I am certain that my gas hot water heater isn't making as much hot water as it used to because of sediment and lime buildup in the tank. The heater is 5 years old, 50 gallons. I'd like to get it cleaned of that buildup. But who do I call to get the tank cleaned? I am not handy for that kind of thing, and the tank is in a very narrow space. Do I call a plumber? An HVAC person? And what would that kind of job cost? Thanks for your advice.