Machine head assembly and heat pump water heater

The utility model discloses a machine head assembly and a heat pump water heater. The machine head assembly comprises a shell provided with a mounting opening; the electric control box is integrated with a display board, a control board, a relay board and an adapter board and is arranged at the mounting port, and the display board is exposed towards the outside of the shell. According to the machine head assembly, the display board, the control board, the relay board and the adapter board are all integrated in the electric control box, so that the occupied space of the display board, the control board, the relay board and the adapter board in the shell is reduced, the structural compactness of the machine head assembly is improved, and the size of the machine head assembly can be smaller.