A combination light and pressure relief vent (10) is disclosed which includes a housing (11), a valve assembly (12), and a light assembly (13). The housing include a valve body (16), port tube (17), and an outside louver (18). The valve body has a low pressure intake port (25), a high pressure intake port (26), and a low pressure exhaust port (27). The valve assembly includes a low pressure intake valve (40), a high pressure intake valve (42), and a low pressure exhaust valve (44). The light assembly includes a heat sink casing (51) which partially defines a heat chamber (52). The casing has a front wall (55) to which is mounted an LED module (57). A lens cover (61) is coupled to the front surface of the casing. Heat generated by the LED module is transferred through the casing to the heat chamber to warm the valve assembly.