If you have a tankless water heater in your Mount Pleasant or Charleston home, you've made a smart choice for endless hot water and energy efficiency. But like all appliances, tankless water heaters need regular maintenance to keep performing at their best. One of the most important maintenance tasks is annual flushing, also called descaling.
What is Tankless Water Heater Flushing?
Flushing your tankless water heater involves circulating a descaling solution through the system to remove mineral buildup, particularly calcium and lime deposits. Here in the Lowcountry, our water contains minerals that can accumulate inside your tankless unit's heat exchanger over time.
Why Flushing is Critical in Charleston
Charleston area water tends to be harder than in many other regions, meaning it contains more dissolved minerals. These minerals can build up inside your tankless water heater's heat exchanger, causing:
- Reduced efficiency - Mineral buildup acts like insulation, making your unit work harder
- Higher energy bills - An inefficient unit uses more gas or electricity
- Shorter lifespan - Excessive buildup can damage internal components
- Inconsistent hot water - Mineral deposits can affect water flow and temperature
- Warranty violations - Most manufacturers require annual maintenance to keep warranties valid
Signs Your Tankless Water Heater Needs Flushing
Watch for these warning signs that indicate your unit needs professional descaling:
- Inconsistent water temperature during showers
- Longer wait times for hot water to reach faucets
- Unusual noises coming from the unit
- Error codes appearing on the display
- Reduced hot water flow rate
- Higher than normal utility bills
The Professional Flushing Process
While some homeowners attempt DIY flushing, professional service ensures the job is done safely and completely. Here's what Holy City Plumbing's technicians do during a tankless water heater flush:
- System shutdown and isolation - Safely disconnect power and water supplies
- Service valve connection - Connect pumps and hoses to circulate descaling solution
- Descaling solution circulation - Run specialized solution through the heat exchanger for 45-60 minutes
- Fresh water flush - Thoroughly rinse all descaling solution from the system
- Filter cleaning or replacement - Clean or replace inlet water filter
- System testing - Verify proper operation and temperature control
- Documentation - Provide maintenance records for warranty compliance
How Often Should You Flush Your Tankless Water Heater?
Most manufacturers recommend annual flushing, but Charleston's mineral-rich water may require more frequent service:
- Annual flushing - Minimum requirement for most homes
- Every 6-8 months - Homes with very hard water
- Quarterly - Commercial applications or high-usage homes
- As needed - Based on performance issues or error codes
DIY vs Professional Service
While descaling kits are available for homeowners, professional service offers several advantages:
Professional Benefits:
- Proper equipment and commercial-grade descaling solutions
- Experience identifying potential problems during service
- Warranty compliance documentation
- Safety - no risk of improper chemical handling
- Complete system inspection during service
DIY Risks:
- Improper chemical mixing can damage the unit
- Inadequate flushing may leave residue
- Safety concerns with gas connections and electrical components
- Potential warranty violations if not done correctly
Preventing Mineral Buildup
Between professional flushings, you can help prevent excessive mineral buildup:
- Install a water softener - Reduces minerals entering your tankless unit
- Replace inlet filters regularly - Clean or replace every 3-6 months
- Monitor water quality - Test hardness levels annually
- Schedule preventive maintenance - Don't wait for problems to develop
Cost of Professional Tankless Flushing
Professional tankless water heater flushing typically costs much less than major repairs or premature replacement. Consider the investment in annual maintenance against:
- Replacement costs ($2,000-$4,000+ for new tankless units)
- Higher energy bills from inefficient operation
- Potential water damage from system failures
- Lost warranty coverage from inadequate maintenance
Trust Holy City Plumbing for Tankless Maintenance
As your local Lowcountry plumbers since 2012, David and Kerry Greer understand the unique challenges of Charleston area water quality. We provide comprehensive tankless water heater maintenance including:
- Annual descaling and flushing service
- Filter replacement and cleaning
- Complete system inspection and testing
- Warranty compliance documentation
- Emergency repair service when needed
