Flushing a water heater removes sediment buildup, which extends the tank's lifespan and prevents popping or knocking noises. To do it, turn off the power and the cold water supply. Attach a garden hose to the bottom drain valve and run it downhill to a safe drain. Open a hot water faucet to break the vacuum, then open the drain valve completely to empty the tank.
Yes, you can absolutely flush your hot water heater yourself! It is a manageable DIY project that takes about 1 to 2 hours and helps remove sediment buildup, which ultimately extends the lifespan of your tank.
To remove sediment from a water heater, drain the tank and flush it. Turn off the power/gas and the cold water supply. Connect a hose to the drain valve, open a hot water faucet, and open the drain valve. Once empty, flush with cold water, refill the tank completely, and restore power.
Yes, you should flush your water heater. Experts typically recommend flushing it once a year to clear out sediment and mineral buildup, which improves heating efficiency, lowers energy bills, and extends the tank's lifespan. However, if your tank is over 4–5 years old and has never been flushed, you generally shouldn't start.
With the pressure relief valve open, open the drain valve and allow the tank to drain completely. Completely draining the tank ensures that you've removed all of the sediment possible.
In short, draining removes water. Flushing removes sediment, and that makes all the difference.
If the gas burner or electric heating elements come on during the flushing process, the water heater can be damaged, requiring repair or replacement. Some manufacturers will recommend turning the gas off completely during this process, others may recommend setting the gas valve to the “pilot” or “vacation” setting.
If a standard showerhead is fitted, it will use around an extra half a gallon each minute, accounting for a 25-gallon emittance every 10 minutes, or 50 gallons throughout a 20-minute shower. *1 gallon = 4.54 litres.
Water main flushing is the process of cleaning the interior of water mains and removing any accumulated sediment by sending a rapid flow of water through the mains. This rapid flow disrupts any sediment that may accumulate in the main over time, allowing us to filter and remove it.
You can tell your hot water heater is full of sediment by listening for unusual popping or rumbling sounds, noticing a drop in hot water volume, or experiencing fluctuating water temperatures.
A water heater flush tool is designed to break up and remove hardened sediment, mineral buildup, and clogs from the bottom of water heater tanks. By agitating the tank, these tools restore water pressure, improve heating efficiency, and prevent premature tank failure without messy manual flushing.
Flushing your water heater too frequently (more than once or twice a year) wastes time and water. Worse, if you flush an older, unmaintained tank, you risk dislodging sediment that is sealing tiny pinhole leaks, causing the tank to leak or breaking brittle drain valves.
How to Flush a Tank Water Heater
Flushing a 40-gallon water heater typically takes 30 minutes to 1.5 hours from start to finish. Draining the tank takes about 10–20 minutes, while the actual flushing (agitating and rinsing out sediment) and refilling the tank take up the rest of the time.
Draining a water heater properly should not damage the unit. Damage typically occurs when safety steps are skipped, such as leaving the power or gas on, not opening a hot water faucet to relieve pressure, or using a damaged hose.
You should never flush an older water heater (typically 5 to 10+ years old) that has never been flushed before. Accumulated sediment in old tanks can seal small rust holes or cracks; flushing this debris away can dislodge the seal and cause immediate leaks.
It takes about 30 minutes to 60 minutes to flush the water mains on each street.
No, it is highly recommended that you do not flush a 20-year-old water heater.
The best way to flush depends entirely on the context. Here are instructions for common scenarios:
A water heater needs to be flushed periodically to avoid: A premature breakdown. Hot water shortage problems. Noise from the water heater.
Yes, a 10-year-old water heater is considered old. Traditional tank-style water heaters generally have an average lifespan of 8 to 12 years, meaning your unit is nearing or has reached the end of its reliable lifespan.
Flushing can be an important maintenance technique to remove stagnant water, restore disinfectant residual, remove loose deposits, and scour pipe surfaces. Flushing can reduce water age and address water quality complaints.
A 10-minute shower typically uses 20 to 25 gallons of hot water. Because showers are usually mixed with cold and hot water to reach a comfortable temperature, the actual volume of hot water drawn from your heater will usually be slightly less, while a low-flow showerhead can reduce this amount by up to 50%.