The MAST Upgrade tokamak has a suite of foil bolometers to measure the total radiated power from the plasma. Arrays of bolometers provide coverage of the main chamber and lower divertor radiation. Data is digitised and processed using novel FPGA-based electronics, offering improved compactness and new capabilities. A synthetic diagnostic has been developed to explore the quality of 2D reconstructions available from the system and to quantity the uncertainty on quantities such as the total radiated power. Measurements in the first campaign have demonstrated correct functioning of the diagnostic while also highlighting issues with electrical noise and some failure mechanisms of the detectors, as well as a significant neutral beam fast- particle loss mechanism.