Tankless Water Heater Installation & Maintenance
Expert installation, flushing/descaling, and repair for Navien, Rinnai, and all major tankless brands.
Why Tankless Water Heaters?
Tankless (on-demand) water heaters have become increasingly popular in Southern California homes for good reason. Unlike traditional tank water heaters that continuously heat 40-50 gallons of water, tankless units heat water only when you need it—providing endless hot water while reducing energy costs by up to 30%.
However, tankless water heaters require specialized knowledge for proper installation and maintenance. Walnut's hard water is particularly challenging for tankless units, making regular flushing and descaling essential for optimal performance and longevity. We provide expert service for all major tankless water heater brands like Navien and Rinnai.
Flushing & Descaling Service
Essential maintenance for Walnut's hard water
Walnut, CA has notoriously hard water with high mineral content. Over time, calcium and lime deposits (scale) build up inside your tankless water heater's heat exchanger, reducing efficiency and eventually causing system failures. Annual flushing with a descaling solution removes this buildup and restores peak performance.
What Happens During a Flush?
- 1Isolate the unit from the water supply using service valves
- 2Connect a circulation pump with food-grade descaling solution
- 3Circulate the solution through the heat exchanger for 45-60 minutes
- 4Flush the system with clean water to remove loosened deposits
- 5Inspect and clean the inlet filter screen
- 6Check error code history and verify proper operation
When to Schedule Flushing
- Annually for most Walnut homes (hard water accelerates buildup)
- When you notice fluctuating water temperature
- If the unit displays scale-related error codes
- Before winter to ensure peak heating capacity
- If water flow seems reduced from previous performance
Error Code Diagnosis
Expert troubleshooting for Navien, Rinnai & more
Tankless water heaters display error codes when they encounter problems. While some codes indicate simple issues like a clogged filter, others signal more serious failures requiring professional repair. Our technicians are trained to diagnose and resolve error codes for all major brands.
Common Navien Error Codes
E003
Ignition failure—gas supply or igniter issue
E016
Overheating—scale buildup or flow restriction
E030
Exhaust temperature sensor failure
E110
Exhaust blockage—check venting
E302
Water leak detected inside unit
E407
Inlet thermistor malfunction
Common Rinnai Error Codes
Code 10
Air supply or exhaust blockage
Code 11
No ignition—gas valve or igniter
Code 12
Flame failure during operation
Code 14
Thermal fuse activated (overheating)
Code 16
Over temperature warning
Code 61
Combustion fan failure
Note: If your unit displays an error code, note the code before resetting the unit. This information helps our technicians diagnose the issue more efficiently.
New Installation
Upgrading from tank to tankless
Installing a tankless water heater involves more than swapping out your old tank. Proper sizing, gas line upgrades, venting modifications, and electrical connections all require careful planning and code-compliant installation. We handle every aspect of the conversion to ensure trouble-free operation.
Installation Considerations
Sizing
We calculate your home's hot water demand based on the number of fixtures and simultaneous use patterns to select the right capacity unit.
Gas Line Upgrades
Tankless units require larger gas supply lines than tank heaters. We assess your current gas line capacity and upgrade as needed.
Venting
Most tankless units require stainless steel Category III or PVC venting, different from traditional tank heater venting.
Condensate Drainage
High-efficiency condensing units produce acidic condensate that must be properly drained or neutralized.
Brands We Install
Navien
Rinnai
Noritz
Rheem
Takagi
Bosch
Tankless vs. Tank Water Heaters
Wondering if tankless is right for your home? Here's how they compare:
| Feature | Tankless | Tank |
|---|---|---|
| Hot Water Supply | Unlimited | Limited to tank size |
| Energy Efficiency | Up to 30% savings | Standby heat loss |
| Lifespan | 20+ years | 10-12 years |
| Upfront Cost | Higher | Lower |
| Maintenance | Annual flushing required | Annual drain recommended |
| Space Required | Wall-mounted, compact | Floor space required |
Why Choose Walnut Plumbing?
- Experienced in servicing all major tankless brands, including Navien, Rinnai, and Rheem.
- Licensed California Contractor #1005582
- 20+ years serving Walnut families since 2005
- Same-day service valves installation available
- We stock common replacement parts
- Transparent pricing with written estimates
Speak with an Expert
Due for a flush? Have an error code? Call now for fast, expert service.
Licensed & Insured
CSLB #1005582
California State Contractor License
Hard Water Alert
Walnut, CA
Our area's hard water means tankless units need annual flushing to prevent scale buildup and maintain efficiency.
Related Services
Speak with a Local Walnut Expert Today
Regular maintenance extends the life of your tankless water heater and ensures reliable hot water year-round.