My house is 12 years old and the water heater is in the attic. I've never had an attic water heater before, so it makes me nervous. I've been thinking about switching to a tankless heater, but wanted to make sure I'm not over worrying. I've heard of ground level water heaters bursting and flooding houses, so it makes me nervous the attic one could do the same and ruin my ceiling. Is this a legitimate concern?