Some shower fixtures have a hot water adjustment on them so that you can set the water temp lower. take off the handle and look at the assembly. Do you see a small plastic sleeve that can be turned? If so turn it to the left and see if that changes the water temp.
No, the shower has both hot and cold water available.
Replace the shower valve.
Only hot water may be coming out of the shower because there could be an issue with the water heater, such as a malfunction or a setting that needs adjustment. It is recommended to check the water heater and its settings to ensure that both hot and cold water are being properly supplied to the shower.
When you take a shower, you're mixing a combination of hot and cold water to make a comfortable temperature for the shower water. A toilet draws only off the cold water system. In older or poorly designed plumbing systems, when you flush the toilet, the cold water is pulled by toilet, so the water coming through the shower is only drawing from the hot water tank.
The hot water in the shower does not last long because the water heater has a limited capacity to heat and store hot water, which can be quickly used up when taking a shower.
Bad /defective divertor
There could be several reasons why the hot water in your shower only lasts for about four minutes. It could be due to a small water heater capacity, a malfunctioning heating element in the water heater, or issues with the shower fixture itself. It's best to have a professional plumber inspect the system to identify and address the specific cause.
Did you remove the shower head and check for a flow restrictor or mineral deposits blocking the orifices
Do you have hot water at other fixtures in the house? If not you have a water heater problem. If yes the Shower valve needs to be rebuilt if it is a bressure balanced faucet the concentration should be on the pressure balancing spool area of the faucet.
The shower water may not be hot enough due to issues with the water heater, such as a malfunction or setting adjustment.
Because the water in the pipes is at room temperature. You must push all that cool water out with the hot water before the hot water reaches your faucet.
Yes i would say, i can have a 30 min shower of hot water, it also depends on the size of your hot water tank.