Diagnose Your
Water Heater
in Minutes
Search error codes, fix no hot water problems, or scan your unit — and follow step-by-step HVAC troubleshooting built for your exact model.
Supported brands & systems
Rheem
Tankless & Tank
A.O. Smith
Tank & Hybrid
Navien
Gas Tankless
Rinnai
Gas Tankless
Bradford White
Tank Gas
Bosch
Electric
Noritz
Gas Tankless
Takagi
Gas Tankless
Rheem
Tankless & Tank
A.O. Smith
Tank & Hybrid
Navien
Gas Tankless
Rinnai
Gas Tankless
Bradford White
Tank Gas
Bosch
Electric
Noritz
Gas Tankless
Takagi
Gas Tankless
How it works
Three steps from problem to fix
Whether you're tackling tankless water heater troubleshooting or a no hot water complaint — this is the fastest path to a fix.
Identify your unit
Scan the rating plate or pick your brand and model. Works for all major tankless and tank systems.
Search the issue
Enter the error code or describe the symptom — E1, E11, no hot water, ignition failure.
Follow guided steps
Get a step-by-step water heater repair checklist built for your exact unit. No manual needed.
Why HeatSync
Built for the field
Everything a technician needs to diagnose water heater problems and HVAC issues fast — on site, without manuals.
2-minute diagnosis
From error code to root cause faster than finding the manual.
All major brands
Rheem, Navien, A.O. Smith, Rinnai, Bradford White — one tool.
No manuals needed
Structured flows built from OEM service procedures.
Works offline
No Wi-Fi required. Diagnose on any job site anywhere.
Coverage
Supported systems
From tankless water heater troubleshooting to gas and electric tank diagnostics — one tool, all systems.
Navien, Rinnai, Rheem RTGH
Rheem RETEX, Bosch Tronic
A.O. Smith, Bradford White
Rheem ProTerra, A.O. Smith Voltex
FAQ
Common questions
Answers to the most frequent water heater repair and HVAC troubleshooting questions.
- Why is my water heater not producing hot water? expand_more
- Common causes include a tripped circuit breaker, faulty heating element, failed thermostat, or a gas supply issue. Use HeatSync to search your error code or describe the symptom for a step-by-step diagnosis.
- What does the E1 error code mean on a water heater? expand_more
- E1 typically indicates an ignition failure on tankless water heaters such as Navien, Rinnai, and Noritz. It means the burner failed to light. HeatSync walks you through the exact checks for your specific model.
- How do I reset a tankless water heater? expand_more
- Most tankless units have a reset button on the front panel. Power cycle the unit, wait 30 seconds, then restart. If the error code returns, use HeatSync to diagnose the underlying cause.
- What brands does HeatSync support? expand_more
- HeatSync supports Rheem, A.O. Smith, Rinnai, Navien, and Bradford White — covering tankless (gas and electric) and heat-pump hybrid units.
- What is the ignition failure error on a water heater? expand_more
- Ignition failure means the burner failed to light within the allowed time. Causes include low gas pressure, a blocked flue, dirty flame sensor, or a faulty igniter. HeatSync provides guided HVAC troubleshooting steps specific to your unit.
Start Diagnosing Now
Search any water heater error code or describe your symptom. Get step-by-step guidance in seconds.
Works on any device · No app install · Covers Rheem, Navien, A.O. Smith, Rinnai, Bradford White