Pride Plumbing was called out for a Rinnai natural gas tankless water heater not working - it was showing error code 55 which meant it was time for it to be serviced. We knew that the unit was installed just 6-months ago and it wasn't time yet for a descale service. So, we went into the Rinnai setup app and found that the unit was set for 6-month service intervals. We disabled that setting and set it so that it could be serviced at will. After adjusting the settings in the app, we set the unit's temperature to 125 degrees and tested it for proper operation.