I'm trying to increase hot water flow through bath tup faucet. I can only get handle to luke warm.

Is this problem isolated to just this faucet or is it common throughout the home?

What is the brand and the model number of your faucet?

John

I guess it is a single handle faucet. Remove handle. Behind the handle is safety stop. It is located on same stem that holds handle. It is either small black ring with lots of teeth or small brass washer with a protrusion. Remove it, toss it, reinstall handle. Now, you get max. hot water flow.