Abstract: Disclosed is a boiler blockage detection system and method utilizing inputs from a pressure sensing elements. A logic circuit may determine a boiler firing rate based on an input signal from the combustion controller. An indication of the exhaust pressure level and an indication of the inlet pressure level are received. A pressure differential between the exhaust pressure level and the inlet pressure level is determined. Alternatively, a pressure differential transmitter may determine the pressure differential. The determined pressure differential is compared to a predetermined pressure level differential threshold. The predetermined pressure level differential threshold is dependent on the determined firing rate. Based on a result of the comparison of the determined pressure differential to the predetermined pressure level differential threshold, it may be determined that there is a blockage of an intake or an exhaust of the boiler. In response to the blockage determination, an interrupt signal is output.

Abstract: A system and method for electrically interconnecting a plurality of fuel cells to provide dense packing of the fuel cells. Each one of a plurality of fuel cells has a plurality of discrete electrical connection points along an outer surface. Electrical connections are made directly between the discrete electrical connection points of adjacent fuel cells so that the fuel cells can be packed more densely. Fuel cells have at least one outer electrode and at least one discrete interconnection to an inner electrode, wherein the outer electrode is one of a cathode and an anode and wherein the inner electrode is the other of the cathode and the anode. In tubular solid oxide fuel cells the discrete electrical connection points are spaced along the length of the fuel cell.