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Moen Solutions

Bathroom Faucet: Leaking Under The Sink Base

When a homeowner experiences a leaking faucet the first thing Moen needs to learn is the frequency of the leak, and the location where the leak is visible. This means we need to find out if the faucet has water appearing above the countertop also referred to as deck, or under the counter in the sink base vanity cabinet.  We also need the consumer to observe if they see the water dripping only as they use the faucet, directly after they use it for a short time, or continuously day and night. Each of these details will direct us to the correct solution for the problem. 

Leak above the deck: Symptoms include dripping from the end of the spout or leaking around the handle. For additional troubleshooting see Two Handle 8" Wide Spread: Lever or Two Handle 8" Wide Spread: Knob.

Leaking under the sink: Symptoms include steady or intermittent leaking. For additional information continue-


  1. Steady 24/7 Leak: The seals on the shut-off valves have failed, and water is leaking from around the handle(s) of the shut-off valves.
    • Solution: Replace the shut-off valves
  2. Steady 24/7 Leak: There is a split or tear in the supply lines that connect and deliver water from the shut-off up to the faucet lines
    • Solution: Replace the supply lines between the shut-off and the faucet.
  3. Intermittent Leak while using: The faucet supplies between the handle valves and the spout has developed a leak.
    • Solution: Replace the supply connection hose between the handle valves and the spout
      • Moen has used several style of connection hoses over the last few decades and you will need to determine which is used on your faucet. 
Identifying the Faucet Supply Connection Hose

Installed Prior to 2003

There are two generations of threaded hoses, see the images to the right for comparison.

14373-Prior to 2000


14373Built-in spout union T-connector 11111111


103469: Threaded spout with square brass connector


Installed 2003-2023


Moen has produced two color combinations of this style of quick-connect hose:

  • Three Black built-in quick-connects each built with an integrated white clip
  • Three White built-in quick-connects each built with an integrated black button
2020-08-27_14-15-56.png clipboard_e35b07cd1a560b266e456c82dcdca63d8.png

Installed 2023-Present


The quick-connect hose slides up the hot and cold valve bodies and snaps into place. The hose has white connectors with black elongated buttons.

Snag_e1901f1.png clipboard_eae5d8c72bbff7132cf7a7f03cdcec21f.png

For additional information on Moen products visit and select the type of product you are repairing. The guide will contain repair details, troubleshooting and specific information on assembling handles associated with that style of product.

Still Not Finding What You're Looking For?

Contact Us or Call 1-800-BUY-MOEN           

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