I'm having a problem with my hot water: sometimes it's not so hot. When I take a shower, I like the water to be quite hot, and half the time it is fine. But roughly half of my mornings, the water is not as hot as I would like. This is odd, since I am always the first one to use the shower or hot water each day, so it's not as if someone else has used up the hot water. When this happens, I usually turn the cold water all the way off, and the water still is only lukewarm. Could this be a thermostat problem on my hot water heater? It's a gas heater, and not more than 10 years old.

It sounds like a gas valve problem. For starters, turn the gas valve all the way up to the hottest setting and see if this makes any difference. If the problem gets worse, call a plumber

Bob gave you good advice. Let me add to it. Do you flush out the mineral buildup on a regular basis? If not mineral buildup at the botton of the tank may be robbing you of hot water. To flush- attach a hose to the boiler drain located at the bottom of the tank. Now WITH THE WATER LEFT ON open the boiler drain. You will see a spurt of red,(rust) followed by white or yellow grains,(calcuim carbonate or lime). Leave it until the water runs clear. It will only take a few minutes. Do this on a regular basis and your heater will thank you for it. Good luck, Tom