Operation; Start-Up And Shut Down Procedures - Gardner Denver RHC Series Instruction Manual

3.0 Operation

3.1 Start-up and Shut down Procedures

A. Pre-start-up Procedure
After making sure Master switch is OFF (Pushed in),
energize dryer. Power on light will illuminate.
CAUTlON: do not turn Master switch to ON at this
time. Dryer must be energized twenty-four (24)
hours before refrigerant compressor is started.
NOTE: Start-up should be done only under the
supervision of a qualified refrigeration mechanic who
is familiar with accepted operational practices for
refrigeration systems.
1. Water-Cooled models - Open main water supply
valve and allow water to flow through the condenser.
Check for water leaks. Water will not flow through
water valve unless head pressure is over 196 psig, 13.8
kgf/cm 2 .
2. Open refrigeration valves
a. Backseat (by turning counterclockwise as far as
possible) hot gas by-pass line manual shut off
valve.
b. Open compressor high side (discharge) service
valve by first back seating (turning counterclock-
wise as far as possible) then (water-cooled models
only) turning clockwise two (2) complete turns.
c. Back seat (by turning counterclockwise as far as
possible) liquid line shut-off valve, then turn
clockwise two (2) complete turns.
d. Back seat (by turning counterclockwise as far as
possible) compressor suction service valve.
e. Refrigerant leak test all refrigerant connections
and refrigeration system components using a
halogen leak detector, General Electric Model H-11
or equal. Pay particular attention to control lines
which may have loosened during shipment or
handling. Refrigerant leaks are normally evidenced
by the presence of oil at the leak.
3. Check compressor for correct oil level. (Oil should be
visible in sight glass).
4. Check electrical voltage to be sure it is within the limits
shown in Technical Data Section or 10% of nameplate
voltage.
5. Check that automatic condensate drain valve isolation
valves are open.
6. Air-Cooled models - Check that any isolation valves
between dryer and condenser are open.
B. Start-Up Procedure - (Dryer energized; master switch
off)
CAUTlON: DRYER MUST BE ENERGIZED (POWER ON
LIGHT ILLUMINATED) TWENTY-FOUR (24) HOURS BEFORE
START-UP OF THE REFRIGERATION COMPRESSOR.
6
1. After dryer has been energized at least twenty-four
(24) hours pull Master switch to on position. Dryer will
automatically pump down. Allow dryer to cycle until
display on Operator Interface indicates Stand-by.
2. Turn Stand-by/Auto Selector Switch to AUTO position.
3. While keeping the air by-pass valve open and air outlet
valve closed, SLOWLY open the dryer inlet valve to
pressurize the dryer.
4. Leak test all air piping, flanges, and drains for possible
air leaks.
5. Air-Cooled Models - Fan(s) in compressor section
should start up after unit has been running for several
minutes. Fan(s) may not start up immediately upon
introducing power to the condensing unit since they
are controlled by means of a refrigerant pressure
switch. This switch may cycle fan(s) off and on in order
to adjust to varying load conditions in refrigerant
system.
IMPORTANT: Air-Cooled Models - Check for proper
fan rotation. Air should be pulled through condenser.
6. After dryer has operated about fifteen (15) minutes,
slowly open the dryer air outlet valve.
7. Close the dryer air by-pass valve.
8. Make a general inspection of the dryer. Tighten all
bolts, nuts, and fittings.
9. Remove all service gauges and test instruments.
Replace all seal caps on valves. Retest connections for
leaks with leak detector.
10. Allow the dryer to operate normally for at least three
(3) hours. Recheck operation of all controls, safety
switches, instrumentation and condensate drains.
11. Review Operational Check Points as listed in
Section 3.5.
C. Standard Shut-Down Procedure
Turn Stand-by/Auto Selector Switch to STAND-BY position.
Allow dryer to operate in this mode during shutdown
period. (Master switch remains in on position).
D. Maintenance Shut-Down Procedure
This procedure is used to shut unit down for extended
maintenance periods.
1. Turn Stand-by/Auto Selector Switch to STAND-BY
position. Allow unit to cycle several times.
2. Push the Master switch to OFF position.
NOTE: Except for maintenance reasons, leave dryer
energized. This allows the crankcase heater to func-
tion.
WARNING: De-energize dryer at disconnect if working
on electrical or rotating components.