Start-Up And Shut-Down; Hot-Gas Bypass Valve Adjustment - Gardner Denver RDS Series Operation And Maintenance

RDS Series — 50-1000 SCFM
Start Up and Shutdown Procedures
5.0 Startup
BEFORE STARTING THIS DRYER , FOLLOW THE
INSTALLATION INSTRUCTIONS AND
PROCEDURES COMPLETELY.
SERIOUS PERSONAL INJURY CAN RESULT IF
INSTRUCTIONS ARE NOT CAREFULLY AND
COMPLETELY FOLLOWED.
DO NOT REMOVE, REPAIR, OR REPLACE ANY
ITEM ON THE DRYER WHILE THE DRYER IS
UNDER PRESSURE.
Initial Startups
(This procedure should be followed on initial startup and
after preiods of extended shutdown)
1. Confirm that all piping and electrical
connections are proper.
2. If a bypass is installed around the dryer, close the
inlet and outlet isolation valves. Open the bypass
valve.
3. With no pressure or air flow on the dryer, turn the
ON/OFF switch to AUTO. In auto, the dryer will
remain off until the pressure switch senses an
increase in pressure. In manual, the dryer will run
with no air pressure present. Dryers are shipped in
the "AUTO" mode.
4. With valves in position #2, SLOWLY pressurize
the air side of the system by opening the inlet
valve to the dryer. As pressure increases, the
dryer will turn on and begin to run.
5. When the dryer is under system pressure, slowly
open the outlet isolation valve and close the
bypass valve.
6. The system is now on line and will operate
normally. Monitor the dryer to ensure that it is
operating within the proper parameters. At rated
conditions, (100 PSI inlet pressure, 100 Deg F
inlet temperature, and 100 Deg F ambient) the
dewpoint monitor should be in the green area. As
parameters change, the dewpoint will adjust itself
accordingly.

Hot-Gas Bypass Valve Adjustment

If the suction pressure is above (or below) the normal
operating range, adjust as follows (note the suction
pressure will be high if the dryer is overloaded):
Bypass the flow of compressed air around the dryer.
The hot-gas-bypass valve can only be adjusted
accurately with no load on the dryer. Allow 15 minutes
for the dryer to stabilize before making adjustments.
Turn the adjusting screw clockwise to raise the suction
pressure. Turn counter-clockwise to lower the suction
pressure to the normal range.
Open the air bypass valve and close the block valve.
This simple adjustment does not require a trained
refrigeration technician and is not covered under
warranty.
Temperature –Pressure Chart R-22
Temperature (Deg. F)
28
30
32
34
35
36
38
40
45
Shutdown
The side panels of the dryer slide out to allow access for
maintenance. Keep the area directly over the dryer clear
of piping, pipe hangers, or pipe supports so that the
panels can be removed.
N : It is not possible to switch the dryer between
OTE
MANUAL and AUTO modes once it is started in either
mode. To switch the dryer between modes, use the
following procedure.
1. Turn the dryer off at the "STOP" switch on the font
control panel.
2. De-energize the dryer from the main power source.
3. Toggle the MANUAL / AUTO switch to the
desired mode.
4. Re-apply the power to the dryer.
5. Turn the dryer on by depressing the "on" button
- 15 -
Section 5
Pressure (PSIG)
52.4
54.9
57.5
60.2
61.5
62.9
65.7
68.6
76.1