A method of distinguishing leak detection and canister disengagement in a reduced pressure treatment system includes monitoring an actual power level and a source pressure of a reduced pressure pump. The actual power level is compared to a target power level, and the source pressure is compared to a first alarm pressure and a second alarm pressure. A leak alarm is indicated when the actual power level is greater than the target power level and the source pressure is greater than the first alarm pressure. A canister disengaged alarm is indicated when the actual power level is greater than the target power level and the source pressure is less than the second alarm pressure.