I have an electric breaker panel in the bedroom closet.
On the other side of this wall is a hall closet.
I want to move my hot water heater into this closet however the contractor says that it's not good to have a water heater share a wall with a breaker box in case something happens. He recommends demo ing the closet drywall and re building it out with hardi backer to protect the breaker box.
I can find nothing in code that says this is necessary and can't really see any likely circumstance the water heater might damage the breaker box.
Question is this against code and/or is it a bad idea?
I live in California in a single family home.