2
1" M2
45
40
35
30
25
20
15
10
5
0
0 10 20 30 40 50 60 70 80 90 100 110
Flow Rate gpm
Flow Rate gpm
Zone Pressure psi
0 10 20 30 40 50 60 70 80 90 100 110
Zone Pressure psi
1
⁄4" – 1" (8 – 25mm) 919 and LF919
1
1
⁄4" – 2" (32 – 50mm) 919 and LF919
350
300
250
200
150
100
50
0
(32 – 40mm) (50mm)
1
⁄4"–
1
⁄2" c
3
⁄4" X 1"
(8 – 15mm) (20mm) (25mm)
0 1
1
⁄4"–1
1
⁄2" 2"
Figure 1
The relief vent discharges water during no-flow periods when:
(1) the first check valve is fouled; or
(2) the inlet pressure to the check valve drops sufficiently due to
upstream pressure fluctuations. This affects the required operat-
ing differential between the inlet pressure and the reduced pres-
sure zone; or
(3) the second check is fouled during emergency backflow or result-
ing from a water hammer condition.
For Troubleshooting Guide send for literature S-TSG.
NOTICE
When installing the Series 919
and LF919 on fire prevention
systems, special considerations
are required.
Fire Protection System
Installations: The National Fire
Protection Agency (NFPA)
Guidelines require a confirm-
ing flow test be conducted by a
certified tester whenever a “main
line” valve is installed, such as a
shutoff valve or a backflow pre-
venter.
Servicing the Relief Valve
WARNING
!
Depressurize valve before servicing.
No special tools are required to service the Series 919 and LF919
1
⁄4" - 2".
Before servicing, make sure the water is turned off or shutoff valves
are closed.
The following procedures provide information for replacing the
diaphragm, the relief valve disc, and the relief valve seat. It is rec-
ommended that you visually inspect these parts to determine if a
replacement or cleaning is required.
Disassembling the Relief Valve
1. Remove the relief valve cover bolts while holding the cover down.
2. Turn the cover counterclockwise for
1
⁄4 turn, and lift it straight off
while still applying pressure to the cover with your hand.
WARNING
!
Make sure you apply pressure to the cover as you lift it straight off.
Due to the release of pressure when removing the cover, the relief
valve spring may eject quickly.
3. Remove the relief valve assembly (includes cover O-ring, stem
and diaphragm assembly).
4. Remove the relief valve spring.
5. Remove the pressed in relief valve seat and seat O-ring.
Replacing the Diaphragm
6. Using a wrench, loosen the diaphragm assembly by turning the
hex bolt counterclockwise.
7. Remove the diaphragm and replace with a new diaphragm if
required, or clean the existing diaphragm.The molded step of the
diaphragm should point down towards the relief valve stem.
8. Using a wrench, reassemble the diaphragm assembly
by turning the hex bolt clockwise to tighten.
Replacing the Relief Valve Disc and Seat
9. Using a phillips screwdriver, remove the screw in the relief valve
disc and replace the disc if required, or clean the existing disc.
10. Place the screw back into the relief valve disc and tighten.
11. Replace the relief valve seat with a new seat if required, or clean
the existing seat.
Reassembling the Relief Valve
12. Place the relief valve seat back into the chamber bore.
13. Slide the diaphragm assembly into the relief valve seat.
14. Place the spring on to the diaphragm assembly.
15. Place the cover O-ring on the diaphragm assembly.
16. Line up the grooves on the relief valve cover with the grooves in
the relief valve body, and turn the cover clockwise
1
⁄4-turn to seat
the cover.
17. Using a wrench, place the bolts back into the cover and tighten.
CAUTION
!
If the cover does not
lie flat against the relief
valve body, the dia-
phragm assembly is
not installed properly
and damage can result.
Remove the bolts and
cover, realign the dia-
phragm assembly, and
place the cover back on
the relief valve body.
18. Open the shutoff
valves.
Watts
1
⁄4" – 2" 919 and LF919
*Vertical Flow Down
Floor Drain
Air
Gap
Elbow
Strainer
Quad-Ring
Relief Valve Cover O-ring
Diaphragm Nut
Relief Valve Diaphragm
Relief Valve Stem
Relief Valve Disc
Relief Valve
Disc Screw
Relief Valve Seat
Body
Relief Valve Seat O-ring
Relief
Valve
Spring
Relief
Valve
Cover
Cover
Bolts
TYPICAL FLOW RATES AS SIZED BY FLOOR DRAIN MANUFACTURERS:
2" (50 mm) 55 GPM 5" (125 mm) 350 GPM
3" (80 mm) 112 GPM 6" (150 mm) 450 GPM
4" (100 mm) 170 GPM 8" (200 mm) 760 GPM