Hot Water sputters

[Bob Vavricka]

My son had a new hot water heater put in over a month ago and when I was visiting he showed me that when you turn on the hot water on faucets connected to that hot water heater it sputters like when you have air in a line. I would think any air in the line from replacement would be long gone. It is worst when running the hot water wide open. When standing by the hot water heater while water is running, I hear a bumping sound similar to what I think I would hear from a hot water heater with a lot of lime in the bottom, but it is a new heater. Any plumbers or others that have experienced this?

[Frank Pratt]

Is he on a well? Some well water will degass when heated.

[Bob Vavricka]

No, He is on City water.

[Lee Schierer]

How hot is the water coming out of the faucet? He could have a bad thermostat in the water heater and it is getting near the boiling point.

[George Yetka]

If temperature went that wild the relief should open. Not to say that isnt what it is.

Perhaps a break in the supply to the house somewhere? Does he get any sputtering on the CW

I get this from time to time on well water if the pump doesn't come on for some reason( Brand new pumptrol but it has left me without water 4 times)

[Bob Vavricka]

Only on the hot water side, not on cold water.

[Larry Frank]

I think you have air in the hot water heater.

Note...I googled the symptoms and this came up a number of times.

[Bill Dufour]

have him release the vent on top of the water heater for a few seconds to see if any air comes out. If air vents keep it open until it stops.

[George Yetka]

This air would have gone if its an ongoing thing. Water is supplied to bottom of tank and taken off the top so any air in the tank would have left from the faucet eventually. If It is continuing over days to have this issue its not just from the first fill.