Sometimes Staying out of Hot Water Isn’t an Option

Water heaters have relatively few components and are fairly easy to service. When problems do arise, a water heater can send out confusing signals. Because trouble can strike any part of your hot-water system, it helps to think in terms of its three basic elements: pipes, including all faucets and hot-water appliances; tank; and heat source.

Piping systems cause problems often blamed on the water heater. High operating costs may be traced to a dripping faucet or leaking pipe. (A faucet that drips only one drop per second wastes nearly 800 gallons of hot water per year.) In such a case, a simple, inexpensive water faucet repair will pay for itself many times over.

Long, uninsulated pipe-runs also waste hot water. When you draw water from a faucet at the end of such a run, hot water must displace water that cooled in the pipe. So, to get a quart of hot water, you must draw several gallons from the tank. Slow heat dissipation by insulating all hot water pipes.

Hot-water storage tank problems can call for a simple parts replacement or a whole new tank. If your electric heater burns up lower elements frequently, or if your gas heater rumbles, sediment may be the culprit.

An aging water system may carry sediment into the tank, or sediment may collect as flakes of calcium and lime. In electric models, sediment-covered heating elements will burn out quickly. In gas heaters, sediment accumulated in the bottom of the tank forms a barrier between the heat source and the water. Steam bubbles percolate through the sediment and cause a continuous rumbling.

To remove sediment, first drain as much water as possible from the tank. Next, with the draincock still open, turn the water on full pressure to flush the tank. Then, reduce the pressure by half and, finally, shut off the water and allow the tank to drain completely.

A fallen dip tube is a relatively uncommon problem that can bypass unheated water to the outlet pipe. The dip tube is a pipe that delivers incoming cold water to the heat source near the tank bottom. If it slips through the cold water inlet fitting and falls into the tank, cold water entering the tank is drawn through the hot-water outlet without being heated.

To replace a dip tube, disconnect the inlet pipe from the tank. Then, cut a length of one-half-inch diameter soft copper tubing long enough to reach within 12 inches of the tank bottom. Flare the pipe end so it’s slightly larger than the inside diameter of the inlet fitting. Insert the tube into the fitting and reconnect the inlet pipe. You can leave the old tube in the tank.

Late-model water heaters have a magnesium rod to coat voids in the porcelain tank lining. An anode sacrifices itself to prevent rust and prolong the tank’s life. These rods seldom cause problems, but when they do, it’s often a chemical reaction to acids and minerals that gives the water a gassy odor or taste. To correct this, unscrew the magnesium rod and replace it with an aluminum rod. Most retail plumbing outlets stock them.