Where the sediment comes from
Fullerton's water is a blend of local groundwater and imported supply, and it carries dissolved calcium and magnesium. When that water is heated, some of those minerals come out of solution and drop to the bottom of the tank as a gritty, chalky layer.
On a gas tank, the burner sits right under that layer. Water trapped beneath the sediment boils in small pockets, which is the popping and rumbling people hear. The burner also has to push heat through the crust, so the tank takes longer to recover and the bottom runs hotter than it should.
Signs of heavy sediment
- Popping, crackling or rumbling while the burner or elements run
- Hot water running out sooner than it used to
- Grit or white flakes in faucet aerators
- A drain valve that clogs or runs cloudy when opened
- On electric tanks, a lower element that keeps failing
How sediment builds over a tank's life
A general pattern, not a schedule. How fast it happens depends on water use and temperature.
- Early years
- A thin layer forms. Regular flushing removes most of it easily.
- Middle years
- If never flushed, the layer thickens and hardens. Noise starts, recovery slows.
- Later years
- Hardened scale resists flushing and can clog the drain valve. The anode rod is often spent.
- End of life
- Overheated tank bottom and corrosion lead to leaks. Replacement is the only fix.
How a flush is usually done
Many homeowners hire this out. If you do it yourself, follow your heater's manual and stop if anything does not behave as described.
- Turn the heater off.Gas control to Pilot or Off, or breaker off for electric. Never let electric elements run without water around them.
- Let it cool.Tank water can be scalding. Waiting reduces the risk of burns from the discharge.
- Close the cold supply and attach a hose.Run a garden hose from the drain valve to a safe drain or outdoors where hot water will not harm anyone.
- Open a hot tap and the drain valve.This lets air in so the tank drains. Watch for the water to run from cloudy to clear.
- Refill fully before restarting.Close the drain, open the cold supply, and run a hot tap until air stops spitting before turning the heater back on.
Worth asking a plumber
- Is this tank a good candidate for flushing, or is it too far gone?
- Should the anode rod be checked while you are here?
- Would a different temperature setting reduce sediment and scald risk?
- Is water treatment worth considering for this house?
Common questions
- How often should a tank be flushed in Fullerton?
- Follow your heater's manual. Because the water is hard, many households benefit from regular flushing rather than waiting for noise to start.
- Does popping mean the tank is about to burst?
- Not by itself. It usually means sediment. But loud, persistent rumbling on an older tank is a reason to have it inspected.
- Does sediment affect electric heaters too?
- Yes. It can bury the lower element, which then overheats and fails. Repeated lower-element failures are a common sign.
General information for Fullerton, not a quote or professional advice. In an emergency, call 911.