Watts LF909 - Manual (Page 6)

1. Remove the four bolts that hold the relief valve cover in place.
2. Remove the cover. The stainless steel adapter, with O-ring
attached will be free to be removed simultaneous with the
removal of the cover. Pull out the relief valve assembly.
NOTICE
The spring tension in the relief valve assembly is contained in the
design of the relief valve; therefore, the relief can be removed in
a one-piece spool-type assembly.
3. The relief valve seat and disc may be cleaned without disassem-
bly of the relief valve assembly. If it is determined that the relief
valve diaphragm and/or disc should be replaced, the relief valve
module can be readily disassembled without the use of special
tools.
To Prevent Shaft Damage Assemble As Shown:
CAUTION !
If cover will not press against body, assembly is crooked and tightening bolts will bend shaft. Do not force the cover into place as damage
may result from misalignment.
Figure 1
Figure 2
Figure 3
Figure 1:
To assemble the Relief Valve Assembly
have a screwdriver ready.
Figure 2:
Depress the Relief Valve Assembly,
carefully guiding it against the two pound
spring load. When properly aligned, the
piston is in the cylinder bore. Insert the
screwdriver as shown.
Figure 3:
The Relief Valve Assembly is held
encapsulated by the screwdriver. You
should now have both hands free to
bolt down the cover. Insert and snug
two bolts 180° apart to hold the cover.
Finish inserting the remaining bolts and
snug up evenly, alternating until secure.
Remove the screwdriver.
Disc Assembly
Piston
O-ring
Relief Valve
Assembly
RV O-Ring
Stem
Seat
Body
Cover
Diaphragm
Piston
6
Cover
Seat
O-ring
Size 3 ⁄
4
” – 1”
Disc Assembly
(2) Piston
O-rings
Relief Valve
Assembly
(2) RV O-Rings
Stem
Seat
Diaphragm
Piston
Seat
O-ring
Size 1 1 ⁄
4
" – 2" (32-50mm)
For further details contact your local technical sales representative.
Servicing the Relief Valve 3 /
4
" to 2"
For repair kits and parts, refer to our Backflow
Prevention Products Repair Kits & Service Parts
price list PL-RP-BPD found on www.watts.com.