Operation 3 - 3
Afterfilter cartridges are NOT interchangeable and
must be installed in their respective assemblies
ONLY. The proper filter cartridge part number is
listed on each Prefilter and Afterfilter Assembly.
3. Replace and tighten filter assembly bowls. Ensure
that O-rings are properly seated.
4. Close any manual vent or drain valves installed in pre-
filter and afterfilter assemblies.
5. If the prefilter assembly was factory equipped with an
automatic drain valve, inspect for, and remove pipe
plug or cap which may have been installed in drain
port for shipping purposes. Ensure isolation ball
valve to automatic drain valve is open.
6. Ensure that all associated pipe and tubing connec-
tions, flanges, unions, plugs, mounting bolts, pipe
hangers, etc., have been checked tight and/or prop-
erly secured.
IMPORTANT: It is recommended that the System's
process gas output not be consumed or used at the
intended points of use until the Start-Up and any re-
lated adjustments have been completed, and the
system is producing process gas of the required
quality. The quality of the process gas should be veri-
fied through test and analysis when a specific quality
process gas is required.
7. Supply compressed air up to System Inlet Isolation
Valve.
8. Energize the dryer’s electrical power supply.
9. Supply pressure to system by SLOWLY opening
System Inlet Isolation Valve (customer-supplied).
Both desiccant chamber Inlet Switching Valves will
open and both chamber Purge Exhaust Valves will
close. The desiccant chambers will immediately be-
gin pressurizing to system pressure as indicated by
chamber pressure gauges.
10. The Moisture Indicator's (if dryer so-equipped) bleed
valve is installed directly into the back of the
indicator's body. Close the Indicator's Bleed Valve.
FULLY open the Moisture Indicator Supply Valve.
11. Soap bubble test all external piping, fittings, and con-
nections. Locate and repair all noted points of leak-
age. Do not soap bubble test components lo-
cated inside dryer control system's enclosure.
Note: Small leaks noted in inlet piping to the dryer
will not affect operation, other than a slight loss of
pressure supplied to the dryer. HOWEVER, any gas
leaks, (no matter how small), detected at, or down-
stream of the dryer outlet MUST BE FIXED to en-
sure that the dryer will provide a continuous supply
of process gas at specified dew point, to intended
points-of-use.
15. Refer to Appendix A (Appendix C for -100°F pdp) of
this manual and calculate your dryer model's purge
pressure setting as instructed.
16. Locate the Purge Adjusting Valve. Slowly rotate
dryer’s Purge Adjusting Valve until the Purge Pres-
sure Indicator indicates the calculated purge pressure
setting. (See following Note).
Note: The purge pressure can only be read and ad-
justed when an off-stream desiccant chamber has de-
pressurized for regeneration. (When the off-stream
chamber is pressurized, the Purge Pressure Indicator
will read “system pressure”.)
17. The Start-Up procedure for models LS60 through
LS1000 is now complete. Proceed to the Normal Op-
eration Checks section of this manual for final opera-
tional checks and adjustments.
3.4 Initial Start-Up For DryersWith DEC Controller
WARNING!
Ensure that the dryer is de-energized, valve isolated
and fully depressurized before attempting to remove
or disassemble any dryer component or subassem-
bly. Failure to do so may result in serious personal
injury and/or equipment damage.
CAUTION: Each component of a Hydrobloc LS Series
Regenerative Desiccant Dryer System has been selected
to compliment the performance of the other components of
the system. Therefore, use of unauthorized parts or sup-
plies or improper operation will degrade system perfor-
mance.
Once the Hydrobloc LS Series Dryer System has been in-
stalled according to instructions, it is ready to be oper-
ated. The system is fully automatic and does not require
any auxiliary controls. It is designed to run continuously.

Dryer Models LS60 through LS1000

Do not start the dryer with compressed air flow through
the dryer. Close customer supplied dryer shut-off valves
before beginning start-up procedure.
1. Refer to the General Arrangement drawing as neces-
sary for component identification and location while
conducting start-up and operational procedures.
Note: If your dryer cannot be started, or fails to start
due to special installation or other problems, contact
your local Deltech Sales Representative for assis-
tance.
2. All Prefilter and Afterfilter Assemblies are shipped
WITH filter cartridges installed. Verify that prefilter
and afterfilter cartridges are installed. Prefilter and