Re: Bosch KDN30X00GB
Contact BSH on 0844 8928979 or for Ireland call 00 353 1450 2655.
You have a 2 year guarantee on that appliance 😀
Before calling them out though, you might want to consider giving the appliance a 48 hour power down to fully defrost it and see if the noise returns. If it does then you have a genuine problem, if not it maybe that for some reson the defrost has not been effective ie – door left ajar allowing more than usual ice build up in and around the frost free fan.
HTH
Greg