Safety first: Turn off power before opening the cabinet. Use caution on ladders or roofs when inspecting vent terminations.

Step 1 – Inspect intake and exhaust: Check both terminations for obstructions and clearances. Remove any debris and ensure screens are not clogged.
Step 2 – Verify vent configuration: Compare installed vent lengths, diameters, and number of elbows to Navien specifications. Excessive length or elbows can cause E010. Correct any non‑compliant venting.
Step 3 – Check condensate drainage: Ensure the condensate trap is not overfilled and the drain line is not blocked. Standing condensate in the vent can alter air pressure.
Step 4 – Inspect blower and pressure tubing: With power off, check the blower wheel for debris and ensure it spins freely. Inspect the tubing to the air pressure sensor for cracks or blockages.
Step 5 – Professional testing: A technician can measure actual air pressure and blower speed, and replace the blower or pressure sensor if out of spec.

Do not operate the boiler with known venting issues; improper venting can lead to carbon monoxide hazards.

Boiler displays E010 and shuts down, often during or after a heating cycle

Possible Causes