BoilerFaultCodesWhat the manual says
Manufacturer manualHot water operation burner is on
From this model's manual
Verified against the Vaillant Ecotec 65kw installation & service manual, page 35.
What causes this fault?
This status occurs when the boiler detects a demand for hot water and successfully ignites the burner to meet that need. It is not a malfunction, but rather a confirmation that the internal components are operating correctly to transfer heat to your water supply. As long as you have hot water at your taps, the boiler is performing its job exactly as intended.
DIY fix possible
No action is required as this is a status code, not a fault.Check your taps or cylinder to ensure hot water is being delivered as expected.The code will disappear once the hot water demand is met.
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