We recently bought a house and the water heater (located inside the house) doesn't have a pan underneath it. I've been told it would be easiest just to have the pan added when we replace the heater, but the heater is only 3 years old, so I don't anticipate replacing it anytime soon. Is there an easy way that we can put the pan under it ourselves, or will we need a plummer to come unhook the whole thing and move it to add a pan?