Parker Airtek TW 770 - Excessive Air Loss on Regenerating Tower; Exhaust Valve on Drying or Repressurizing Tower Leaking; Excessive Pressure Drop; Unit Does Not Fully Repressurize

1. Valve dirty Clean valve
2. Defective diaphragms or O-rings Repair or replace
3. Leaking control solenoid Repair or replace
1. Pre-filter dirty Replace element
2. Afterfilter dirty Replace element
3. Desiccant dirty Replace desiccant
1. Purge rate too low Adjust purge
2. Exhaust valves leaking See above
3. Repressurization solenoid faulty Replace solenoid
1. Clogged mufflers Clean, repair or replace
2. Check valves leaking Clean, repair or replace
3. Purge flow too high Adjust
4. No output from controller Replace fuse or controller
1. Bad diaphragms or O-rings Rebuild valves available kits or replace
2. No control air See below
3. Control solenoids defective Repair or replace
4. No output from controller Repair or replace
1. Control air shutoff valve closed Open
2. Control air filter dirty Replace Element
3. Leak in control air tubing Repair
4. Control solenoid defective Repair or replace
5. No output from controller Replace fuse or controller
2. Dirty or defective control solenoid Clean or replace
Exhaust Valve on Drying or
Repressurizing Tower Leaking
Excessive Pressure Drop
Inlet or Exhaust Valves not
functioning
4. Purge or repressurization orifice
plugged
NOTE - On newer units, orifice is a different
color than the rest of the unit
Unit Does Not Fully
Repressurize
Back Pressure in
Regenerating Tower
Constant Bleed From Vent On
Inlet
1. Defective diaphragms or O-rings Rebuild or replace
No Control Air at Inlet or
Exhaust Valves
1. Associated inlet or exhaust vavle
defective
Rebuild or replaceConstant Bleed From Control
Solenoid Top Exhaust Port