noise from ultracom 24 hxi boiler

[Popeye7564]

I have an ultracom 24 hxi boiler which has been making a very loud groaning noise and heavy vibration intermittently on start up. The noise can last for up to 4 minutes. The flame in the furnace is orange during the noisy period, suggesting the gas/air mix is wrong. The noise and vibration stops when the flame turns blue, the fan is quiet and runs no problem, so that is not the problem. Gas pressure is about 20mb. When the boiler is running, the ch and hotwater heats up quickly. The boiler is about 5 years old and has been no problem prior to this fault. There has been multiple visits by the service engineer and various checks and adjustments, but all to no avail. I believe the gas modulating was turned down at the last visit, but no improvement. The furnace hss been inspected and cleaned and new gsskets fitted.

Now grasping at straws.... any suggestions out there?

 

[gaspro1981]

Yh employ someone who knows what they are doing

 

[Agile]

Get a better service engineerf?

 

[Popeye7564]

The service engineer hss actually been very good and has spoken to the manufacturer twice already. They have made suggestions for adjustments, none of which have worked, so I am happy that he is doing his best, but it is very tricky one as it is intermitent. He has only been able to witness the fault once, mostly he just watches the video clips I take of the noise and furnace panting. Its quite refreshing that he is not the usual type that comes in and just keep on changing parts until they eventually find the fault!

Any useful checks/comments appreciated!

 

[bazdaman]

You have been given your answer previos, get a better engineer