Turning on the hot water and having rusty water come streaming out can look like a scene from a horror movie. But the real scare is the potential plumbing failures and flooding that can happen if you leave the problem undiagnosed. Does the rust water only come out when you turn the hot water handle? The problem is likely inside your home's hot water heater.
There are a couple of potential reasons that a hot water heater can send rusty water out to your faucets. You can undergo the fixes yourself with a bit of time and effort or you can call in a plumbing and heating repair technician to do the job.
Tank Needs Flushed
Water heaters need to be flushed once or twice a year to prevent sediment buildup in the bottom of the tank, which can start to corrode the tank. Flushing simply requires that you empty the tank out and refill the tank with fresh water.
Make sure you turn off both the electrical supply to the tank and the tank's cold water supply valve before you begin the flushing. Don't know where the cold water supply valve is located? Look at your owner's manual for assistance. While you are in the manual, also locate the drain valve, which comes next.
Hook one end of the hose up to the drain valve and place the other end into the drainpipe in your basement or out a window. Make sure the water going out the window isn't flooding the area around your home's foundation or you could end up with water damage. Note that the water is also going to be quite hot so you don't want to aim it where anyone or anything could be in danger of being splashed.
Place a large bucket under the pressure release valve and open the valve. Wait for all of the water to drain out from that route before opening the drain valve. Now wait until water stops running out of the hose, which signals that the tank is completely emptied.
Turn off the drain valve and pressure release valve. Remove the hose and the bucket, disposing of the water in the bucket down the drainpipe or into your yard. Go around the house and turn on every single hot water faucet you have to minimize pressurization issues once you turn the tank back on.
Turn the cold water supply valve and electricity both back on for the unit. Wait until the hot water has started to run out of every faucet you turned on before switching the faucets back off.
Need New Anode Rod
If you are diligent about flushing your tank but are still experiencing rusty water, your tank might need a new anode rod. The anode rod is a metallic bar that hangs down in your tank's water and chemically attracts most minerals in the water that could cling to the tank and cause corrosion. Mineral buildup over time will render the anode rod less efficient before making it fail to work at all.
You can check on the anode rode by partially draining the tank -- use the flushing procedure then interrupting the draining by closing the drain valve – and then unscrewing the rod's fastener on the outside of the tank. The rod should then pull out for easy inspection.
If the rod looks dirty or damaged, take the rod to the hardware store to find a new replacement rod. If the rod looks fine and your tank was recently cleaned, call in a plumber (such as one from Bob's Plumbing & Heating) or water heater tech to diagnose the source of your rusty water.