Generac Service Dealer Installed and Serviced Generator for Sale. Used Generac / Guardian 16,000 watt home standby generator with 100 amp ATS (RTS-N-100) 240V, 1PH. 2007 model 5283. This generator unit was professionally installed by us and was serviced regularly under service contract. We just tested this generator and removed from service after VERY light use. Delivery and installation services available in the Tampa Bay area. $2000 plus shipping.