A-8
“Oil-Less” Scroll Laboratory Air
4107 9006 25.11
Appendix A: Desiccant Dryer
A.5 Replace/Repair
WARNING:
Ensure that the dryer and associated
pre-fi lter(s) and afterfi lter(s) are valve
isolated and fully depressurized before
attempting to remove or disassemble any
subassemblies or components. Failure to
do so may result in serious personal injury
and/or equipment damage.
A.5.1 Desiccant Replacement Procedure
WARNING:
Used desiccant material must be handled
with special care. Desiccant is an
adsorbent material. Used desiccant may
contain chemicals and/or gases that are
hazardous, toxic and/or fl ammable. It is
recommended that all used desiccants
be analyzed to determine content before
disposal. Exercise proper care and
procedures during handling and storage
of used materials. All containers must
be properly labeled and disposed of in
accordance with local, state and federal
regulations.
1. Shut down dryer – close the inlet and outlet
isolation valves and turn off electrical power to
the dryer.
WARNING:
Desiccant towers contain springs which
may release potential energy upon
dismantle.
2. Remove hex nuts, washers and towers from
manifold assembly.
3. Remove spring and perforated screen from top
of canister.
4. Remove canister from manifold assembly,
being careful not to spill any desiccant.
5. Dispose of used desiccant into suitable
containers.
6. Remove any blockage that may have lodged in
the perforated screens.
7. Replace canister O-rings. Set canister onto
manifold assembly.
8. Install the perforated screen into the bottom
of the canister.
9. Fill canisters with desiccant to one inch (1”)
from the top of canister. Install perforated
screen.
CAUTION: DO NOT OVERFILL
10. Set spring retainer on top of perforated screen.
Install tower over the canister. Install plain
washers and hex nuts. Tighten nuts in an
X-pattern until chambers are snug against the
manifold. Torque to 35 ft-lbs.
A.5.2 Check Valve Replacement Procedure
1. Remove the caps/plugs from the underside of
the dryer block. See Figure A.3.
2. Using a 1⅛ deep well socket, remove the check
valves.
3. Replace check valve and cap/plug in dryer
block.
Figure A.3 Dryer Block Check Valves
