Do I need to Flush out or drain my water heater?

Water heater drawingMany of my home inspection customers ask about the need to flush out their water heater due to the hard water we have here in the Phoenix area.

Customers sometimes report white particles that clog plumbing fixtures. They may be bits of calcium carbonate scale coming from your water heater. The scaling may be worsened because water heater thermostat is too high. If the particles are calcium carbonate, you probably need to flush your water heater. Many manufacturers recommend periodic flushing of water heaters to remove sediment that can build up. The sediment can cause discoloration of the water and can make the water heater less efficient. Be sure to follow the manufacturer’s owners guide for your hot water heater.

So the question is “Should you drain and flush your water heater?”

My answer is maybe. If your water heater is less than a year old and you wish to drain it then fine.
If the unit is two years old or more you may wish to reconsider.
You see sometimes draining a unit that has not been drained for a long time will break up the deposits in the tank and these deposits can cause more problems.

To drain and flush the water heater, do the following:

Follow the manufacture’s instructions if they are available, most can be found online.

TURN OFF THE GAS OR ELECTRIC to the water heater.

    Failure to do this can cause damage to the unit and possibly injury to anyone near the unit.

Connect a hose to the bib on the bottom of the unit and run the hose to a safe place outside. (don’t open the valve yet.
Turn off the water to the unit (typically at the valve located above the unit) and open a hot water faucet in your home and then open the bib at the bottom of the water tank.

This will allow all of the water in the water heater to drain. Then before you close the drain, turn on the water, this will allow any sediment that has settled on the bottom of the tank to be flushed out through the hose, thereby reducing the sediment flushed to your faucets.

now close the hose bib and let the tank fill until water comes out of the hot water fixture you opened to drain the unit. This allows most of the trapped air to escape through a single fixture and reduces the amount of air trapped in the other fixtures. This also confirms the tank is full before you proceed with the next step.

After the water heater is full, turn the gas or electric back on to the unit. If it is a gas unit you may need to re-light the pilot light.

Now go open the other hot water fixtures in the home and allow the air to escape.
I suggest that after a few days you remove the tip of your faucets and clean the aerator (the little screen at the end of most faucets) don’t be surprised to find some particles in there that got flushed out of the tank.

If you have a gas water heater and you hear popping sounds coming from the unit, this may be an indication that the unit needs to be flushed, do not be surprised if the popping sounds do not go away after you flush the tank.

If the unit has not been flushed for years you should know that the deposits that break loos during the flushing process may clog the unit or your faucets a few days after flushing. This is why I answered maybe at the beginning of this post. It really sucks to drain your water heater only to have it fail or clog a week later.

If you want more information about home inspections, what to look for in an inspector, common issues found during a home inspection or how to get your home ready for a home inspection click the links.

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  1. flush out their water heater is necessary in homes…its a good facilities for our home…Thanks for this informative article…

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