"The short answer is yes, but the easiest way to explain is to ask the question, 'do you feel it is reasonable to have your furnace serviced?' Most would answer yes. Well, a hot water tank burner is not so far off from a furnace. Both burn gas and have by-products of combustion, ranging from Iron Oxide to Sulfur Sodium. Everything that eats the heat exchanger in you furnace is also doing the same thing to your Hot Water Tank. One on the reasons tanks go bad so fast, is that most homeowners do not get them serviced! One of the most sensetive parts of the water tanks system is the thermocouple, which is a safety device that closes the gas valve if the pilot goes out. The life span of this little piece is about 4 years, so if you have a hard time re-lighting your pilot light, it might just be the thermo-couple!
If you do end up having to replace your water heater, make sure you ask Wes or Gill about the Rinnai On-Demand Water Heater or the Navien & Eternal On-Demand 98% Water Heaters." -Bob