Watts LF919-QT-FS, Instruction, Installation, Maintenance And Repair Manual

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4
Servicing the Relief Valve
WARNING
!
Depressurize valve before servicing.
No special tools are required to service the assembly.
Before servicing, turn off the water or close the shutoff valves.
Remove the flood sensor and activation module if the relief
valve outlet needs to be cleaned of debris.
The following procedures provide information for replacing
the diaphragm, the relief valve disc, and the relief valve seat.
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 by one quarter, and lift it
straight off while still applying pressure to the cover with
your hand.
WARNING
!
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
1. Using a wrench, loosen the diaphragm assembly by turning
the hex bolt counterclockwise.
2. 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 toward the relief
valve stem.
3. Using a wrench, reassemble the diaphragm assembly
by turning the hex bolt clockwise to tighten.
Replacing the Relief Valve Disc and Seat
1. Using a Phillips screwdriver, remove the screw in the relief
valve disc and replace the disc if required, or clean the
existing disc.
2. Place the screw back into the relief valve disc and tighten.
3. Replace the relief valve seat with a new seat if required, or
clean the existing seat.
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
Reassembling the Relief Valve
1. Place the relief valve seat back into the chamber bore.
2. Slide the diaphragm assembly into the relief valve seat.
3. Place the spring onto the diaphragm assembly.
4. Place the cover O-ring on the diaphragm assembly.
5. Line up the grooves on the relief valve cover with the
grooves in the relief valve body, and turn the cover clock-
wise by one quarter to seat the cover.
6. 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
diaphragm 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.
7. Reinstall the flood sensor and activation module if removal
was required.
8. Open the shutoff valves.
DRAFT
5. Remove the pressed-in relief valve seat and seat O-ring. 5. Remove the pressed-in relief valve seat and seat O-ring.
1. Using a wrench, loosen the diaphragm assembly by turning 1. Using a wrench, loosen the diaphragm assembly by turning
2. Remove the diaphragm and replace with a new diaphragm 2. Remove the diaphragm and replace with a new diaphragm
if required, or clean the existing diaphragm. The molded if required, or clean the existing diaphragm. The molded
step of the diaphragm should point down toward the relief step of the diaphragm should point down toward the relief
3. Using a wrench, reassemble the diaphragm assembly 3. Using a wrench, reassemble the diaphragm assembly
by turning the hex bolt clockwise to tighten. by turning the hex bolt clockwise to tighten.
Replacing the Relief Valve Disc and Seat Replacing the Relief Valve Disc and Seat
1. Using a Phillips screwdriver, remove the screw in the relief 1. Using a Phillips screwdriver, remove the screw in the relief
valve disc and replace the disc if required, or clean the valve disc and replace the disc if required, or clean the
existing disc. existing disc.
2. Place the screw back into the relief valve disc and tighten. 2. Place the screw back into the relief valve disc and tighten.
3. Replace the relief valve seat with a new seat if required, or 3. Replace the relief valve seat with a new seat if required, or
clean the existing seat. clean the existing seat.
DRAFT DRAFT DRAFT DRAFT DRAFT DRAFT DRAFT DRAFT DRAFT DRAFT DRAFT DRAFT DRAFT DRAFT DRAFT
Quad-Ring Quad-Ring
Relief Valve Cover O-ring Relief Valve Cover O-ring
Reassembling the Relief Valve Reassembling the Relief Valve
1. Place the relief valve seat back into the chamber bore. 1. Place the relief valve seat back into the chamber bore.
2. Slide the diaphragm assembly into the relief valve seat. 2. Slide the diaphragm assembly into the relief valve seat.
3. Place the spring onto the diaphragm assembly. 3. Place the spring onto the diaphragm assembly.
4. Place the cover O-ring on the diaphragm assembly. 4. Place the cover O-ring on the diaphragm assembly.
5. Line up the grooves on the relief valve cover with the 5. Line up the grooves on the relief valve cover with the
grooves in the relief valve body, and turn the cover clock- grooves in the relief valve body, and turn the cover clock-
wise by one quarter to seat the cover. wise by one quarter to seat the cover.
6. Using a wrench, place the bolts back into the cover and 6. Using a wrench, place the bolts back into the cover and