I’m about to close on a house next week and the water heater is located in the attic. It’s 17 years old and I’m nervous about the damage it will cause if it ever leaked. I want to replace it with a tankless as soon as possible before I move in.
Is there anything I can do to prevent it from leaking? If the gas is turned off while utilities get switched to my name will that cause it to leak? Is it a good idea to turn the water heater off as soon as I close on the house?
First of all even a tankless WH can leak, so in a vulnerable spot like an attic, you should have a drain pan under it to catch any leaks and route the water to a drain. Same with a standard tank WH. In fact, many AHJs require such for tank WHs at least.
If that's not present, you should shut off the water to the tank and drain it. That will ensure that it won't leak until you get it replaced.
The house is not your responsibility until you close, so for now it's the current owners problem. You could request a walk-through a few hours before the closing, and such things are not uncommon. You should also be sure you get possession immediately upon closing so that you can go right to the properly afterwards and make sure it's all secure.
I think if I was worried, I'd just shut it off and drain it. Turn the temperature dial all the way to "off" and close the gas valve, and it's off.
Then just hook up a garden hose and drain it. You won't get everything out if you run the hose out an attic window - the hose has to stay below the level of the drain spout. So you might have to run the hose across the floor, down the steps, then either into a 2nd floor sink or tub drain, or out a window, you get the idea.
