Watts
Plumbing

Model # 1789 Official Watts 3/4" water pressure reducing valve

Here are the diagrams and repair parts for Official Watts 1789 3/4" water pressure reducing valve, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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Showing 10 of 45 parts  |

Union Nut 35A140
#21A

Replacement parts diagram

Union nut

Part #35A140

The manufacturer no longer makes this part, and there's no substitute part

Service Kit 5A

#NI

All parts diagram

Service kit

Part #5A

The manufacturer no longer makes this part, and there's no substitute part

Stem & Seal SA-50B27
#11A

Replacement parts diagram

Stem & seal

Part #SA-50B27

The manufacturer no longer makes this part, and there's no substitute part

Strain Plug 18Y2
#19A

Replacement parts diagram

Strain plug

Part #18Y2

The manufacturer no longer makes this part, and there's no substitute part

Seat 50B16
#12A

Replacement parts diagram

Seat

Part #50B16

The manufacturer no longer makes this part, and there's no substitute part

Strainer 4500A77
#20B

Replacement parts diagram

Strainer

Part #4500A77

The manufacturer no longer makes this part, and there's no substitute part

Lock Washer 174C46
#8

Replacement parts diagram

Lock washer

Part #174C46

The manufacturer no longer makes this part, and there's no substitute part

Union Tailpc 135A139
#23A

Replacement parts diagram

Union tailpc

Part #135A139

The manufacturer no longer makes this part, and there's no substitute part

Union Nut 35B140
#21B

Replacement parts diagram

Union nut

Part #35B140

The manufacturer no longer makes this part, and there's no substitute part

Stem & Seal SA-50C27
#11B

Replacement parts diagram

Stem & seal

Part #SA-50C27

The manufacturer no longer makes this part, and there's no substitute part