Welflos M Replacement Reservoir Plug Installation Guide

By Weldental: Water Flosser with Weltip Infuser Tip Delivers | Published: 2026-10-19

Category: How-to Guides

Learn how to replace the Welflos M reservoir plug to fix water flow issues. Step-by-step instructions with common mistakes to avoid.

Quick Answer

Replace the Welflos M reservoir plug from the inside of the water reservoir, twisting it to seat properly and ensuring it moves up and down easily to restore normal water flow.

Why the Plug Matters

The reservoir plug in your Welflos M water flosser is a small but critical part. It seals the reservoir and allows water to flow correctly during use. If it wears out or becomes misaligned, you may notice reduced water pressure or leaks.

Replacing the plug is a simple DIY fix that can save you from buying a new device. However, it's important to install it correctly to avoid recurring issues.

Signs You Need a New Plug

Common indicators that the reservoir plug needs replacement include inconsistent water flow, water leaking from the reservoir, or the plug appearing cracked or deformed.

If you experience any of these issues, replacing the plug is the first step before considering more complex repairs.

Step-by-Step Installation

Remove the old plug: Turn the reservoir upside down and gently push the old plug out from the inside. If it's stuck, use a soft tool to avoid damaging the reservoir. Check the old plug for cracks or wear to confirm replacement is needed.
Position the new plug correctly: Identify the top and bottom of the new plug. The top is the image on the right, and the bottom is the image on the left. Insert the plug from the inside of the reservoir, ensuring the correct side faces up. Mistake to avoid: inserting the plug upside down, which can cause poor sealing.
Twist and seat the plug: Twist the plug gently to seat it properly in the opening. It should fit snugly without forcing. If it doesn't twist easily, remove and recheck orientation.
Test the movement: Move the plug up and down to ensure it slides freely. It should move easily without sticking. If it sticks, re-twist to align it better.
Reassemble and test the flosser: Reattach the reservoir to the flosser, fill with water, and run the device to check for normal water flow and any leaks. If flow issues persist, check other parts like the pump or hose.

What You Need

Welflos M replacement reservoir plug: Replacing the reservoir plug usually corrects water flow issues. Insert the new plug from the inside of the water reservoir. The top is the image on the right, and the bottom is the image on the left. Twist the plug to seat it properly and make sure it moves up/down easily. Ensures correct orientation and a secure fit, preventing future leaks or flow problems.
Welflos M replacement reservoir plug