Verified model passport / Watts
800M4 / LF800M4QT
Pressure vacuum breaker
The 800M4 repair family repeats across size bands, but the part-number suffix and eligible model designation change. Select the exact band before comparing kit scope.
Watts publishes 800M4FR, 800M4QT, and LF800M4 variants. Confirm the complete body label because some retrofit, freeze-sensor, and repair kits have narrower compatibility.
Compatibility workstation
Match the size and repair scope.
Use the complete model label, nominal body size, and failed component. The tool only exposes combinations found in the cited manufacturer material.
Choose a size band to reveal compatible published kits.
Total repair kit
Check, vent-float, bonnet, and seat repair-kit groups.
Bonnet kit
Bonnet, bonnet O-ring, vent spring, hood, and hood screw.
Check kit
Check disc assembly, bonnet O-ring, and check spring.
Rubber parts kit
Vent seal, check disc, and bonnet O-ring.
Total repair kit
Check, vent-float, bonnet, and seat repair-kit groups.
Bonnet kit
Bonnet, bonnet O-ring, vent spring, hood, and hood screw.
Check kit
Check disc assembly, bonnet O-ring, and check spring.
Vent float kit
Float vent disc assembly and bonnet O-ring.
Total repair kit
Check, vent-float, bonnet, and seat repair-kit groups.
Bonnet kit
Bonnet, bonnet O-ring, vent spring, hood, and hood screw.
Check kit
Check disc assembly, bonnet O-ring, and check spring.
Rubber parts kit
Vent seal, check disc, and bonnet O-ring.
Identity check
Confirm this model before ordering.
Similar-looking assemblies can use different internals. A search result or pipe size alone is not enough.
- 01
The full label may include 800M4QT, LF800M4QT, 800M4FR, or LF800M4FR.
- 02
A bonnet kit, vent-float kit, and check kit repair different assemblies.
- 03
Retrofit and freeze-sensor kits are not interchangeable with internal repair kits.
Before return to service
A matching kit is not a passed assembly.
Stop for body damage. Cracks, distortion, severe corrosion, or freeze damage can move the job from internal service to replacement.
Test after repair. Where the assembly is regulated, the governing utility or authority decides tester approval, reporting, and deadlines.
Use the current instructions. Part references can change. Confirm availability and supersession with the manufacturer or an authorized supplier.
Find the governing utilityOfficial source ledger
Trace every compatibility claim.
No retailer copy is used as the authority for the kit map.
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