Tankless Water Heater Maintenance: Keep Your System Running Like New
- Kirill Anikin
- Feb 25
- 5 min read
Updated: Feb 25
"An ounce of prevention is worth a pound of cure." – Benjamin Franklin
Tankless water heaters are a game-changer for homeowners and businesses alike. They provide endless hot water on demand, improve energy efficiency, and take up less space than traditional tank models. But just like any high-performance system, they require regular maintenance to function at their best! Neglecting routine upkeep can lead to inconsistent hot water, mineral buildup, and costly repairs. Let’s dive into the specifics of tankless water heater maintenance to ensure your unit stays in top shape for years to come.
Why Regular Tankless Water Heater Maintenance Matters
Unlike traditional water heaters with storage tanks, a tankless water heater heats water only when needed. This means it's constantly exposed to mineral deposits, high temperatures, and potential wear and tear. Proper maintenance:
Prevents scale buildup that can restrict water flow and reduce efficiency.
Ensures consistent water temperature and optimal performance.
Extends the lifespan of your unit, saving you from premature replacements.
Reduces the risk of costly repairs by catching small issues early.
Step-by-Step Guide to Tankless Water Heater Maintenance
1. Flush the System to Remove Scale and Sediment
Over time, hard water minerals like calcium and magnesium can build up inside your tankless water heater, leading to clogs and inefficiency. Flushing the system once a year is essential, especially if you have hard water.
How to Flush a Tankless Water Heater
Turn off the power (gas or electric) to the unit.
Close the water supply valves to prevent new water from entering.
Attach a submersible pump and two hoses to the service ports—one for incoming vinegar solution and one for outgoing wastewater.
Run white vinegar through the system for at least 45 minutes to dissolve scale deposits.
Flush with clean water to remove any remaining vinegar.
Reconnect everything and turn the power back on.
💡 Pro Tip: If you live in an area with extremely hard water, consider installing a water softener to reduce mineral buildup.
2. Clean or Replace the Inlet Filter
Your tankless water heater has a small filter that prevents debris from entering the unit. If it gets clogged, it can reduce water pressure and affect performance.
How to Clean the Inlet Filter
Locate the filter near the cold water inlet.
Remove it carefully and rinse it under warm running water.
Use a soft brush to remove any stubborn debris.
Reinstall the filter and ensure it’s secure.
Checking this filter every few months can prevent unexpected pressure drops and flow issues.
3. Inspect the Venting System
A proper venting system ensures safe operation and prevents harmful gases like carbon monoxide from accumulating inside your home.
What to Check:
Look for blockages like dust, debris, or even birds’ nests in outdoor vents.
Ensure all vent pipes are securely connected and have no leaks.
If your unit is gas-powered, test for gas leaks using a soapy water solution.
If you notice any leaks or improper venting, contact a professional immediately.
4. Test the Temperature and Pressure Relief Valve
This safety feature prevents excessive pressure buildup inside the heater. A faulty valve can lead to dangerous pressure spikes or leaks.
How to Test It:
Place a bucket under the valve to catch water.
Lift the valve’s handle slightly—water should discharge briefly before stopping.
If no water comes out or it continues to leak, replace the valve.
5. Check for Error Codes and Unusual Noises
Many modern tankless water heaters display error codes when something is wrong. Keep an eye on the display panel and consult the manufacturer’s manual if a code appears.
E012 (Loss of Flame): Could indicate a gas supply issue or faulty ignition.
E029 (Scale Buildup): Time for a deep cleaning and flush!
Strange knocking sounds: Could be caused by trapped air, loose fittings, or sediment buildup.
If you experience inconsistent hot water or persistent error codes, consider calling a professional for further diagnosis.
When to Call a Professional
Symptoms That Indicate You Need Maintenance
Even with regular use, a tankless water heater will show signs when it needs maintenance. Here are some common indicators:
Inconsistent water temperature – If your hot water fluctuates or turns cold unexpectedly, mineral buildup may be restricting flow.
Reduced water pressure – A clogged inlet filter or scale accumulation can lower the pressure coming from your faucets.
Strange noises – Knocking or rumbling sounds often signal trapped air, scale buildup, or loose components.
Error codes on the display – Many units display warning codes for ignition failures, scale buildup, or venting issues.
Visible leaks or drips – Any moisture around the unit or pipes should be inspected immediately.
Increased energy bills – If your unit is working harder to heat water, efficiency has likely decreased due to mineral buildup.
If you notice any of these symptoms, it’s time to perform maintenance or call a professional to prevent further damage.
Step-by-Step Guide to Tankless Water Heater Maintenance
1. Flush the System to Remove Scale and Sediment
Over time, hard water minerals like calcium and magnesium can build up inside your tankless water heater, leading to clogs and inefficiency. Flushing the system once a year is essential, especially if you have hard water.
How to Flush a Tankless Water Heater
Turn off the power (gas or electric) to the unit.
Close the water supply valves to prevent new water from entering.
Attach a submersible pump and two hoses to the service ports—one for incoming vinegar solution and one for outgoing wastewater.
Run white vinegar through the system for at least 45 minutes to dissolve scale deposits.
Flush with clean water to remove any remaining vinegar.
Reconnect everything and turn the power back on.
💡 Pro Tip: If you live in an area with extremely hard water, consider installing a water softener to reduce mineral buildup.
While DIY maintenance can go a long way, some issues require expert attention. Call a licensed plumber if you notice:
A persistent drop in water temperature despite cleaning and flushing.
Visible leaks around the unit.
Frequent ignition failures or complete loss of hot water.
A hissing sound inside the heater, which could indicate internal pressure issues.
Final Thoughts
Regular tankless water heater maintenance ensures you get the best performance, energy savings, and longevity from your system. Flushing the unit, cleaning filters, inspecting venting, and testing safety valves are simple steps that can prevent expensive repairs down the road. Whether you tackle maintenance yourself or schedule an annual service with a professional, keeping your tankless water heater in peak condition is well worth the effort!
By staying proactive, you’ll enjoy endless hot water, lower energy bills, and peace of mind—because when it comes to home comfort, reliability is key! 🔥🚿
Ingenium Intuito Group specializes in expert heating, cooling, and gas solutions for residential and commercial properties. Contact us today for professional tankless water heater services!
Comentários