My home is only seven years old, I have a gas hot water heater and all faucets work fine, except the guess bathroom. The hot water flow is fine, but no hot water, no matter how long you run it. The faucets are delta that you "turn" on and off. Thank you for any advice you can provide. Have a nice day!

Not enough information. Lavatory, tub of shower valve? No other faucets in this bathroom are affected? Is this a one handled faucet or does it have two knobs? Let me know, Tom

If it is a single handle shower valve, it has a hot limiting cog under the handle. Remove the handle and adjust the cog.