The flame pattern of the burner in my Alde boiler is very uneven and yellow and the boiler sometimes goes out for no apparent reason. What is the reason for this?

This is usually due to one of two causes, principally that the boiler is in need of a service which could be affecting the performance of the burner and the pilot flame, or secondly if the yellow flame is accompanied by a ‘droning’ noise, then it is usually caused by low gas pressure. In this case, it is recommended that the installation is inspected by an experienced Engineer. There are other causes, but these are the two most frequently experienced.

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