Hot water last long time everywhere but in my shower?
Hot water only lasts about 10 minutes in shower but lasts forever in kitchen and bathroom sinks!
How can I fix this?
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Unless something is badly broken in your setup, the most effective fixes are (1) installing a flow restrictor, (2) increasing your water tank size, and (3) raising your water heater temperature.
You're probably just using up all the hot water in the tank. You can confirm this if you have a 5 gallon bucket (you can get one for a few bucks in my neighborhood big box store). Stick it under your shower head and see how long it takes to fill halfway. A modern shower head will take about a minute to fill 2.5 gallons, which if it's 80% hot water and 20% cold, means you're using 2 GPM hot water. If you have a smaller 40 gal tank, you have 20 minutes of shower. But if you had an older shower head (probably your case), it could have easily have twice the flow, meaning you have 10 minutes.
You can lengthen your shower using any of the suggested techniques, the easiest and most effective being replacing your shower head. In many places, your utility will give you a water-efficient shower head for free.
My bathroom sink is 1.2 GPM, and most are similar, which would give you 40 min hot water in the same setup.
Sounds like the shower is using too much water in general. If you have a strong, powerful stream coming out of the shower head, it probably has its water restrictor removed, or its old enough to not have one. You might not be totally happy with the new spray, but a new shower head would use less water and therefore give a longer shower.
If the water is just getting warm after 10 minutes and not totally cold, then your single handle faucet might need some adjustment. Those can be set to use only a certain amount of hot water to control the max temp of the shower. If your hot water drops in temperature after a few minutes, your shower temp will drop, and you won'y be able to "turn it up" because it's already on max hot.
Have you thought about a hot water mixing valve? It tempers the hot water coming out of your water heater with cold water to achieve the desired temp (recommend 120 degrees). Then you can turn up the tstats on the WH to 140 or 150 effectively increasing the "size" of the WH without actually replacing it.
You have a high-flow shower head, which is basically dumping your entire hot water tank in minutes, wasting your limited time of water.
A low-flow head will perform much better for you.
Massive amounts of water coming down isn't a tenth as useful as people think it is.
If all your house's faucets are the 1-handle joystick type with a thermostatic anti-scald feature, then you can crank the hot water heater temperature up to the max without worrying about scalding. This is a good idea anyway, given the several types of bacteria that can breed. and fester inside a water heater not kept hot enough (140F). A hotterhot water tank contains more energy, and when you meter it out for your target temperature, that means it lasts longer.
But don't get clever and think "ho ho, I don't need a fancy valve, I can avoid scalding just by using the faucets properly / pulling my hand out". Yeah, no... if that worked, they wouldn't require anti-scald valves, would they!