The most useful form of the Hottel-Whiller-Bliss generalized performance equations for flat plate collector utilizing heat removal factor and loss coefficients is used to model a solar oven- water heating system for low thermal process application. The water heating system was designed, tested and evaluated with a daily collector efficiency of 51.82%, an average daily solar radiation of 689.23 (w/ºc) per day and a useful gain by collector of 563.85 (w/ºc). Loss in collector is 116.39 (w/ºc) and total average daily heat gain by water in collector is 292.26 (w/ºc). Average Daily storage heat capacity of 582.83 (KJ) and the daily convected heat delivered to test chamber is 147.07 (KJ). The overall System efficiency of 25.24% was obtained.