Water not getting hot during day but over night

Hello, It might be that you've had one of the electic heating elements fail. In order to determine if that's the case, you'll need to be able to use a multi-meter and check both the upper and lower heating elements.

This has to be done with the electric power turned off to the water heater, so you can check for an "open" condition of the heating elements. The meter should be set to the Ohms setting or if it has a continuity setting with a buzzer, you can use that.

Once you've made sure that the power is off, by turning off the double pole breaker for the water heater, you can remove the top and bottom cover plates on the side of the unit. There are two (2) fasteners that hold them on the cabinet. Once you have them out and the cover off, you'll have to push aside the insulation to get to the connections on the elements.

I think you'll want to start by checking the top element, as that sounds like the one that has failed. The top element is the one that helps the water heater recover quickly when hot water is being consumed.

To check the element, put the test probes on each connection point of the element and if the element is bad, you will get a reading that is less than zero, since a failed or open element, will not have low resistance, but rather, with the water as a conductor in a failed condition, will have a higher resistance.

You can also check the lower element and compare the readings to confirm that the upper element has failed.

In order to replace the failed element, you will need to shut off both of the water valves cmoing into and leaving the unit. Then you'll have to drain the water heater to below the element you need to replace, and remove the failed element by removing the two wires connected to it and using a large pair of channel lock or adjustable wrench, turn the element out of the water heater tank.

Now just reverse the above to install the new element, follow the instructions provided for tightening the new element and reconnect the wires. Open up the water valves and allow the tank to fill. Once it's filled, you'll have to open up the pressure relief valve to allow the air in the tank to escape. You'll want to have a bucket handy as you'll get some water flowing out of the relief valve, as the air is forced out.

Now you can turn on the electrical breaker and allow the water heater to recover and you should be all set.

Hope you find this Very Helpful and best regards!

Open the lower compartment on the water heater, should only one screw....lookin at this picture its the blue rectangle at the bottom..after its open you will see a flat head screw, turn it clockwise to increase water temp..120 is the highest you should use. and if thats not it..one element may be out ...its an easy fix and you can buy them at lowes or home depot...elements are located under the 2 blue rectange doors on the picture