If your hot water is lukewarm or not as hot as it used to be, it may be because your dip tube is broken. The dip tube is a plastic pipe that travels from the cold water inlet down to the bottom of the tank. The purpose of the dip tube is to deposit the cold water coming into the tank to the bottom of the tank, where it will be heated. As the water is heated it rises to the top and then exits the tank through the hot water outlet.
When there's a break or crack in the dip tube, the cold water entering the tank mixes with the hot water at the top, resulting in lukewarm water. The process of examining and changing the dip tube is relatively simple. However, if you're at all unsure about performing this task, it's in your best interest to call a professional plumber.
Dip Tube Replacement: Step-by-Step
Before performing any maintenance on your water heater, always ensure that the power is turned OFF. If you have an electric water heater go to your circuit breaker panel and turn off the breaker for your water heater. If you have a gas water heater, locate the on/off dial on your water heater and turn it to off.
Shut Off the Cold Water
Step One: Shut OFF the cold water supply to your water heater. The cold water shut-off valve is typically located just above the water heater. Close this valve before performing any maintenance or repairs. This will prevent water from entering your tank.
Drain a Few Gallons
Step Two: Attach a hose to the drain valve and drain a few gallons of water from the tank. This will clear any remaining water from the hot water pipes that is above the level of the top of the tank.
Remove the Dip Tube
Step Three: Depending on how your water heater is configured, you may need to cut the pipe between the cold water shut off valve and the water heater if you have copper tubing. If this is the case, you'll need a tubing cutter.
Tighten the tubing cutter around the pipe and rotate it around the pipe, tightening it as you go until the pipe is completely cut. Be prepared for some water to come out of the pipe once it’s removed. It won’t be a lot, but have some towels handy.
If you're water heater doesn't have copper tubing you should be able to remove water inlet pipe by unscrewing it from the water heater. It may have some corrision and be difficult to remove.
Remove the Dip Tube
Step Four: Use a pipe wrench to remove the remaining pipe from the dip tube, and then the dip tube itself. If you find your dip tube is in good condition then your water heater may be suffering from another problem and you should contact a professional to help you troubleshoot.
If the problem is the dip tube, you'll often find that it is heavily corroded and missing large chunks, or it may even be broken.
Install the New Dip Tube
Step Five: Wrap the threads of your new dip tube with Teflon tape. Insert the dip tube into the water heater and replace the piping.
Turn On the Cold Water
Open the cold water supply to the water heater to refill the hot water tank. Once the tank has filled, turn the power back on at the circuit breaker (electric) or the gas control valve (gas).