New water heater installed old one was a 30 gal new one is 40 gal. when I run the hot and cold it fades between the hot and cold. I lost some water pressure but not a lot. Can anyone suggest what can be causing this?

Hi Bryan...

Could be that the DIP TUBE got disturbed or was melted during the installation. This could be something you did... could also be a manufacturer defect... ;)

The dip tube usually delivers cold water to the bottom of the water heater where it can be heated and will rise up to the hot water outlet of the water heater to be delivered to the house. If the dip tube is broken/cracked/defective, etc. then cold water simply flows directly over to the hot water outlet without being directed to the bottom of the water heater to be properly heated thereby creating a cycling between hot and cold water at the hot water outlet much like you describe.

To check the dip tube, you would need to remove the cold water nipple and then use a pair of needlenose pliers to reach into the inlet and pull the dip tube out to be inspected.

See images below for more info.

Questions? Let me know, OK?

Mark

Just throwing it out there, did you accidentally invert the inlet and outlet when installing the new heater, that could be your problem too.

Hey, you never know, do you? A reasonable answer, for sure!

Mark

Hey Mark

Is dip tube flexible to the point that it can be removed from heater?

Chuck

Hi Chuck...

Yeah, in most cases the dip tube can be bent pretty far to facilitate removal... :)