Pneumatech EE Series, Owner'S Manual

24

Pub. No. OM-A-10E — April 2004

D. Excessive flow through mufflers.

1. Check valves leaking.

NOTE: 

To test for leaking, check valves 

during regeneration cycle, shut the 
purge adjusting valve. If gas is still 
passing through, it is an indication of 
leaking check valves.

2. Inlet valves did not switch.
3. Purge valve stays open.

4. Repressurizing valve does not 

close.

5. Diaphragms ruptured in valves 

(EE models).

1. Repair or replace faulty check 

valves.

2. See F1 to F4.
3. Check purge solenoid and valve. 

Repair or replace faulty purge 
valve or solenoid.

4. Check repressurizing solenoid 

and valve. Repair or replace faulty 
repressurizing valve or solenoid.

5. Replace diaphragms.

E. No gas flow through the dryer.

1. Both inlet valves closed due to low 

inlet pressure.

1. Manually open the inlet valve by 

turning the shaft or the ON 
actuator.

F. Failure to switch alarm light.

1. Inlet valves did not switch.

2. Faulty timer.
3. Insufficient pilot air pressure.

4. Cylinder leaking or seized up.

1. Check pilot air solenoid valve. 

Repair if necessary.

2. Replace timer.
3. Clean or replace pilot filter 

element.

4. Repair or replace pilot air 

cylinder.

G. High pressure drop in dryer.

1. Desiccant retainer screens 

plugged.

2. Excess flow.
3. High purge flow.
4. Purge valve stays open.

5. Repressurizing valve stays open.

1. Replace desiccant retainer 

screens.

2. Check inlet flow conditions.
3. Check and reset purge pressure.
4. Check repressurizing solenoid 

valve, repair or replace if 
necessary. Check timer.

5. See D4.

H. Dryer fails to purge.

1. Orifice plate plugged.
2. Purge valve fails to open.
3. Purge valve closed.
4. Purge check valve blocked.

1. Clean the orifice plate.
2. See G3.
3. Reset proper purge pressure.
4. Inspect purge check valve. 

Replace if necessary.

I. High dewpoint alarm light.

See chart on alarm conditions.

J. Moisture indicator color turned pink 

(wet conditions).

1. Bleed valve closed.
2. See probable cause on #1.

1. Open the bleed valve to allow 

small amount of air to constantly 
flow through the gel.

K. Tower fails to pressurize.

1. Purge valve stays open.
2. Repressurizing valve faulty.
3. Diaphragms ruptured in valves 

(EE models).

1. See G3.
2. See D4.
3. Replace diaphragms.

Table 1 — Troubleshooting Guide for Regenerative Dryers, continued

Symptoms

Cause

Remedy