Hello, it may seem that your ceramic cartridge (QTLS121) is experiencing problems.
In order to resolve your situation please follow the steps below:
1- First and foremost close your main valves. 2- Remove the lever by hand. 3- You will see a hex screw, remove that screw with an Allen Key. 4- Remove the cap by hand turning counter clock wise. 5- You will see a brass ring with two flat edges, apply pliers or a vise grip turning counter clock wise, without touching the threads. 6- If difficult to remove, reason being there is calcium build up, apply DW-40 or similar. 7- Pull out ceramic cartridge and reply new one with in the slots. 8- Screw on the brass ring without touching the threads 9- Reapply the rest of the pieces. 10- Please note, make sure your faucet is completely opened when opening of your water main and when opening the water , please open slowly to prevent water hammering (air pockets ) in your line.
We hope that this answers your question, if you have any other issues please do not hesitate to contact one of our specialists by phone at 1-877-333-0098 (option 1 after selecting your language).
Conglom Kitchen & Bath Customer Service Team