Q. You mentioned to me that my 24 year old water heater is a candidate for replacement based on age and I agree. What is your opinion on the tankless systems that seem to be common now? Also, the water heater is currently located so far from the bathrooms that we wait and wait for the hot water to arrive at the sinks and showers.
A. I've seen many water heaters as old as yours. Water heaters that are on municipal water supplies, such as yours, tend to last a good long time as the water is not acidic and doesn't have a lot of particulate junk in it to coat the tank bottoms causing them to burn out over time. As long as your water heater is not leaking it's still a good soldier. But at its age, planning for replacement is a good idea. Water heater failures can be an abrupt surprise and always seem to occur at inopportune times such as on a weekend or when you’re out of town and you come home to a minor disaster.
The reason you are interested in the tankless water heaters is most probably due to the wait you endure for hot water. The average American family runs 26-29 gallons of fresh water per day down the drain waiting for hot water to arrive from the water heater tank. That can add up to 10,000 gallons a year down the drain that you didn't get to splash around in.
The best types are gas tankless water heaters that many people see while traveling overseas in Europe or Japan. But keep in mind, these models tend to be point-of-use water heaters and the plumbing set up in your home is rigged for remote water heating that is directed through a series of pipes to each individual point of use.
Electric tankless water heaters seem to be cost competitive with the old fashioned tank type until you factor in the rewiring that they require that can force you to even increase the electric power capacity to the house. Installation can run into the thousands.
Remember gas tankless water heaters may be tankless but they aren't ventless-- so they must be vented to the exterior. A model that I saw recently marketed in this country is by Bosch. They brag about their product in how much money they can save you annually but in the literature they sent me there was no mention of how much their product cost to buy and install. You can call them at 1-800-642-3199 and ask them yourself. They have dealers locally if you get serious but you need to examine your requirements more carefully before you make a decision.
The type of tankless water heaters that are both an "on-demand" and "point-of-use" type water heaters used in this country are electric, mount under sinks and consume quite a bit of juice when in use. Again, it becomes a wiring issue as well as a plumbing job.
There are other devices available that you actually push a button just prior to using hot water and it turns on a pump that pushes the cold water resting in the hot water line back to the hot water tank, then the pump shuts off and the line is immediately refilled with hot water-- they cost about $400 and that is, I believe, cost competitive with a tankless water heater-- electrical usage and installation aside.
The system is called the Metlund Hot Water D'MAND System and was developed principally as a convenience product to eliminate the long wait for hot water. It just happens to save money over time through the elimination of water wastage. It's not as complicated as it sounds and suffice it to say, it's ingenious.
The independent studies I've seen show an annual dollar savings with its use of $179.00 in the test areas out West. It'll be less around here--about $50. a year if you are on both municipal water and sewer-- but what you want is the convenience. Some Home Depots carry them and I'm sure they could order one in for you if you asked. You can find out more about them at www.gothotwater.com
Short of tearing your whole hot water supply system apart and redesigning it, something like this might fill the bill. It doesn't make sense to spend thousands of dollars to save a few. Thrift is part of conservation too.