What is an authorised service centre?
An authorised service centre is the manufacturer or a company that they have trained and deem as responsible to service and maintain their products so they will operate as intended.
EN365: 2004 is the Standard that is applied to this and checks will also satisfy LOLER or PUWER or both depending on the product. Under EN365: 2004 the training is specific to certain products and each manufacturer will be able to provide you with a list of their authorised service centres.
Do not be surprised if some manufacturers only deem themselves competent to do this, this is more common than you may think.
If your unit has not been serviced by an authorised service centre it may well not work correctly and you would be in breach of the PPE regulations.