Illustrative embodiments of new and useful systems and methods for reduced-pressure therapy are described. One example embodiment is a manually-actuated pump for applying reduced-pressure therapy. The pump generally comprises a charging chamber, a regulated chamber, and a regulator passage between the charging chamber and the regulated chamber. A valve body controls fluid communication through the regulator passage, and a regulator spring may be engaged with the valve body to bias the valve body against a differential between a pressure in the regulated chamber and an ambient pressure. The regulator passage may have a bore size adapted deflect the valve body to cause an audible indication of a leak.