Should You Flush Your Water Heater? Ask Terry Love Plumbing Forum

If you’ve ever wondered whether you should flush your water heater drain—or skip it altogether—you’re not alone. Many homeowners turn to trusted communities like the Terry Love Plumbing Forum for real-world advice on this exact question: “Flush water heater drain or not?” With sediment buildup silently shortening your unit’s lifespan and reducing efficiency, this decision matters more than you might think. Let’s unpack what experts and experienced users actually say.

Why Do People Ask “Flush Water Heater Drain or Not?”

Homeowners often hesitate because flushing seems messy, time-consuming, or unnecessary—especially if the water heater is still working fine. But as users on the Terry Love Plumbing Forum frequently point out, “out of sight, out of mind” is a costly approach when it comes to water heaters.

According to the U.S. Department of Energy, sediment accumulation is the #1 cause of reduced efficiency and premature failure in tank-style water heaters. In hard water areas (which cover over 85% of U.S. homes, per the U.S. Geological Survey), minerals like calcium and magnesium settle at the tank’s bottom, forming a stubborn layer that insulates the burner from the water. This forces your heater to work harder, raising energy bills by up to 30% over time.

What Does the Terry Love Plumbing Forum Recommend?

The Terry Love Plumbing Forum—founded by veteran plumber Terry Love—is widely respected in the plumbing community for its no-nonsense, experience-based advice. Forum members, including licensed plumbers and DIY homeowners, consistently advocate annual flushing for most tank-type water heaters.

“If you don’t flush your heater, you’re basically paying to heat a rock,” says one long-time forum contributor with 22 years in residential plumbing.

The consensus: Yes, you should flush your water heater drain—unless you have a tankless (on-demand) system, which doesn’t store water and therefore doesn’t accumulate sediment the same way.

Tank vs. Tankless: Does Flushing Apply to Both?

While tankless units don’t require “draining” in the traditional sense, they do need periodic descaling with vinegar or a commercial descaler. Confusing the two is a common mistake—so always confirm your system type first.

For more on how water heaters work, see this overview on Wikipedia .

Step-by-Step: How to Safely Flush Your Water Heater

Flushing is straightforward but requires caution. Never skip the safety steps—hot water and pressure can cause serious injury.

Tools You’ll Need:

• Garden hose
• Bucket (optional)
• Adjustable wrench
• Towels
• Heat-resistant gloves

Instructions:

1. Turn off the power
   • Gas heaters: Turn the dial to “Pilot”
   • Electric heaters: Flip the breaker off at your electrical panel
2. Shut off the cold water supply
   Locate the valve on the cold water inlet pipe (usually marked “C” or blue) and turn it clockwise.
3. Let the tank cool
   Wait 2–3 hours until water drops below 120°F (49°C). Hot water under pressure is dangerous.
4. Attach a hose to the drain valve
   Route it to a floor drain, outside, or into a large bucket.
5. Open a hot water faucet
   (e.g., kitchen sink) to prevent vacuum lock and allow smooth drainage.
6. Open the drain valve
   Let water flow until it runs clear—this may take 5–15 minutes. If flow stops, sediment may be clogging the valve. Close it, briefly open the cold water supply to stir sediment, then drain again.
7. Close the drain valve, remove the hose, turn cold water back on, and let the tank refill (listen for gurgling to stop).
8. Restore power
   Turn the gas back to “On” or reset the electric breaker.

💡 Pro Tip: If your drain valve leaks after flushing, replace it with a ball valve (¼-turn type)—they’re more durable and less prone to clogging.

Pros and Cons: To Flush or Not to Flush?

✅ Advantages of Flushing

• Extends water heater life (from ~8 to 12+ years)
• Improves efficiency—saves $20–$60/year on energy bills
• Prevents rumbling or popping noises caused by trapped steam under sediment
• Reduces risk of tank corrosion and leaks

❌ Potential Drawbacks

• Time and effort (30–60 minutes)
• Risk of valve breakage if old/dry (common in units >10 years)
• Water waste (~20–50 gallons per flush)

However, forum veterans stress: “Replacing a $1,200 water heater costs far more than 30 minutes of your Saturday.”

Real-World Case: What Happens If You Don’t Flush?

A 2023 case shared on the Terry Love Plumbing Forum involved a homeowner in Phoenix (hard water city) who never flushed their 6-year-old heater. When it failed, the plumber found 3 inches of compacted sediment—equivalent to a brick—on the tank bottom. The unit was corroded beyond repair.

By contrast, another user in Seattle flushes annually and reports their 14-year-old heater still runs like new. “The $0 cost and 20 minutes saved me thousands,” they wrote.

FAQ Section

Q: How often should I flush my water heater?

A: Once a year is standard. If you live in a hard water area (check your water report), do it every 6 months.

Q: Can flushing damage my water heater?

A: Rarely—if done correctly. The main risk is breaking an old, corroded drain valve. If your unit is over 10 years old, consider hiring a plumber or replacing the valve beforehand.

Q: My water looks rusty after flushing—is that normal?

A: Slight discoloration is common the first time you flush an older unit. If it persists after 2–3 flushes, you may have internal corrosion—consult a professional.

Q: Do electric and gas water heaters need the same flushing process?

A: Yes, the flushing steps are nearly identical. The only difference is how you shut off the power (gas control knob vs. circuit breaker).

Q: Can I flush my water heater myself, or should I call a plumber?

A: Most DIYers can handle it. But if you’re unsure, uncomfortable with hot water systems, or have an older unit, a plumber ($100–$150) can do it safely and inspect for other issues.

Q: What if my drain valve won’t open or is clogged?

A: Try gently tapping it with a wrench or using pliers (carefully). If it’s stuck, don’t force it—you could cause a leak. Replace it with a new brass ball valve during your next maintenance window.

Conclusion

So, should you flush your water heater drain or not? Based on years of collective wisdom from the Terry Love Plumbing Forum, real-world data, and energy experts—the answer is a clear yes for tank-style units. It’s one of the simplest, lowest-cost maintenance tasks that delivers outsized benefits: lower bills, quieter operation, and a longer-lasting system.

Don’t wait for a rumble, a leak, or a cold shower to act. Set a calendar reminder, grab a hose, and give your water heater the care it deserves.

👉 Found this guide helpful? Share it with a friend or on social media! A quick share could save someone from a flooded basement or an unexpected $1,500 replacement bill.

Your water heater works hard for you—return the favor with 20 minutes a year.