Install Instructions
Freeze Protection Guidelines
Purging of a PVB Assembly with Pressurized Air
Typical Installation
Using TWS Hydrant
Note: PVB's must be installed a minimum of 12" (305mm)
above the highest point of water in the sprinkler system.
Service and Replacement Parts
Internal parts can be removed, repaired or inspected without removing the valve from the piping.
Disassembly
1. Shut off the supply pressure and drain the valve.
2. Remove the two hood screws and the hood.
3. Place a wrench on the parallel flats of bonnet
and stem assembly. Turn counter clockwise
and remove.
4. Remove the vent assembly.
5. Press down on the spring retainer and disen-
gage it from the retaining lugs. Then turn 90°
and remove.
6. Remove the spring retainer and spring. Note that
the large diameter of the spring is down on the
guide assembly.
7. Remove the check disc holder and guide
assembly.
8. Disassemble the check disc holder assembly.
Reassembly
Reassemble in the reverse order utilizing the new
parts from the repair kit.
Ordering Size
Code Model in. mm
Check Kits
887703 *RK 800M4 CK
1
⁄2,
3
⁄4 15, 20
887704 *RK 800M4 CK 1 25
887705 *RK 800M4 CK 1
1
⁄4 - 2 32 - 50
Kits consist of: Check disc assembly (disc & disc holder). Bonnet 0-ring and Check Spring.
Vent Float Kits
887709 RK 800M4 V
1
⁄2,
3
⁄4 15, 20
887710 RK 800M4 V 1 25
887711 RK 800M4 V 1
1
⁄4 - 2 32 - 50
Kits consist of: Float vent disc assembly (vent float, seal & spring) and Bonnet 0-ring.
Freeze Protection Float Kit
887725 RK 800M4 FRV
1
⁄2,
3
⁄4 15, 20
887715 RK 800M4 FRV 1 25
887716 RK 800M4 FRV 1
1
⁄4 - 2 32 - 50
Kit consists of: Float, vent spring and Bonnet O-ring.
Bonnet Assembly Kits
887700 RK 800M4 B
1
⁄2,
3
⁄4 15, 20
887701 RK 800M4 B 1 25
887702 RK 800M4 B 1
1
⁄4 - 2 32 - 50
Kits consist of: Bonnet, Bonnet O-ring, Vent spring, hood & hood screws.
Ordering Size
Code Model in. mm
Rubber Parts Kits
887706 RK 800M4 RT
1
⁄2,
3
⁄4 15, 20
887707 RK 800M4 RT 1 25
887708 RK 800M4 RT 1
1
⁄4 - 2 32 -50
Kits consist of: Vent disc, Check disc and Bonnet O-ring.
Seat Kits
887712 RK 800M4 S
1
⁄2,
3
⁄4 15, 20
887713 RK 800M4 S 1 25
887714 RK 800M4 S 1
1
⁄4 - 2 32 - 50
Kits consists of: Seat, Seat O-ring and Bonnet O-ring.
To
Sprinklers
Key
Drain Port
or
Blow Down
Water
Supply
Watts TWS
TWS with Watts 800 Series
Pressure Vacuum Breaker
800M4 Repair Kits
1. Close main shutoff valve.
2. Open upstream drain, test cocks and isolation
ball valves to depressurize line.
3. Purge with pressurized line.
4. Leave test cocks and isolation ball valve
handles in 45° angle to drain ball valves and
prevent casting damage.
Watts 800M4QT
1" - 2" (25 - 51mm)
Watts 800M4QT
1
⁄2",
3
⁄4" (13, 19mm)
Watts reserves the right to change or modify product design, construc-
tion, specifications, or materials without prior notice and without incur-
ring any obligation to make such changes and modifications on Watts
products previously or subsequently sold.
Outlet Drain
Valve
12" Minimum Clearance
Above the Highest Point of
Downstream Piping
Zone Control
Valve Pit
Sprinkler System
Piping
Flow
Union
Main Shutoff Valve
Upstream (Inlet) Drain
▼
▼
For Retrofit of Models M2 & M4 to M4FR
Ordering Size
Code Model in. mm
887726 Retro 800M4 FR
1
⁄2,
3
⁄4 15, 20
887717 Retro 800M4 FR 1
1
⁄4 - 2 32 - 50
Kits consist of: Float, spring, Bonnet and Bonnet O-ring.
Note: *Fits 800M4 FR Model
RP/IS-800M4QT 0904 EDP# 1915087 © Watts, 2009
USA: 815 Chestnut St., No. Andover, MA 01845-6098; www.watts.com
Canada: 5435 North Service Rd., Burlington, ONT. L7L 5H7; www.wattscanada.ca
Water Safety & Flow Control Products