Hot Water Storage Tank Maintenance

Domestic Hot Water Storage Tank leaks are an all too common problem in multifamily residential buildings. Often the tanks are located in mechanical equipment rooms that are difficult to access in a cellar or on a roof level. The storage tanks may be stand alone units, or combined as part of the Hot Water Heater. The storage tanks eventually develop leaks which will require costly and sometimes difficult replacement which may disrupt Hot Water Service while they are implemented.

While these tanks seem like simple components of a building’s plumbing system, “it’s just a big tub that holds water right?”, as with anything else it requires preventative maintenance. Practicing this preventative maintenance will prolong the life of this equipment, and allow for more deliberate planning of their eventual replacement as opposed to emergency repairs that may yield sub-optimal replacement configurations out of necessity.

Tanks should be flushed periodically, and attention should be paid to the color of the water being discharged. This will alert operators of any potential accelerated corrosion issues and allow sediment to be removed. A regular inspection program should be incorporated into the flushing process. Manufacturer recommendations vary but tanks should be flushed every six months and cleaned annually. When was the last time your hot water tank was flushed?

Perhaps the most overlooked item is the maintenance of sacrificial anodes. Hot water heaters with storage capacity and tanks will come equipped with anode rods, usually made of magnesium or zinc. These critical components cathodically protect the tank from corrosion. They are designed to waste away instead of the tank and lining materials. These rods should be removed and inspected when the tank is flushed in order to check if they need to be replaced. Rods that are wasted away will no longer offer any protection and the interior surfaces of the tanks and fitting will begin to corrode. Aggressive water qualities may require more frequent inspection and replacement of anodes.

Following these tips and investing in the preventative maintenance of your equipment will result in a longer useful life for your equipment, better quality water supply to residents and reduce the interval or complexity of costly repairs.