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Water Heater Never Gets the Water Hot

Last Updated on Tuesday, 11 May 2010 20:31 Friday, 07 May 2010 17:00

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Common Plumbing Problems - Water Heaters

Here are the most common things to check before you call a plumber. If you recently changed shower heads, make sure you use the 2.5gal/min heads. Other shower heads may release as much as 10 gal/min. In 4 minutes, all your hot water will be used. If you did not replace the shower head, and this problem has just started, it is possible that the divider inside the head is defective and is letting the water flow at a higher rate. If that is the case you should replace the shower head.

To determine if the water heater is defective make sure there are no appliances using hot water for at least a half hour to make sure the water is completely heated. Plug the bath tub and turn the faucet all the way to hot. When the water starts turning cold, turn the water off. If your bathtub is about 1/3 full, (standard tub size about 120 gallons) your water heater is more than likely doing its job and there are no problems with the heater. If you do not get a full 1/3 tub full of water, it is possible that the dip tube inside the water tank is defective and mixing cold water with hot water. The dip tube is a pipe that extends to the bottom 1/3 of the tank and where cold water enters. Hot water is siphoned off the top of the tank (hot water rises). If a bad dip tube is the problem you can simply have plumber replace that.

Verify that there are no sediments at the bottom of the tank. If you are in an area with hard water, it is possible that sediments built up at the bottom of the tank. This prevents the heater from coming in contact with the water and can dramatically reduce the transfer of heat from the heater element to the water. If this is the case, the element may need to be replaced or cleaned. About the only time you need to replace the water heater is when it leaks.