I have recently purchased a used Ecoteck (Ravelli) Monica Plus. I noted that the flue was fairly dirty and that the flame appears quite lazy with yellow tips. Im planning to give it all a throrough clean prior to installation but Im looking for a service or technicians manual that covers the finer adjustments. This model is prior to the RDS version. Can anyone be of assistance please, the information contained in easily obtainable “owners & installation manual” is very limited at best. Appreciate any help. Thanks.