Hot water heater valve

You're right to be concerned. The valve could just as easily stick open.

The complete control is indeed replaceable, but on a 6yr old heater not cost-effective IMHO. The control alone will cost you close to $100. That's a good fraction of a new heater cost. Gas heaters have an average life of 10 yrs.

Jim

Yes.

Probably. Check prices and you will find it much less than a new heater and it can last you another 10 y ears or so.

Less likely but anything is possible. Replace it and have peace of mind.

Why do you want to heat hot water?

There's a good chance it will happen again, and with more frequency. There's also a slight chance that a little piece of dirt got in there, and you dislodged it. This happens once in a while, especially when there's no 'drip leg' installed on the gas piping. Call a repairman and ask the price to repair or replace your water heater. The life expectancy of a water heater depends a lot on the water in your area and capacity vs. demand. You might want to wait to see if it happens again before making a final decision. If you decide to replace the whole thing, consider an energy efficient model that uses a lot less gas.

Not a factor with a water heater. If your house heater is not being used for days or months, there is no reason to keep a pilot light burning. If you are not using the oven for hours or day, there is no reason to keep a pilot light burning. Hot water, OTOH, is kept hot and ready to go at all times. The pilot light will give off some heat to maintain temperature between uses, thus, very little if any real loss. If not for the pilot, the burner would cycle on and off more frequently.

Thanks for the link. Appreciate it.