I purchased a water heater about 2 years ago from Lowe's. It's always been a little picky on what temperature it needs to be on to stay lit. Recently I noticed cold water (unexpectedly and not fun!) When I light the water heater (gas by the way) it stays lit and I can hear dripping internally and sizzling when it hits (not sure exactly where it's hitting.) Then makes a click as it shuts off. I noticed when I first went to light it, that there is a white ring around the bottom of the water heater like it had leaked and dried, but since I have been down there and watching (two days) there is no wetness on the outside or around the water heater. Please help.
-Chris

When the water heater has been out for a while and the water in it is completely cold and you light the heater it will make condensation so this is probably what you are hearing because this condensation will drip down on hot metal in the heater and make the noise you hear.

Now how do you light this pilot on this heater? If it is a piezo lighter that you mash a button to make a spark you may have a problem because of that.

Below the burner you have an anti-explosion guard it is a shield filled with tiny slits and as the condensation drips down on to these slits they eventually rust and as they rust they shut the start to shut off the fresh air supply to the burner. This causes an incomplete combustion in the burner chamber and several things can happen, one is the piolet can be snuffed out and shut the unit off, second the burner can snuff itself out and this will eventually cut off the safety and close the gas valve. Also some heaters have a safety switch in the burner chamber that will open if the burner is not burning right and turn off the gas to the burner.

Some manufactures warranty against this problem but it has to be done through the company and not Lowe's.

If this information helps you please let me know.

It is lit with the Piezo igniter. It lights up just fine and stays that way for 30 seconds or so. Then I hear a click and it shuts off. When I turn the temp control know back to "off" to re-light it, I can hear a gurguling noise. Would the white ring around the bottom of the outside of the water heater tell me anything? Also I have one of the water heaters that has the "safety door" that I would need to unscrew to see if there is any rust on anything. I have absolutely no experience with water heaters other than knowing how to light them. Is it safe for me (knowing that all the gas is off) to remove the door to inspect? It's just 4 philips screws. Or would my best bet be to have someone come look at it and ask them if it's something I should go to Lowe's or to the manufacturer? It does say on the outside that it has a 9 year warranty on tank and parts. All I've had to do so far is change the thermalcupal once.

If you have changed the thermocouple once then you have already been inside the heater therefore I would tell you to try this. Turn the gas off at the gas stop at the wall or in the line leading to the heater. Now disconnect the line going to the pilot, the line going to the thermocouple and the line going to the heater. Unscrew the four screws, they may be torx screws. Pull the burner out of the heater and lay it aside. Now you need to use a shop vac, if you don't have one try to borrow one. When you look into the hole where you took the door off you can see some tiny holes or slits in the bottom of the heater, use the vac to BLOW down through the holes, trying to dislodge lint and dust that has accumulated on the underside of the holes you see. If a lot of dust comes out the vents on the side of the heater then you know you may have done some good. Vac all around the heater, inside and out, now reassemble and try it.

Either before or after you do the above, remove the vent on top of the heater and use the vac to BLOW down through the heater, Making sure the safety door is screwed in place.