How Does a Bathtub Trip Lever Work?

A bathtub trip lever is likely a feature you use every time you take a bath, but have you ever wondered how it actually functions to drain and fill your tub? The trip lever is the handle mechanism mounted on your tub’s exterior that controls the drain and water flow with a simple pull up or push down. This indispensable bath fixture relies on a series of internal linkages and valves to perform its wet work.

Understanding how a trip lever works can help you diagnose and repair issues like a stuck lever or problems with draining or filling. While you can always call a plumber, some trip lever troubles can be fixed DIY-style if you know how the components interact. Let’s take a deep dive into the anatomy of a bathtub trip lever.

How Does a Bathtub Trip Lever Work?

A bathtub trip lever is connected to a plunger that seals or opens the drain. When you flip the trip lever up, it lifts the plunger to block the drain, allowing the tub to fill. Flipping the trip lever down drops the plunger, so the drain opens and the tub empties. The trip lever gives you an easy way to control draining without plugging/unplugging the drain manually.

Main Components of a Trip Lever

When you pull or push a bathtub trip lever, you are activating several components inside the tub wall:

• Lever handle – The movable external handle that the user pulls up or pushes down to operate the drain and fill functions. Usually made of metal or plastic.
• Linkage rods – Long metal rods that connect the external lever handle to the internal drain and fill valves.
• Plunger/stopper – A rubber stopper inside the drain pipe that seals the drain closed when pushed down by the trip lever linkage.
• Drain valve – The actual drain control device located inside the drain pipe system that stops or allows water to flow when opened or closed by the trip lever.
• Fill valve – The water control valve connected to the tub’s faucet supply line that turns on or shuts off water flow in response to the trip lever position.

The major components of a bathtub trip lever.

These essential trip lever pieces work together to manipulate the drain and water flow as the lever is moved up and down. The linkage rods transfer the lever handle motion to the drain and fill valves concealed inside the tub walls to produce the desired action.

How Does Pulling the Trip Lever Drain the Tub?

When you are ready to drain a filled bathtub, here is what happens when you pull up on the trip lever to the open position:

1. The linkage rod connecting the exterior lever to the drain plunger lifts up the plunger inside the drain pipe.
2. Lifting the plunger allows the water in the tub to drain freely down the open drain pipe.
3. The weight and pressure of the water in the full tub causes it to drain out the opened drain due to gravity.
4. As the water level drops, it continues flowing down the drain pipe until the tub empties.
5. The tub can only drain as fast as the diameter of the drain pipe system allows. Standard 1.5-inch pipes drain tubs slower than larger 2-inch pipes.

The upward motion of the trip lever handle is transferred through the linkage to lift the drain plunger. This stopper is what seals the drain closed when you push the trip lever down. Lifting the plunger with the pull-style movement breaks the watertight seal and enables gravity drainage.

How Does Pushing the Lever Down Fill the Tub?

The flip side of the trip lever operation involves controlling the bathtub faucet to fill the tub with water:

1. When you push the trip lever down to the closed position, it moves a second linkage rod connected to the fill valve.
2. This rod opens the fill valve located on the tub’s supply line, allowing water to flow from the faucet.
3. At the same time, the first linkage connected to the drain plunger pushes the stopper down to seal the drain pipe closed. This prevents the water from immediately flowing out the drain.
4. With the drain closed and the fill valve open, water pours from the faucet to fill the bathtub.
5. Pushing the lever down also typically initiates the hot and cold water mixing to your preset temperature.
6. As the tub reaches your desired fill level, you pull the trip lever up to close the fill valve and stop the water.

Again, the trip lever transfers your push-down motion to manipulate the concealed drain and fill valves in order to fill the bathtub on command.

Common Trip Lever Problems

While bathtub trip levers are designed to operate smoothly for years, complaints about stuck, broken, or leaky trip levers are fairly common. Here are some of the most frequent trip lever troubles:

• Stuck lever – The external lever becomes stuck in the up or down position. This may prevent draining or filling the tub. Gunk buildup or loose linkages are often the culprit.
• Drain won’t close fully – Pushing the lever down does not fully seal the drain closed, resulting in slow leaks and failure to hold water. An issue with the plunger seal or linkage alignment is likely.
• Fill valve won’t shut off – The fill valve fails to close completely when the lever is pulled up. Usually caused by debris or mineral buildup on the valve seat. Running water will result.
• Dripping faucet – Water drips from the tub faucet constantly, showing the fill valve is not closing completely. Valve seat issue or unbalanced water pressure typically responsible.
• Corroded linkage rods – Age and rust causes the metal linkage rods to degrade and bind, impeding their movement. Replacement rods are needed.

Trip Lever Problem	Likely Causes	Solutions
Stuck lever	Gunked up mechanism, loose linkage rod	Disassemble and clean inside parts, tighten loose hardware
Drain won’t close fully	Plunger seal failure, misaligned linkage	Replace plunger seal, realign rods
Fill valve won’t shut off	Debris obstruction, mineral deposits	Clean or replace fill valve
Dripping faucet	Damaged fill valve, unbalanced pressure	Repair/replace fill valve, use pressure balance valve
Corroded linkage rods	Age, rust, mineral deposits	Replace rusted linkage rods

Common bathtub trip lever issues, potential causes, and solutions.

While some trip lever problems require professional help, many can be DIY fixes with some persistence.

Replacing a Broken or Stuck Trip Lever

If cleaning and troubleshooting cannot restore smooth operation, replacing the entire trip lever mechanism may be needed. Follow these steps to remove the old unit and install a new trip lever:

Gather the following tools:

• Flathead screwdriver
• Adjustable wrench
• Teflon plumber’s tape
• Silicone caulk
• Replacement trip lever kit

Removing Old Trip Lever:

1. Turn off water supply lines to the tub and open the drain fully.
2. Remove decorative trim plate or cap concealing lever screws.
3. Disconnect and remove linkage rods if possible.
4. Unscrew mounting nuts to detach lever from exterior.
5. Remove remaining nuts and linkage hardware from interior.

Installing New Trip Lever:

1. Apply plumber’s tape to threaded fittings on new lever and valves.
2. Attach new lever exterior and fasten mounting screws.
3. Connect new linkage rods between handle and plunger and fill valves.
4. Confirm proper fit of drain plunger and fill valve function.
5. Caulk around new exterior trim plate for water seal.

Testing Operation:

1. Turn tub water supply back on and check for leaks during operation.
2. Pull lever up to drain tub fully and ensure it seals closed when pushed down.
3. Push lever down to check fill valve shuts off completely when lever is pulled up.
4. Make any adjustments needed to linkages.

Replacement trip lever kits are available at most hardware stores and home improvement centers if you need new parts. With some handy work, you can install a smooth functioning trip lever.

FAQs

What is the bathtub lever called?

The lever mounted on the exterior of a bathtub that controls draining and filling is called a trip lever or tub lever.

Why won’t my bathtub lever lift to drain?

If the tub lever won’t lift up to drain, it is likely due to buildup gumming up the mechanism, a loose linkage rod, or a damaged drain stopper seal.

How do I remove bathtub trip lever?

Remove any trim plate, disconnect linkage rods if possible, unscrew mounting nuts, and pull the old trip lever unit out from the tub exterior.

What side should tub lever be on?

The tub lever can be installed on either side, but is usually placed on the right side of the tub for convenience.

How do I fix a bathtub trip lever that won’t close?

For a trip lever that won’t close the drain fully, try realigning the linkage rods or replacing the drain stopper seal or assembly.