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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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  • In the search box below, enter all or part of the part number or the part’s name.

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

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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

Symptoms for treadmills

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Why does my treadmill's walking belt slow down?

Main causes: damaged walking belt, improper belt tension, lack of belt lubricant, bad drive motor...

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Why is my treadmill's walking belt slipping?

Main causes: damaged walking belt, improper belt tension, bad roller bearing...

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Why is my treadmill's walking belt off center?

Main causes: rear roller out of alignment, damaged walking belt, bad roller...

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Why won't my treadmill start even though the console display works?

Main causes: missing safety key, bad control console, wiring failure, faulty motor control board, bad drive motor...

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Why is my treadmill's heart rate sensor not accurate?

Main causes: faulty sensors, wiring failure, bad control console...

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Why does my treadmill have no display?

Main causes: bad control console, wiring failure, bad motor control board...

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Why won't my treadmill power up?

Main causes: no power, bad power cord, tripped or faulty overload switch, bad power switch, wiring failure, bad motor co...

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Repair guides for treadmills

These step-by-step repair guides will help you safely fix what’s broken on your treadmill.

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How to replace a treadmill motor controller

How to replace a treadmill motor controller

Your treadmill motor won't run with a defective motor controller. Replace the motor controller if it doesn't operate the...

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Repair difficulty
Time required
15 minutes or less
How to replace a treadmill drive motor

How to replace a treadmill drive motor

A defective drive motor won't run when activated by the motor controller. Replace the treadmill drive motor if it doesn'...

Read more
Repair difficulty
Time required
15 minutes or less
How to replace a treadmill walking board

How to replace a treadmill walking board

A worn-out walking board creates friction with the walking belt and causes the belt to slow down during use. Replace the...

Read more
Repair difficulty
Time required
30 minutes or less

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5 Holiday Cleaning Tasks Essential to Boosting Your Home’s Image

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How to enjoy all the online benefits we offer on our Sears PartsDirect website

Learn about all the convenient features on our Sears PartsDirect website that make your parts purchases easier....

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Top questions about Sears and Sears PartsDirect

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