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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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Model diagram and schematic

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Showing 10 of 45 parts  |
Gasket 215Y102
#18A

Replacement parts diagram

Gasket

Part #215Y102

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

Service Kit 5C

#NI

All parts diagram

Service kit

Part #5C

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

Diagram 135B20
#10B

Replacement parts diagram

Diagram

Part #135B20

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

Spring 124
#5A

Replacement parts diagram

Spring

Part #124

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

Gasket 1-1/2X1-3/4
#16A

Replacement parts diagram

Gasket

Part #1-1/2X1-3/4

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

Seat 50C16
#12B

Replacement parts diagram

Seat

Part #50C16

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

Plug N36A2
#17A

Replacement parts diagram

Plug

Part #N36A2

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

Plug 37A2-1
#19B

Replacement parts diagram

Plug

Part #37A2-1

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

Disc Holder 50C47
#15B

Replacement parts diagram

Disc holder

Part #50C47

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

Plate 135B66-M2
#9B

Replacement parts diagram

Plate

Part #135B66-M2

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

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