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Watts
Plumbing

Model # 1788 Official Watts 1/2" water pressure reducing valve

Here are the diagrams and repair parts for Official Watts 1788 1/2" water pressure reducing valve, as well as links to manuals and error code tables, if available.

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Not all parts are shown on the diagrams—those parts are labeled NI, for “not illustrated”.

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Error Codes

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ALL PARTS
Showing 10 of 45 parts  |
Disc Holder 50C47
#15B

Replacement parts diagram

Disc holder

Part #50C47

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

Lock Nut 30AL51
#7

Replacement parts diagram

Lock nut

Part #30AL51

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

675.4 (1/2") 56C8102
#22A

Replacement parts diagram

675.4 (1/2")

Part #56C8102

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

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 135C139
#23C

Replacement parts diagram

Union tailpc

Part #135C139

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

Washer 45A62
#4

Replacement parts diagram

Washer

Part #45A62

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

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

Union Nut 35C140
#21C

Replacement parts diagram

Union nut

Part #35C140

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

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