water heaters

just wanted to mention this, that if a water heater is old or has not been emptied for a long time, it can explode. I am having someone come out to check mine, I'm worried its old, this place is 20 odd yrs old, and since I will be going away for a few days next month, thought it would be a good idea. I don't want it to explode hot water when I or my cats walk by it(its in a closet off the kitchen).
I don't know if they have to be emptied, or what, but I know there is something they have to have done every so often...does anyone know?

Do you have a gas or electric water heater? I believe only a gas water heater can actually explode. I just had to replace mine 2 weeks ago. (It was electric.) It was 27 years old...the original one since the house was built. Mine just began leaking out of the bottom, meaning that something cracked on the inside. It seeped for a couple of days until the new one could be installed. It does have to be emptied in order to be cleaned.

Think Deb is right - water can't expand by itself with enough pressure to burst....when I lived in the UK though we had a big freeze and it cut the power so the water heaters were not heating but freezing - they can burst then alright.....as I found to my cost. Can laugh now - better to get their checks when they are due though.....even floods from heaters can be costly.