Came out today for a Weil McLain boiler model #cg-6-spdn, cp #3107747. Upon arrival the homeowner stated that the system would come on but not heat the home. I removed the access panel and noticed that the system has a standing pilot and it was not lit. I tried to light the pilot but had no success. I removed the pilot assembly and noticed that the thermocouple was severely charged. I recommend replacing the thermocouple to start and the homeowner agreed. I replaced the thermocouple and lit the pilot. Once I powered the system back up the system ignited. The systems burners and burner box are covered in dust . I highly recommended performing preventative maintenance for the boiler. The homeowner stated that he would schedule another time for maintenance. The system is operating at this time.