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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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Error Codes

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ALL PARTS
Showing 10 of 45 parts  |
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 Seal 35C103
#22C

Replacement parts diagram

Union seal

Part #35C103

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

Adjustment Nut 30B33
#2

Replacement parts diagram

Adjustment nut

Part #30B33

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

Adjusting Screw (3/8-16 X 2") N/P
Adjusting screw (3/8-16 x 2")

Part #N/P

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

Diagram 135A20
#10A

Replacement parts diagram

Diagram

Part #135A20

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

Disc 50C37
#14B

Replacement parts diagram

Disc

Part #50C37

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

Most common symptoms to help you fix your dishwashers

Choose a symptom to see related dishwasher repairs.

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Why won't my dishwasher fill?

Main causes: water supply problem, stuck overfill float, clogged water inlet valve screen, water inlet valve failure…

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Why won't my dishwasher start?

Main causes: light switch beside the sink turned off, lack of power, bad dishwasher door switch, control system failure,…

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Why can't I adjust the dishwasher rack height?

Main cause: damaged rack height adjuster…

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Why won't my dishwasher drain?

Main causes: clogged kitchen sink drain, clogged drain hose, drain check valve damaged, drain pump failure, control syst…

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Why isn't my dishwasher getting dishes clean?

Main causes: improper loading, low water temperature, improper detergent dosage, detergent dispenser failure, spray arm …

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Why is my dishwasher leaking?

Main causes: damaged or stuck spray arm, leaking door seal, damaged door hinge, leaky heating element water seal, cracke…

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Why don't my dishes get dry?

Main causes: not using rinse aid, rinse aid dispenser failure, broken heating element, malfunctioning vent, drying fan f…

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Why does my dishwasher door drop open too fast?

Main causes: broken door spring, damaged or broken door hinge…

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Why does my dishwasher stop mid-cycle?

Main causes: broken door latch, tripped circuit breaker, broken heating element, faulty vent fan, sensor failure, contro…

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Most common repair guides to help fix your dishwashers

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

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How to replace a dishwasher water inlet valve

How to replace a dishwasher water inlet valve

If your dishwasher fills constantly or won't fill at all, the water inlet valve has failed. You can replace it in about …

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Repair difficulty
Time required
 30 minutes or less
How to replace a dishwasher timer

How to replace a dishwasher timer

Follow these steps to replace the timer in your dishwasher if it fails to advance or does not operate properly.…

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Repair difficulty
Time required
 15 minutes or less
How to replace a dishwasher lower spray arm

How to replace a dishwasher lower spray arm

If the lower spray wash arm is damaged, you can install a new one in just a few minutes.…

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Repair difficulty
Time required
 15 minutes or less

Effective articles & videos to help repair your dishwashers

Use the advice and tips in these articles and videos to get the most out of your dishwasher.

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How to use your dishwasher efficiently

How to use your dishwasher efficiently

Get expert tips on using your dishwasher efficiently to save water and energy.…

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How to clean and maintain your dishwasher

How to clean and maintain your dishwasher

Get tips for cleaning and maintaining your dishwasher…

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Dishwasher has power but won't run? Could be demo mode

Dishwasher has power but won't run? Could be demo mode

This list shows how to disable the demo mode on a variety of dishwashers.…

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