

Navien Tankless Water Heater Not Producing Hot Water
Nothing is more frustrating than turning on the faucet and discovering your Navien tankless water heater is not producing hot water.
Whether the problem is a gas supply issue, ignition failure, water flow restriction, error code, scale buildup, or component failure, Hot Water Pros can diagnose the problem and restore reliable hot water service throughout Indianapolis and surrounding communities.
QUICK ANSWER
Why Your Navien Isn't Making Hot Water
Usually the unit has locked out on an error code, lost its gas or power supply, or isn't sensing water flow because of a clogged inlet filter or scale.
Top 3 causes
An error code lockout, often ignition (003), flame loss (012) or venting (109 or 110)
Gas or electrical supply problems
A dirty inlet filter or scale buildup from skipped maintenance
When to call a pro
If basic checks don't bring the hot water back, or the same code returns after a reset, schedule Navien tankless water heater repair. Older unit with repeat problems? Compare the repair with a new tankless water heater.
BEFORE YOU CALL
Safe Things To Check First
Error code: If the display shows a code, open its guide: 003, 012, 109, 110, 351 or 515.
Power: Check the heater's breaker, and the GFCI outlet if the unit plugs in.
Gas and water: Make sure the valves to the heater are open and your other gas appliances work. If a gas valve is off and you don't know why, call us first.
One reset: Reset the unit once. If there's still no hot water, call.
Leave it to a pro: gas lines, burner and ignition parts, wiring and anything inside the cover. Our Carefree tankless plan includes annual service.
Still no hot water? Call 317-922-9043 or book online.
Why Is My Navien Not Producing Hot Water?
Several issues can prevent a Navien tankless water heater from heating water properly.
Some problems are simple, while others require professional diagnosis.
Common causes include:
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Error codes
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Gas supply problems
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Ignition failures
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Dirty inlet filters
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Scale buildup
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Flow sensor problems
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Venting restrictions
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Electrical issues
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Control board faults
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Maintenance neglect
Common Navien Error Codes Associated With No Hot Water
Many homeowners experience no hot water when one of the following codes appears:
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Error 003
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Error 012
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Error 109
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Error 110
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Error 351
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Error 515
If your Navien is displaying an error code, diagnosing the underlying issue is often the fastest path to restoring hot water.
Can I Fix My Navien Myself?
Homeowners can safely check:
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Circuit breaker position
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Gas shutoff valve
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Water supply valves
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Air intake and exhaust vents
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Error code display
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Visible leaks
If the issue persists after basic checks, professional diagnosis is usually recommended.
Signs Your Navien Needs Professional Repair
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No hot water
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Unit repeatedly shuts down
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Frequent error codes
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Inconsistent temperatures
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Unusual noises
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Ignition failures
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Water leaks
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Reduced water flow
No Hot Water From Your Navien? Don't Ignore The Warning Signs
Many no-hot-water complaints begin with minor issues such as dirty filters, vent restrictions, scale buildup, or ignition problems. Left untreated, these issues can lead to larger repairs and repeated shutdowns.
Hot Water Pros can quickly diagnose the problem and restore reliable hot water to your home.
Call Today: 317-922-9043
Why Indianapolis Homeowners Choose Hot Water Pros
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Licensed Indiana plumbing contractor
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Experienced with Navien tankless systems
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Same-day service available
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Water pressure diagnostics
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Tankless flushing and maintenance
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Upfront pricing
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Serving Indianapolis, Carmel, Fishers, Westfield, Noblesville, Greenwood, Brownsburg, Whitestown, and Zionsville
We Repair All Major Navien Models
Our technicians service all major Navien tankless water heater models including:
• Navien NPE-240A2
• Navien NPE-210A2
• Navien NPE-180A2
• Navien NPE-S2 Series
• Navien NCB Series
• Navien NHB Series

Navien NPE-240A2
199,000 BTU

Navien NPE-210S2
180,000 BTU

Navien NPE-240S2
199,000 BTU

Navien NPE-180A2
150,000 BTU
Navien Not Producing Hot Water FAQs
Why is my Navien running but not producing hot water?
Common causes include ignition failures, gas supply problems, scale buildup, flow restrictions, and component failures.
Can low water pressure cause a Navien to stop producing hot water?
Yes. Low flow conditions can prevent proper operation.
Can a dirty filter cause no hot water?
Yes. A clogged inlet filter can restrict water flow and affect performance.
Why does my Navien have power but no hot water?
The issue may involve gas supply, ignition, sensors, venting, or internal components.
How much does it cost to fix a Navien with no hot water?
Repair costs depend on the cause. We provide upfront pricing before any work begins, and warranty coverage is available on qualifying repairs.
Do you repair Navien water heaters with no hot water in Indianapolis?
Yes. Hot Water Pros provides diagnosis and repair for Navien tankless water heaters that are not producing hot water throughout Indianapolis and surrounding communities, with same-day service available. Call or text 317-922-9043 to schedule.
Locally Owned & Operated
Hot Water Pros proudly provides Navien repair throughout Indianapolis, Carmel, Fishers, Westfield, Noblesville, Greenwood, Brownsburg, Whitestown, Cicero, and Zionsville. Our Navien trained technicians can quickly diagnose tankless water heaters and restore reliable hot water to your home.

TANKLESS WATER HEATER SERVICES
WE INSTALL. WE SERVICE. WE GUARANTEE.
From installation to maintenance and repairs, we handle all your tankless water heater needs with honest pricing, expert workmanship, and the best brands in the industry.
Professional installation of tankless water heaters for maximum performance and efficiency.
Professional replacement of tankless water heaters for maximum performance and efficiency.
Fast diagnostics and expert repairs to keep your tankless water heater running like new.
Extend the life of your unit and maintain peak performance with professional tankless flushing and cleaning.
CUSTOMER REVIEWS
What Our Customers Say
“They are extremely professional experts who show up same / next day and provide top quality services.”
Jen W.
“Hot Water Pros did exceptional work for me; they will be my go-to for all future plumbing needs.”
Andrew S.
“They came out and replaced my hot water heater today, the same day that I called them to see if they could help me!”
Laura B.

