A stuck anti-scald button can make a shower hard to use.
It can also make the water feel too hot.
Many shower handles use a safety stop.
This stop helps limit how far the handle turns.
The red button is often part of that safety stop.
You press it to move past a set temperature point.
If it sticks, the handle may not move as it should.
That can make the shower feel locked in place.
In this case, the shower is a MAAX brand unit.
The red button will not push in.
CLR was added to the button.
But it did not free the part.
The handle also does not look easy to remove.
Before forcing anything, slow down.
Shower trim parts can crack.
Small plastic buttons can also break.
A broken part may be hard to match later.
Question
I have an anti-scald red button on my shower knob.
I cannot push it to lower the heat.
CLR did not seem to help.
I also cannot figure out how to remove the knob.
It is a MAAX brand shower.
What should I do next?
Answer
Do not force the red anti-scald button.
First, shut off the water if needed.
Then look for a hidden set screw under the handle.
The screw may be under a cap, plug, or trim cover.
If the button is jammed, the handle may need removal and cleaning.
Start by checking the handle closely.
Look under the lever or knob.
Use a flashlight if the bathroom is dim.
Many handles use a small Allen screw.
Others hide a screw behind a snap-on cap.
If you find a screw, loosen it gently.
Do not strip the head.
Pull the handle straight off.
Do not twist hard against the wall.
That can damage the valve stem.
Once the handle is off, inspect the red button.
Mineral buildup may be holding it.
Dried soap can also make it stick.
Clean around the button with warm water.
Use a soft brush or an old toothbrush.
CLR can help with minerals.
But it may not reach the stuck part.
It can also harm some finishes.
Always follow the product label.
Rinse the area well after use.
If the button still will not move, stop there.
The cartridge or temperature limit stop may be damaged.
You may need a replacement trim part.
You can check the MAAX website for product support and model information.
If you do not know the model, take clear photos.
Include the handle, trim plate, and shower wall.
A plumbing supply store may match the part.
A plumber can also identify the valve faster.
Do not remove the valve cartridge unless you are ready.
Water may need to be shut off first.
Some homes lack shower shutoff valves.
That means the main water valve may be needed.
The safest plan is simple.
Find the hidden screw.
Remove the handle carefully.
Clean the button from behind.
Replace worn parts if cleaning fails.
I’m Chris Mayer, writing for Plumbing 101.
