If your hot showers are cooling off too quickly or your water heater sounds like it’s boiling gravel, it’s time to give your system some attention. Most homeowners should flush their water heater once a year, though in some San Francisco homes, that might need to happen more often.
Our city’s mix of soft and mineral-rich water can lead to sediment buildup that clogs, corrodes, and shortens your heater’s lifespan. Routine maintenance keeps your water heater system clean, efficient, and ready to deliver reliable hot water when you need it most.
In this guide, we’ll explain how often you should flush your water heater, what signs to watch for, and why professional maintenance can make all the difference.
At a Glance: How Often to Flush Your Water Heater
- Flush traditional tanks once per year, or every six months if you have hard water.
- Tankless units need descaling every 12–18 months.
- Regular flushing prevents sediment buildup, corrosion, and poor efficiency.
Why Water Heater Flushing Is So Important
Think of your water heater as a quiet workhorse: it heats water every day, often for years, without complaint. But over time, minerals and debris settle at the bottom of the tank. That sediment layer forces your heater to work harder, wasting energy and wearing down components.
In San Francisco, even slightly mineral-heavy water can speed up this buildup. When left unchecked, sediment acts like a thermal barrier, creating hot spots that can crack the tank or cause leaks. Regular flushing clears the buildup, keeps your heater running efficiently, and helps prevent expensive surprises down the line.
How Often Should You Flush Your Water Heater?
For Traditional Tank Water Heaters
Most households do best with a yearly flush, especially if your water heater is in constant use. Homes in areas like Daly City, South San Francisco, or parts of the Peninsula may need more frequent service (about every six months) due to higher mineral content in the local water supply.
For Tankless Water Heaters
Tankless systems are more energy-efficient, but they’re not immune to mineral buildup. Instead of a flush, these units need professional descaling. That process removes calcium and lime deposits from inside the heat exchanger and water lines, keeping water flow and temperature consistent. Most tankless systems should be descaled once every 12 to 18 months.
Signs Your Water Heater Needs Flushing
Unusual Sounds
Rumbling, popping, or cracking noises usually mean sediment has hardened at the bottom of the tank. Those bubbles of steam fighting their way through debris are your system’s way of begging for a flush.
Rusty or Cloudy Water
Discolored water points to corrosion or heavy sediment. If you notice reddish or murky water when you first turn on the tap, the tank may already be deteriorating from the inside.
Less Hot Water
When sediment takes up space in your tank, you’re left with less room for actual hot water. If showers are shorter or temperatures fluctuate, it’s likely time for maintenance.
Higher Energy Bills
A water heater struggling to push through buildup consumes more power or gas to heat the same amount of water. Rising utility bills are a classic symptom of an inefficient system.
DIY vs. Professional Water Heater Flushing
Keeping sediment buildup under control can mean the difference between a reliable appliance and one that fails early, which brings us to the question: should you flush it yourself or call in a pro?
Can You Flush It Yourself?
It’s possible, but tricky. Flushing a water heater requires turning off power or gas, draining hot water safely, and managing potential clogs at the drain valve. One mistake could cause burns or leaks. Homeowners who are comfortable with basic plumbing maintenance might attempt it, but most prefer to leave it to the experts.
Why Hire a Professional
Professional plumbers, like the team at George Salet Plumbing, go beyond a simple drain-and-fill. They:
- Fully inspect your tank for corrosion, leaks, and faulty valves
- Use high-pressure tools to remove sediment efficiently
- Check your anode rod (the metal rod that protects against rust)
- Make sure that all safety and efficiency systems are working properly
Hiring a pro saves time and guarantees your water heater is cleaned, calibrated, and ready for another year of service.
How Regular Flushing Saves You Money
Annual flushing is one of the simplest, most cost-effective ways to extend your water heater’s life. You’ll notice the difference in multiple ways:
Better Efficiency
A clean tank transfers heat evenly and requires less energy to produce hot water, lowering your utility bills.
Fewer Repairs
Removing sediment prevents overheating, valve damage, and pressure buildup—three of the most common repair calls plumbers receive.
Longer Lifespan
Regular maintenance can easily add several years to your unit’s service life, delaying the need for a costly replacement.
Consistent Comfort
No more fluctuating temperatures or running out of hot water mid-shower—routine care keeps your system reliable year-round.
Preventing Future Sediment Buildup
Even between flushes, there are steps you can take to keep your system running clean:
- Install a water softener to filter minerals before they reach your heater.
- Lower your thermostat to around 120°F to slow mineral crystallization.
- Schedule annual inspections so a plumber can spot small issues early.
A few small habits now can mean fewer surprises later, and a longer-lasting water heater overall.
Keep Your Hot Water Flowing Smoothly
Hot water is something most of us don’t think about until it’s gone, but a quick annual flush is all it takes to avoid that cold-shower surprise. For San Francisco homeowners, where mineral levels vary from neighborhood to neighborhood, expert installation, trusted repairs, and regular maintenance are the key to reliable comfort and lower utility costs.
Schedule Water Heater Service in San Francisco
If it’s been more than a year since your last flush, or you’re hearing strange noises from your tank, it’s time to call the experts. George Salet Plumbing provides trusted, professional water heater service throughout the Bay Area. We’ll inspect, flush, and fine-tune your system so you can enjoy consistent hot water with peace of mind.
Contact our expert team online or dial (415) 234-0733 to schedule your water heater maintenance today.