The system just needs a service. With it being wireless I would change all batteries in the detectors once a year. You can get a new panel battery from your local city electrical or Screwfix etc.
Depending on how the panel is programmed the wireless low battery is set to notify you every 12 hours as standard.
Remember when you have changed the detectors batteries you have to wait 2 minutes then walk in front of them to send the tamper restore back to the panel. With the door contacts change the battery and open/close the door to send back the tamper restore to the panel.
With the bell take the bell hold off wire out from the panel, if the bell rings like normal then that is ok.
I also have been fitting Risco wireless for 15 years and if programmed/maintained properly then you will get no problems.