Step 1
Remove the Grohe faucet's handle by unscrewing the handle's set screw, which is underneath the handle lever or on the handle base. Use a 2mm Allen wrench to remove the screw. Slide the freed handle off its location.
Step 2
Unscrew both screws in the faucet's trim plate with a screwdriver, and pull the trim plate off the shower wall. The trim plate is the round back-plate on the wall.
Step 3
Lift the cover off the faucet cartridge. The cover is a cylinder that hides the cartridge from view.
Step 4
Pull the adapter and limit stop off with your hands. The adapter is a rod-shaped part with a pin on top, and the limit stop is a round collar that fits over the cartridge stem. Place the adapter back in place with the pin facing upward and lined up with the arrow on the faucet.
Step 5
Turn the adapter, and use it to set the water temperature. Once it is set, not the number to which the pin points. Remove the adapter, and set the limit stop back on the faucet with the limit stop's notch facing the same number on the dial to which the adapter's pin pointed.
Step 6
Reassemble the faucet by replacing the adapter, cartridge cover, trim and handle. Tighten all corresponding screws.