3 - 4 Operation
IMPORTANT: Water molecules can diffuse through
a pinhole-size leak even though pressure inside the
piping is several hundred PSIG. It is not uncommon
to have a minute pinhole leak in a gas line cause an
increase in dew point from -40°F to -10°F at a dis-
tance of forty or more feet downstream of the leak.
12. SLOWLY open the customer-supplied System Out-
let Isolation Valve, while monitoring the Outlet Pres-
sure Gauge (if dryer so-equipped). DO NOT permit
the Dryer's Outlet Pressure Gauge to exceed a 5%
drop in pressure while pressurizing downstream pip-
ing.
13. Close the customer-supplied System Bypass Valve
(if installed).
14. Open and adjust the Moisture Indicator’s Bleed
Valve until a very slight, continuous gas bleed is felt
exhausting from the bleed valve’s exhaust port. En-
sure that the granular indicator crystals remain mo-
tionless after final adjustment.
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
depressurized for regeneration. (When the off-stream
chamber is pressurized, the Purge Pressure Indicator
will read “system pressure”.)
For dryers with the Hydrobloc Compu-Save Energy
Management System: During operation in the Energy
Management Mode, the off-stream chamber may re-
main pressurized (in ENERGY MANAGEMENT AC-
TIVE). If this condition is noted, proceed as follows to
adjust purge pressure.
a) Open Dryer Control System Enclosure. Locate
DIP switches on MEC CPU Board.
b) Switch DIP switch position 7 to OFF position
(down). De-energize dryer’s electrical power sup-
ply for approximately fifteen (15) seconds; then
re-energize. Dryer is now in Fixed Cycle Opera-
tion. The off-stream chamber will depressurize to
atmosphere for regeneration.
c) Calculate and set purge pressure as previously
instructed.
d) Return DIP switch position 7 to ON position.
De-energize the dryer’s electrical power supply
for approximately fifteen (15) seconds; then re-
energize. Dryer should be in Compu-Save En-
ergy Saver Mode.
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.
Dryer Models LS1250 and LS1500
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
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. Open the Pilot Gas Supply Valve, located upstream
of the Pilot Gas Filter.
9. Supply pressure to system by slowly opening the
System Inlet Isolation Valve (customer supplied).
The Inlet Switching Valve will open to either left or