5
Servicing the First and Second Check Valves
1
⁄
2
" - 2" (15 - 50mm)
Test Cock No. 3
Cover Bolts
Seat O-ring
Seat
Disc
Assembly
Spring
Cage
Seat
Seat
O-ring
Disc
Assembly
Spring
Cage
Test Cock No. 2
Test Cock No. 1
Test Cock No. 4
Shutoff No. 2
Shutoff No. 1
Cover
Cover O-ring
First Check Assembly
Second Check Assembly
Relief Valve
Body O-ring
Relief Valve
Body
Seat
O-ring
Seat
Spring
Stem/Diaphragm
Assembly
Cover
Cover Nut
Sensing
Hose
Stem
O-ring
1. Close shutoff valves and open test cocks No. 2, 3 and 4 to
relieve pressure from the body of the valve. Loosen cover
bolts and remove cover. The check valve modules can now
be removed from the valve by hand or with a screwdriver.
Note: The first and second check assemblies are not inter-
changeable and the first check assembly must be removed
prior to removing the second check assembly.
2. The check assemblies are threaded into the valve body. To
remove the first check assembly, rotate the check module by
hand counterclockwise.
3. The second check assembly is removed by inserting the
blade of a screwdriver into two opposing slots of the seat as
shown in Figure 1 and rotate the check assembly counter-
clockwise.
4. The check seats are attached to the cage with a bayonet
type locking arrangement. Holding the cage in one hand,
push the seat inward and rotate clockwise against the cage.
The seat, cage, spring and disc assembly are now individual
components. If the cage disengages prematurely, simply use
the cage as a tool to screw the check valve seat from the
valve body.
5. The disc assembly may now be cleaned and reassembled or,
depending on its condition, it may be replaced with a new
assembly from a repair kit. Seat O-ring should be inspected
and replaced as necessary.
6. Reassemble the check module in the reverse order. Install the
check modules into the valve body hand-tight. Replace the
cover.
Figure 1
2nd Check Removal
For repair kits and parts, refer to our Backflow
Prevention Products Repair Kits & Service Parts
price list PL-RP-BPD found on
watts.com.
Summary of Contents for 995 Series
Page 7: ...7 Notes...
