I have a gas water tank and there is only lukewarm water flowing from all the faucets and showers.

Is your water lukewarm from the git-go or is it hot to start and turns cool after a bit? Regards, Tom

The water goes from cold to lukewarm. It never reaches the hot stage, no matter how long I keep the taps on.

It's possible that you have minerals built up on the floor of the tank that's acting as a insulator but the first thing I would check is bthe dip tube located directly under the cold water inlet. The purpose of a dip tube id to direct the cold water to the bottom of the tank where it won't mix and cool down the water at the top of the tank. If this tube were broken or has fallen down then you would be drawing cold water in with the draw making the water lukiewarm. Check the dip tube and let me know. Good luck, Tom

Dear Tom,
Being a widda lady from NY & moving to a wee little town of 700 people in South Carolina, I am actually learning a lot about hom repairs el solo... but when I took the front off the water heater (it is outdoors) I just could not locate the part you were speaking of. I did find the instruction manual inside and they suggested that the pilot light may have gone oit, but of course, I am a little itimidated by trying to relight a "gas" anything. I did have a gas heater recently installed for my pool, and as they are not quite done, this may be a contributing factor?? I believe my best bet would be to check with the gasman doing the pool heater... or contact my local gas company? Do these options sound feasible? I truly appreciate you taking the time to help me out

Let me explain about dip tubes. The image below shows how a dip tube works. The dip tube is the blue pipe on the right side of the water heater, notice that it goes almost all the way to the bottom of the water heater. The reason, is to force the cold water to the bottom and allow the hot water to come out of the left side of the water heater, notice there is no dip tube on the left side of the water heater. This image is not to scale and not up to code, it's only purpose is to show how the dip tube works. A water heater is always full of water, it does not empty, then fill again, the red in the tank represents hot water in the tank, the light blue represents cold water coming in to the tank. The image shows the tank going all the way from hot to cold, but if you have a water heater with a good recovery, the water heater will be able to keep heating the water, and prevent the water from ever getting cold. Almost all water heaters have dip tubes, Gas, electric, and oil fires, even indirect hot water makers have dip tubes, there are some that don't, if the cold water line is connected to the bottom of the water heater, there is no need for a dip tube. And now you know more then you ever wanted to know about dip tubes. This is what I think is broken but it's going to take some plumbing skills to0 replace it. At least if you call in a plumber you'll know what you're complaining about. Good luck, Tom

Hi Tom,
Every bit of knowledge is helpful, so I shall call the plumber in the morning and display my brilliant expertise. If anything, he might think I know what I'm talking about and not charge me an arm and a leg. Will let you know the aftermath. Thanks Linda