Water Heater Repair
Troubleshoot cold showers, leaks, rumbling and pilot or element failures.
Homeowner guide
Water Heater Flush and Maintenance in Commerce City, CO
A tank water heater needs a little attention once a year. Flushing sediment, testing the relief valve and checking the anode rod are the three jobs that matter most.
By the Mile High Express Plumbing team · published
Why maintenance matters
Sediment collects at the bottom of the tank and insulates the water from the burner or element. The heater then burns more energy, pops and rumbles, and wears out sooner. Skipping maintenance is a frequent cause of early failure.
The tasks below take about an hour once a year. If you have never flushed your heater, do it carefully and be ready to stop if the drain valve clogs.
How to flush the tank
Cut power, or set a gas control to pilot, and close the cold supply valve. Connect a garden hose to the drain valve, route it to a floor drain or outside, and open a hot tap in the house so air can enter. Then open the drain valve.
Let the tank drain fully. Briefly open the cold supply to stir the remaining sediment and drain again until the water runs clear. Close the drain, refill the tank with the hot faucet open and restore power or gas only after water flows steadily.
Test the relief valve
Place a bucket under the relief pipe, and lift the lever briefly. Water should flow, then stop when released. If it keeps dripping or does not flow, replace the valve. Never plug it.
A relief valve that never seems to move can be stuck. If you cannot get it to work, call a plumber. It is a safety device.
Check the anode rod
The anode rod corrodes in place of the tank steel. Over the years it wears away, and then the tank begins to rust. Many plumbers suggest checking it every three to five years, and sooner in harder water.
Pull the rod when you flush. If more than a few inches of core wire show, replace it. A new rod costs little compared with a new heater.
Annual heater upkeep list
Four jobs that add up to about an hour.
| Job | Frequency | What it guards against |
|---|---|---|
| Drain and flush the tank | Each year | Sediment buildup and rumbling |
| Lift the relief valve lever | Each year | Dangerous pressure |
| Pull and inspect the anode rod | Every three to five years | Rust through the tank |
| Look for drips and corrosion | At every flush | Failures that arrive without warning |
Temperature and settings
A setting of about 120 degrees is common, and it reduces scale and scald risk. Higher settings are sometimes needed for dishwashers or large households. Ask a plumber if you are unsure.
If you will be away for a long stretch, use the vacation setting. For electric heaters, turn off the breaker for extended absences.
Hard water and scale
The South Adams County district reports an average of 7 grains per gallon of hardness. Moderately hard water leaves scale, so a yearly flush matters. A softener reduces buildup if scale is heavy.
Sediment sounds like popping or rumbling when the burner heats. If you hear it, flush now.
Signs it needs more than a flush
Rusty hot water, a metallic smell, water around the base, a heater over ten years old or a pilot that will not stay lit all point to bigger problems. A repair visit can diagnose them.
If the drain valve is plastic and clogs, do not force it. A plumber can replace it with a brass valve.
When to replace
If the heater is old, rusted or leaking from the tank, replacement is usually the better value. A replacement also lets you choose a different size or a tankless unit.
Write the install date on the tank with a marker so you always know its age.
Gas and electric differences
On a gas heater, check the flame and the flue. The burner flame should be mostly blue and steady. A yellow or flickering flame, soot or a draft that blows out the pilot needs a technician. Never block the combustion air or store paint and solvents near the heater.
On an electric heater, the elements and thermostats can fail with sediment. If the tank is sandy at the bottom, the lower element can burn out. A technician can test the elements with a meter, and a flush may restore normal heating.
Insulation, pipes and the expansion tank
Foam sleeves on the first few feet of hot and cold pipe cut standby heat loss and help in cold weather. An insulating blanket on an older tank can help if the manufacturer allows it. Never cover the controls or the vent.
If your house has a check valve or a pressure reducing valve, an expansion tank absorbs the pressure rise as water heats. Press the air valve on the tank. Water coming out means the diaphragm failed.
Keeping a maintenance log
Write the flush date, the anode inspection and the relief valve test on a card taped near the heater. Note anything unusual, such as noises, smells or small drips. A log makes it easy for a technician to see the history.
It also tells you when the unit has reached the age at which replacement planning makes sense. Replacing a heater on your schedule is far cheaper than doing it in an emergency.
Tankless heaters need care too
A tankless unit has no tank to flush, but it does have a heat exchanger that collects scale. Manufacturers often recommend descaling once a year in harder water, using a pump and a descaling solution that circulates through the unit.
Clean the inlet screen as well. Skipped maintenance can bring error codes and weak hot water. A tankless service visit covers the full routine.
When to call a professional
Call a professional if the drain valve will not open or drips after closing, if the anode rod will not turn, or if you smell gas. Also call if the pilot keeps going out, you see scorching or soot, or a heater over ten years old is getting noisy.
A technician has the tools to remove a stuck rod, replace a brass drain valve and test the combustion and venting on a gas unit. Some of these jobs are not safe for a beginner.
Common questions
Water heater maintenance questions
Once a year is a common recommendation, more often in hard water.
If you follow the steps and shut off power or gas first, many people do. If anything sticks, call a plumber.
Around 120 degrees is common. Check your manual and household needs.
It corrodes first, which protects the tank steel from rust.
Services that help
Water Heater Installation & Replacement
Swap out a worn tank for a unit sized for your household, fuel and space.
Tankless Water Heater Service
Descale, flush, troubleshoot or replace an on-demand water heater.
Keep reading
Water heater leaking from the bottom
Water at the base of the tank may be a fitting or a failed tank. Here is how to tell the difference and what to do first.
Hard water and softeners
Scale on fixtures and spots on glass point to minerals. Here is what your water likely contains and whether a softener helps.
Low water pressure causes
Weak flow at one tap and weak flow everywhere have different causes. A few checks narrow it down fast.
Heater overdue for service?
Phone in and tell us about the heater. A local contractor will be arranged.