My family is complaining that the shower is going cold easily (faster than normal) and they are having to turn the hot water on more to keep the shower hot. This is happening even with the first shower of the day so it's not the water getting low. I don't notice it so much, but I take pretty short showers compare to the kids and my husband. I read in another post about how something could be the shower cartride valve? Is there some way of testing to see if it's that or an issue with the hot water heater itself?
My husband did flush the hot water heater to make sure there wasn't sediment in the shower, but the problem still persists.