26208@aspen-apumedium
DM1 Exhaust Press Snub Plug
refrigeration
Description
An irregular backpressure signal was detected or the signal was lost, and the unit alarms only and starts a regeneration event after every eight hours of APU operation.
Activation Conditions
An irregular backpressure signal has been detected or signal has been lost.
Unit Behavior
Alarm only An open/short circuit may have been detected. A regeneration event will be initiated after every eight hours of APU operation.
Reset Conditions
DPF controller does not sense backpressure when APU is not operating or detects a pressure rise after engine is started. OR Alarm Reset OR Cycle Power
Corrective Actions
1. Verify with backpressure reading in CabinTech. Determine if condition occurs when engine is on or off. 2. Visually inspect wiring to backpressure sensor. 3. Validate backpressure sensor.