First shower of the day is cold, second is hot, what could it be? Hot water starts out cloudy, then clears up when it sits awhile. There's also a rumbling sound when hot water is turned on, not when cold only is on. These symptions all started at the same time 4 days ago, I've been in the house for 3 years. I don't have the model # in front of me, I could not find it on Rheem's website so it's probably a discontinued model. Rheem, 50 gal electric (2) 4.5kw elements (but total kw is 4.5kw). I did not see an anode rod connection
Water Heaters - Rheem - 50 GAL ELEC TALL Water Heater 6YR SC 83VR522
Answers & Comments
You may have a burned out element that is the most common cause of cold water. if you turn the hot water on only and it does not warm up then you have a burnt element. There are two elements on the heater, if you turn the power off and use a ohm meter to check between the terminals of the two heating elements if it does not move the the element is blown and you can unscrew it and take it to any hardware store and buy a new one. If it was plugged with rust water would not run out at all. The heaters come in 1500 and 2500 watt ratings and is printed on the outside of the element. to replace you will have to turn the water off and drain the tank and remove the hot water heater element.
You might try draining your hot water tank with a hose. Sometimes crud and corrosion can build up in the bottom of the tank. Excessive buildup of sediment in bottom of tank CAN is cause overheating of tank bottom and boiling of water to occur.
I would turn off the water heater (use the breaker), connect a hose to the bottom and drain it out. You may want to take a look and see what comes out of it. This is an easy thing to do and you don't have to call anyone out. Good luck!