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E005

Navien Boiler Error Code E005 – Flame Loss During Operation

Understanding Navien E005 error code, why flames are lost during operation, and when to call for professional boiler repair in Greater Vancouver.

What This Boiler Error Code Means

Error code E005 on your Navien boiler indicates flame loss during operation. This means the boiler successfully ignited and was running normally, but the flame was unexpectedly lost while the unit was calling for heat.

This is different from E003 (ignition failure) because the boiler did light initially. The flame sensing rod detected loss of flame and shut down the boiler as a safety precaution.

Is It Safe to Run the Boiler?

NO - Do not continue operating

Flame loss during operation indicates an unsafe condition. While one occurrence might be a temporary issue, repeated flame loss can indicate serious problems with gas supply, venting, or internal components.

Common Causes

Dirty or Failing Flame Rod
Carbon buildup or deterioration on the flame sensing rod preventing proper flame detection even when flame is present.
Intermittent Gas Supply
Fluctuating gas pressure, partially blocked gas line, or gas valve malfunction causing inconsistent fuel delivery.
Venting or Combustion Air Issues
Blocked exhaust vent, restricted air intake, wind-induced backdraft, or venting system problems disrupting combustion.
Condensate Drain Blockage
Clogged condensate trap or drain causing pressure issues that can extinguish the flame.
Heat Exchanger or Burner Problems
Dirty burner assembly, heat exchanger blockage, or combustion chamber issues affecting flame stability.

What You Can Check (Safe Steps Only)

Check exterior vent terminations

Inspect for ice buildup, snow blockage, bird nests, or other obstructions. Clear visible external blockages only.

Verify consistent gas supply

Ensure other gas appliances in your home are working normally without interruption.

Note weather conditions

High winds can sometimes cause flame loss. If error occurs only during extreme weather, this may be a clue for the technician.

Attempt one reset

If error persists or returns within 24 hours, professional service is required.

When to Stop and Call a Boiler Technician

E005 error occurs more than once

Boiler cycles on and off repeatedly (short cycling)

You notice unusual smells or sounds from the boiler

Error happens at a specific point in the heating cycle

Your home is without reliable heat

Important: Flame loss can indicate dangerous conditions including incomplete combustion, carbon monoxide risk, or mechanical failure. Professional diagnosis is essential.

Same-Day & Emergency Boiler Repair – Greater Vancouver

ROMA Heating & Cooling - Navien Boiler Specialists

Our licensed technicians are experts in diagnosing and repairing Navien E005 flame loss errors. We carry specialized combustion analysis equipment and genuine Navien parts for same-day repairs across Greater Vancouver.

Call 778-909-5731 for Immediate Service

Serving Vancouver, Burnaby, Richmond, Surrey, Coquitlam, North Vancouver, and all of Greater Vancouver with emergency boiler repair since 1999.

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