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Frequently Asked Questions

Q. "I read somewhere that turning your water heater down to 120°F can help you save energy and money on your utility bill. Is this true?
A. In a word, yes. However, it is important to bear in mind that many of the people and websites promoting this tactic are not plumbers (who understand how hot water systems work) or doctors (who understand how germs work). Setting your water heater at 120°F may help you save money or energy, but that temperature also creates a prime breeding ground for all kinds of bacteria. We strongly recommend keeping your tank-style water heater set at 140°F or higher to ensure that disease-causing bacteria like legionella (which causes Legionnaires' disease) cannot grow in the tank or in the pipes as the hot water circulates. If you are concerned about the risk of scalding due to the higher temperature, we suggest installing thermostatic mixing valves either at the hot water tank or at key delivery points in your plumbing system to help mitigate the risk of burns.

Q. "Why would anyone need an expansion tank?"
A. Water is incompressible. Unlike air, it's impossible to squeeze any quantity of water into a smaller volume. Where that matters is in "closed" water systems such as a water heater with a check valve (pressure regulator and the like) ahead of the heater. When the water gets heated it expands and that extra volume has to go someplace. Without an expansion tank the pressure could rise to a dangerous level in a closed system. A diaphragm type of expansion tank (such as what we sell) is a pressure vessel that contains a flexible membrane totally separating the water from a captive volume of air. Air compresses and as the water temperature rises, creating extra pressure/space, the air in the vessel accommodates that increase. Thereby preventing a potentially dangerous pressure rise.

Q. "I have a sulfur odor smell coming from the hot water side of my faucets. A friend of mine told me that it might be caused by my water heater anode rod. Is that true and if so, if I remove the anode rod will the odors go away?"
A. Removing your anode rod will not cure the odor problem, will cause damage to the water heater tank much sooner than normal and will void your warranty. In many cases the odor is hydrogen sulfide gas. The source is sulfate reducing bacteria which is present in many water systems. That bacteria in most cases is harmless but thrives in the hot water environment. Water temperatures of about 140°F - 170°F makes for a rich growth medium. This type of anaerobic bacteria feeds off the hydrogen gas produced by magnesium anode rods. Periodic flushing of the tank with bleach solution will reduce the problem. Because there are so many factors we can not guarantee that the odor will be eliminated, but if you have no odor on the cold side of a faucet and only the warm side generally (not 100%), replacing a magnesium anode rod with one of our Aluminum/Zinc/Tin rods can help solve the problem. Some water heater manufacturers' claim that softened water causes the problems, but that is not a proven fact. Removal of the bacteria will also solve the odor problem. Sanitizing the water heater (with safe levels of bleach, etc), will eliminate the odor but only for a variable (relatively short) length of time. A trace amount of H2S gas in the water is another cause of hot water odor but removal of the anode rod will not cure that odor problem either. It is best to always have an anode rod in your glass-lined steel water heater tank.


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