The present invention provides a pump unit including at least one hydraulic pump with inlet and outlet ports, a pump case for accommodating the hydraulic pump having an opening through which the hydraulic pump is insertable, and a lid, called a center section, closing the pump case. A second embodiment includes a box-type sign with a housing having a light-transmitting top panel, a message on both side panels, light-transmitting ends, and either one or two mirrors supported on the bottom angled to reflect light against the messages. By reducing the depth size, the front surface of a cabinet and the front surface of a door 2 can be disposed flush with each other, without having to sacrifice the depth of the heating chamber 6.