11
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Noritz · Tankless Water Heaters
Ignition failure: unit could not light burner.
Quick Answer
Error code 11 on your Noritz Tankless Water Heaters means: Ignition failure: unit could not light burner.. This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
How to Fix It
1
Check gas supply is available and valves are open.
2
Inspect vent path for blockages.
3
Restart unit once after checks.
4
Have licensed contractor test ignition and gas pressure.
5
Clean/replace ignition components as needed.
Pro Tip
This issue typically requires professional diagnosis. Attempting this fix without proper training could cause further problems.
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