Good Morning,
I,(with help) installed a new natural gas 40 gal. Water heater, removed/replaced some galvanized pipe with pex. I am now getting very little hot water (low temperature).
I turned temp setting on water heater to HOT.
I rebuilt the only single handle faucet(shower0 in the house. New gaskets and ball inside.
I check all the lines for possible cold water crossover.
With the old water heater, no problem with hot water.
Where do I go from here?
Thanks... Jim

How was the cold water inlet connected?
1. By soldering in a threaded adapter? **OR**
2. Threading in a brass nipple or heat trap? Let me know , Tom

Tom,
The cold/hot nipple were threaded in with teflon tape.. Jim

James, if you set your faucet to full hot does it have the volume like it was did? Try the drain spigot at the bottom of the tank, do you get full volume/pressure and hot water?

I get full volume (+/-) 3 gal. per min. at the faucet and a little less at the drain, I'm not positive however.

It sure sounds like a failed dip tube. If the dip tube has failed the you would have cold water directed directly into the hot resulting in a luke warm draw.
However, There's not much chance of a failed dip tube by installing nipples on the cold water inlet. That's what it sounds like to me. I just can't tie everything together. Tom

I am with Tom at this point. When you did the install did you solder the supply line directly to the top of the tank?

I am with both experts open the link below and see how the dip tube works, good luck.

John

How a water heater dip tube works and what it looks like. (http://www.masterplumber.net/electricwh/dip_tube.htm)