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.

There are a couple of ways to find the part or diagram you need:

  • Click a diagram to see the parts shown on that diagram.
  • 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”.

We encourage you to save the model to your profile, so it’s easy to access parts and manuals for your appliance whenever you log in.

For DIY troubleshooting advice and repair guides, visit our repair help section.

Model diagram and schematic

SEARCH WITHIN THIS MODEL

?

This is the number corresponding to the part on the diagram / schematic

Search
ALL PARTS
Showing 10 of 45 parts  |

Plate 135B66-M2
#9B

Replacement parts diagram

Plate

Part #135B66-M2

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

Lock Washer 174C46
#8

Replacement parts diagram

Lock washer

Part #174C46

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

Disc Holder 50B47
#15A

Replacement parts diagram

Disc holder

Part #50B47

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

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

Spring 124
#5A

Replacement parts diagram

Spring

Part #124

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

Strain Plug 18Y2
#19A

Replacement parts diagram

Strain plug

Part #18Y2

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

Service Kit 5B

#NI

All parts diagram

Service kit

Part #5B

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

Effective articles & videos to help repair your room air conditioners

Tapping into a new feature in the Search Bar on Sears PartsDirect

Tapping into a new feature in the Search Bar on Sears PartsDirect

Learn about a new feature added to the Search Bar on Sears PartsDirect…

How to tell if a fuse is blown

How to tell if a fuse is blown

Learn how to tell whether a fuse is blown…

Keeping your smart appliances secure from hackers

Keeping your smart appliances secure from hackers

Find out how to protect your smart appliances from malevolent invasions by hackers.…