20
Troubleshooting (cont’d)
Problem
Probable Cause
Remedy
High Dewpoint
High inlet air flow
Reduce inlet air flow
Inlet air temperature above
design spec
Reduce inlet air temperature to design spec
Poor pre-filtration
Check pre-filter element, replace if needed
Inlet air pressure below
design spec
Increase pressure to the dryer
Desiccant contaminated
Replace desiccant
Purge flow orifice in the
outlet APV valve may be
clogged
Dismantle outlet APV valve, and clean out the
orifice
Back pressure in
regenerating chambers
Mufflers are clogged, install new mufflers
Exhaust valve(s) not fully
opening or closing
Check pilot valve and pilot air supply,
dismantle and clean exhaust valve, check flow
control valve attached to purge exhaust valve
actuator may not be adjusted properly (should
be adjusted so exhaust valve opens within a
8-12 second time period)
APV valve leaking
Dismantle and clean, replace seals and piston if
needed
No input power
Check that dryer is on with correct voltage
No input power
Check that dryer is on with correct voltage
Controller failure
Check, replace if needed
High-Pressure Drop
Low inlet pressure
Increase inlet pressure to design pressure
Desiccant dusting
High inlet flow velocities due to high flow
Inlet prefilter dirty
Inspect and replace as needed
High inlet flow rate
Reduce inlet flow rate to meet dryer spec
Outlet filter dirty
Inspect and replace as needed
Desiccant diffuser screens
clogged
Inspected and clean if needed
High Back Pressure in
Regenerating Tower
Purge muffler clogged
Clean and replace if needed
Desiccant diffuser screens
clogged
Inspected and clean if needed
Restrictive purge exhaust
piping
Clean and replace with larger pipe if required
Aircel
C
DP-Series Models 70 - 500
