Gardner Denver RDS Series Operation And Maintenance page 11

RDS Series — 50-1000 SCFM
Installing the Dryer
4.1 Piping and Connections Cont.
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
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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
on the control panel.
Water Cooled Unit Operating Instructions
Water-cooled units are designed using 85 Deg F inlet water.
Make the condenser water connections to the dryer
According to the inlet and outlet labels on the inlet and
outlet lines. The water-regulating valve is located on the
inlet line. Unions and isolation valves should be installed on
the inlet and outlet for service and isolation purposes.
N : Water used in water cooled condensers should be
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treated or severe condenser fouling and resulting loss of
heat transfer could occur.
This will greatly affect dryer performance and efficiency.
Units employing water -cooled condensers use a head
pressure controller (water regulating valve) to regulate the
high side pressure of the refrigeration system. The valve has
a capillary tube that is connected to the high side and
measures high side or head pressure. As the pressure
increases, force on a diaphragm inside the valve is increased
causing the valve to open. This action increases water flow
to the condenser, creating more heat removal potential and
lowering the high side pressure. As the pressure drops, the
valve closes and high side pressure is allowed to increase.
By monitoring pressure and adjusting water flow, the valve
regulates the head pressure.
Water regulating valves are set at the factory and do not
normally need any additional adjustment. If for some reason
the unit needs adjustment, use the following procedures.
Temperature procedure
1. Ensure that the dryer is on and operating before making
theses adjustments.
2. Attach the probe of an electronic thermometer or other
temperature sensing device to the outlet water line on the
condenser. Readings must be taken on the Fahrenheit
scale.
(setting the valve using temperature)
3. Place a wrench on the adjusting nut at the top of the
water-regulating valve.
4. Turn the adjusting nut in the direction indicated on the
top of the valve to increase or decrease water flow.
Adjust the nut until the water temperature on the
thermometer reads 105 Deg F with a minimum of
fluctuation.
Pressure procedure
1. Ensure that the dryer is on and operating before
making these adjustments.
2. Install a set of manifold gauges on the high side of the
refrigeration system. There is a Schraeder connection
(access valve) for this purpose.
3. Place a wrench on the adjusting nut at the top of the
water-regulating valve.
4. Turn the adjusting nut in the direction that is indicated
on the top of the valve to increase or decrease water
flow. Adjust the nut until the high side refrigerant
pressure is 225 PSI with a minimum of fluctuation.
REQUIRED WATER FLOW
M #
75
ODEL GPM@
RDS50 0.4
RDS75 0.5
RDS100 0.6
RDS150 0.7
RDS200 0.8
RDS250 1.0
RDS300 1.3
RDS400 1.7
RDS500 2.2
RDS650 2.8
RDS800 3.4
RDS1000 4.4
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Section 4
(Setting the valve using pressure)
80 85
GPM@ GPM@ GPM@
0.5 0.7
0.7 0.8
0.8 1.0
0.9 1.1
1.0 1.2
1.2 1.5
1.6 2.0
2.1 2.6
2.6 3.3
3.4 4.3
4.1 5.2
5.2 6.5
100
2.7
3.3
3.8
4.4
5.0
6.0
7.9
10.3
13.1
17.0
20.6
26.2