A fuel-fired water heater having a top water outlet includes a water tank and a top cover assembly having the top water outlet to output water from the water tank. The water heater further includes a multi-pass heat exchanger that includes flue tubes positioned in the water tank. The water heater also includes a first plenum and a second plenum at a top end portion of the water heater. The first plenum provides a first hot gas flow path from a first set of the flue tubes to a second set of the flue tubes, and the second plenum provides a second hot gas flow path from a third set of the flue tubes to a fourth set of the flue tubes.