How to Flush a Water Heater Tank — West Des Moines, Iowa
Complete checklist with climate-adjusted recommendations for West Des Moines, Iowa
Overview
Attach a hose to the drain valve and flush until water runs clear. Removes sediment that reduces efficiency and shortens tank life.
Step-by-Step Guide
Turn off the heat source
For a gas water heater, turn the gas valve to the 'pilot' or 'off' position. For an electric water heater, switch off the dedicated breaker at the electrical panel. Never drain a tank with the heating element active — it will burn out if exposed to air.
Turn off the cold water supply
Locate the cold water inlet valve on top of the heater and close it by turning it clockwise. This prevents new water from entering while you drain.
Let the water cool
Wait at least 30 minutes (ideally 1-2 hours) for the water inside to cool to a safe temperature. Alternatively, run hot water at a nearby faucet for several minutes to speed cooling, but be cautious — the water will be scalding at first.
Connect a garden hose to the drain valve
Locate the drain valve near the bottom of the tank. Attach a standard garden hose and run the other end to a floor drain, driveway, or bucket outside. Make sure the hose runs downhill from the valve — the drain relies on gravity.
Open the pressure relief valve
Lift the lever on the temperature and pressure (T&P) relief valve on the side or top of the tank. This breaks the vacuum and allows the tank to drain freely. Place a bucket underneath in case water drips from the overflow pipe.
Open the drain valve and flush
Open the drain valve slowly with a flathead screwdriver or by hand. Let water flow until it runs clear. If sediment clogs the valve, briefly open and close the cold water supply in short bursts to stir it up. Expect rusty or sandy water initially — this is the sediment you are removing.
Close everything and refill the tank
Close the drain valve, remove the hose, and close the T&P relief valve. Open the cold water supply valve fully. Open a hot water faucet upstairs to let air escape as the tank refills. When a steady stream flows from that faucet (no sputtering), the tank is full.
Restore the heat source
For gas, turn the gas valve back to 'on' and relight the pilot if needed. For electric, switch the breaker back on. Wait 30-60 minutes for the water to heat up before using hot water. Check the drain valve for drips and tighten if necessary.
What You'll Need
Tools
- - Garden hose
- - Flathead screwdriver
- - Adjustable wrench
- - Bucket
Materials
- - Teflon tape (if drain valve drips after closing)
Cost Estimates
DIY Cost
$0 - $10
Professional Cost
$80 - $200
Safety Tips
- Water inside the tank can exceed 140°F — let it cool before draining or wear heat-resistant gloves.
- Never turn on the heating element or gas burner while the tank is empty or partially full.
- If the T&P valve is stuck or leaks continuously after you close it, replace it before using the heater.
- Route the hose away from landscaping — hot, sediment-filled water can damage plants.
When to Call a Professional
Call a plumber if the drain valve is corroded shut, the T&P valve won't reseat, you notice the tank leaking from the bottom (indicating internal corrosion), or the water heater is more than 10 years old and has never been flushed.
Pro Tip
Flush your water heater once a year — twice a year if you have hard water. Regular flushing can extend tank life by 3-5 years and improve heating efficiency by up to 20%.
Common Mistakes to Avoid
- Forgetting to turn off the heating element before draining, which burns out electric elements.
- Not opening the T&P valve, causing a vacuum that prevents the tank from draining.
- Running the hose uphill so water backs up instead of flowing out.
- Skipping the cooldown period and getting burned by scalding water.
- Not fully refilling the tank before turning the heat source back on.
Local Plumbers in West Des Moines
Bill Rhiners Plumbing Heating & Cooling
West Des Moines, IA
(515) 987-1800Home Run Plumbing
West Des Moines, IA
(515) 654-3339Cook Plumbing Corporation
Des Moines, IA
(515) 225-9532
Complete Plumbing Services LLC
West Des Moines, IA
(515) 490-1882Founding Member
Premium spot in West Des Moines
Ambassador
Lead the West Des Moines community
Founding Member
Premium spot in West Des Moines
West Des Moines Housing Market
Median Household Income
$84,925
Median Home Value
$286,300
Median Rent
$1,194/mo
Homeownership Rate
57.4%
Population
69,893
Median Year Built
1993
Source: U.S. Census Bureau, ACS 2023 5-Year Estimates
Fair Market Rents — West Des Moines
Studio
$1,063/mo
1 Bedroom
$1,109/mo
2 Bedroom
$1,318/mo
3 Bedroom
$1,794/mo
4 Bedroom
$1,841/mo
Source: HUD FY2026 Fair Market Rents — Des Moines-West Des Moines, IA HUD Metro FMR Area
This Task Appears On
Related How-To Guides
How to Check Washing Machine Hoses
Inspect for bulges, cracks, or leaks. Replace rubber hoses with braided stainless steel every 5 years. Burst washing machine hoses are one of the top causes of residential water damage.
How to Locate and Test Your Main Water Shut-Off Valve
Know where your main shut-off valve is and test that it turns. A stuck valve during an emergency means a flooded house and thousands in damage.
How to Inspect Pipes for Corrosion
Check for green or white deposits on copper pipes and rust on galvanized pipes. Catching corrosion early prevents leaks, low water pressure, and costly emergency repairs.