Concoa 621 Series User manual

621 Series
Autoswitch
System
For use with
Laser Purity Gases
INSTALLATION AND OPERATION INSTRUCTIONS
Before Installing or Operating, Read and Comply with These Instructions
Controls Corporation of America
1501 Harpers Road Virginia Beach, VA 23454
To Order Call 1-800-225-0473 or 757-422-8330 • Fax [phone]
www.concoa.com
September 2003
Supersedes May 2003
Certied ISO 9001
ADI 3199D
®

3
THIS PAGE INTENTIONALLY LEFT BLANK

3
XXX Series
DESCRIPTION OF PRODUCT
The 621 Series autoswitch is an automatic switchover system designed to provide a continuous supply of laser purity
gas. This unit may be used with one cylinder per side, or used with a manifold that has increased storage capacity.
The inlet of the switchover system may be congured with open ports, diaphragm valves, manifold connectors, or
exible pigtails. The system, when congured with manifold connectors, is for use with the 528 Series Maniex
system. The standard autoswitch system will maintain a regulated line pressure within the values shown in the table
below:
This model can be congured to be used in conjunction with an optional Remote Alarm. It cannot be connected
directly to AC line voltage. In addition to a Power Indicator light, the autoswitch is equipped with LED status
lights to indicate the condition of the gas cylinders. A green indicator light signies a “Normal” condition while a
red light indicates an “Alarm” (Gas cylinder empty) condition. The autoswitch system includes a separate connector
that mates to the connector on the bottom of the unit. This will be needed to construct an interface cable between
the Remote Alarm and the autoswitch. Please refer to the ADI Manual that is included with the Remote Alarm for
wiring and operating instructions.
Line Regulator
Adjustment Knob
Inlet Gauge
Inlet Port
1/2” NPT Female
Delivery Gauge
Inlet Port
1/2” NPT Female
Inlet Gauge
Priority Valve
Outlet Port
1/4” Tube connection
Figure 1
MODEL RANGE
621 3XXX 0-100 PSI (0-7 BAR)
621 5XXX 0-350 PSI (0-24 BAR)
621 7XXX 0-150 PSI (0-10 BAR)
The inlet pressure must be maintained above the value listed in the table below for the system to operate properly.
MODEL RANGE
621 3XXX 265 PSI (18 BAR)
621 5XXX 540 PSI (37 BAR)
621 7XXX 265 PSI (18 BAR)

4 5
INTENDED USE OF PRODUCT
The brass 621 Series autoswitch system is intended for use in laserpurity, non-corrosive applications. Please note
the safety information shown in the later sections.
USER RESPONSIBILITY
The User of this equipment should follow all labeling, installation and operation instructions when using this
equipment. It is recommended that the user review all safety precautions listed in the safety section of this manual.
Know the properties and special handling requirements of the gas being used. Many gases are dangerous (ammable,
toxic, corrosive , etc.) Consult with the cylinder distributor for the proper use of the cylinders and any restrictions in
their use. This equipment must be checked periodically. Improperly working equipment should not be used. Broken,
worn, distorted, contaminated, or missing components should be replaced by a trained technician immediately.
CUSTOMER ASSISTANCE
In the event of equipment failure, call the CONCOA Customer Assistance Line: 1-800-225-0473. Please be prepared
to provide the model number and serial number of the equipment involved, in addition to some details regarding its
application. This would include inlet and outlet pressures, ow rate, environmental conditions, and gas service.
SAFETY
Carefully read and comply with these instructions before installing or operating any high pressure gas manifold. These
manifolds are designed, manufactured, and tested to conform to industry standards for safety for high pressure gas
manifolds for maximum inlet pressure of 3000 pounds per square inch (200 bar), working pressure.
Always observe the following safety practices:
√ Store cylinders with valve caps screwed on, and cylinders chained to a supporting wall or column.
√ Handle cylinders carefully and only with valve caps screwed on. The cap will prevent the cylinder valve
from breaking off at the top of the cylinder if the cylinder is accidentally dropped or falls over. The cap also
protects the cylinder valve from damage to screw threads, which could cause leaky connections.
√ Due to the highly combustible nature of hydrogen, methane, ethylene and fuel gases, all manifolds used
with this gas are provided with ashback arrestors to stop any burning gas in the pipeline from getting back
to the manifold or cylinders. Flashback arrestors are either water lled or dry check valve type. Gas owing
from the regulators on the manifold ows through the ashback arrestor to the pipeline. Also, arrestors on
pigtails are required for acetylene service.
√ Keep all cylinders away from any source of high temperature (not over 120° F, 50° C) or possible re hazards.
High-pressure gas contained in a closed cylinder becomes increasingly dangerous when exposed to high
temperature because pressure increases and the strength of the cylinder decreases.
√ No smoking should be permitted near oxygen, nitrous oxide, ammable gases and ammable mixtures and
in area where cylinders are stored.
√ Where oxygen or nitrous oxide is used, the manifold and cylinders must be kept clean. No oil, grease, or
combustible substances should come in contact with oxygen or nitrous oxide storage or handling equipment.
Such materials in contact with oxygen or nitrous oxide are readily ignitable and when ignited, will burn
intensely.
√ Never lift gas cylinders with a magnetic lifting device.

4 5
√ Never use an open ame when leak testing.
√ Always open valves slowly when high-pressure gases are being used. Open valves all the way.
√ Always be sure that a cylinder contains the correct gas before connecting it to any manifold.
√ Always leak-test any manifold or distribution pipeline before using.
√ Always be sure that the gas in a pipeline is the correct gas for the intended use.
√ Always install a blind gland and nut or piping plug on any manifold inlet tting if no cylinder is connected
to the tting before opening any cylinder valve which is already connected to the manifold.
√ Always close all cylinder valves before disconnecting cylinders from a manifold.
√ Always remove all empty cylinders from a manifold before connecting full cylinders.
√ Always test cylinders to be sure they are full before connecting to a manifold.
√ NOTE: Use of Teon® lined pigtails for oxygen installations is not recommended unless they are equipped
with a Distance Volume Piece (DVP). Components in the manifold system can create a dead end passage.
The combination of a dead end passage coupled with a rapid pressurization may lead to adiabatic compression
of the contained oxygen and subsequent failure of the pigtail by ignition.
√ All gas distribution piping systems must meet appropriate industrial standards for the intended service, and
must be thoroughly cleaned before using.
Comply with all safety rules and precautions of the following:
1. American National Standards Institute standard Z49.1 or Safety in Welding and Cutting, American Welding
Society, 2501 NW Seventh Street, Miami, FL 33125.
2. N.F.P.A. Standard 51, Oxygen-Fuel Gas Systems for Welding and Cutting, N.F.P.A., 470 Atlantic Avenue,
Boston, MA 02210.
3. N.F.P.A. Standard 51B, Cutting and Welding Processes, (see Address in #2)
4. CONCOA Publication ADE 872, Safety Precautions in Welding and Cutting.
5. Local ordinances.
6. O.S.H.A.
7. C.G.A. Pamphlet C-4, American National Standard Method of Marking Portable Compressed Gas Containers
to Identify the Material Contained.*
8. C.G.A. Pamphlet G-4, Oxygen-Information on the properties, manufacture, transportation, storage, handling,
and use of oxygen.
9. C.G.A. Pamphlet G-4.1, Equipment Cleaned for Oxygen Service.
10. C.G.A. Pamphlet C-4.4, Industrial Practices for Gaseous Oxygen Transmission and Distribution Piping
Systems.
11. C.G.A. Pamphlet G-5, Hydrogen - Information on the properties, manufacture, transportation, storage,
handling, and use of hydrogen.
12. C.G.A. Pamphlet G-6, Carbon Dioxide - Information on the properties, manufacture, transportation,
storage, handling, and use of carbon dioxide.
13. C.G.A. Pamphlet G-6.1, Standard for Low Pressure Carbon Dioxide Systems at Consumer Sites.
14. C.C.A. Pamphlet P-1, Safe Handling of Compressed Gases in Containers.

6 7
INSTALLATION
The site chosen for the installation of the system shall be level, well ventilated, and at a safe distance from sources of
ames, sparks, and excessive heat. The system should not be placed in an area that may subject it to damage from
passing trucks, cranes, or other heavy machines. Any oxygen system must not be installed under shafting, belting,
or other places where oil can drip on it. Refer to the Manifold ADI for Manifold installation instructions.
a. Be sure to consider all factors when selecting materials.
b. Do not use oil or grease on ttings.
c. Be sure that all ttings are secure and leak tight. Teon tape should be used on pipe threads. See Figure 6.
d. Relief valve: The purpose of the relief valve is to protect the autoswitch system and its components only
(Figure 2). If there is pressure sensitive equipment downstream of the autoswitch system, it is recommended
that an appropriately sized relief valve be installed in the line to protect this equipment.
e. Purge devices: These devices can be purchased as accessories. Purge devices are used to remove toxic, corrosive,
or ammable gases from the customer’s system to a safe discharge area. This is particularly helpful when an
internal problem occurs (such as regulator malfunction).
WARNING: Equipment failure or misuse may lead to problems such as a release of gas through the relief
valve or regulator diaphragm. The autoswitch box is not sealed and will leak gas from faulty components.
Proper safety measures should be established to handle these and other component failures.
Relief Valve Remote Alarm Connector
Figure 2

6 7
WALL MOUNTING
Follow Compressed Gas Association, OSHA and all applicable local codes. Manifolds should not be placed in
locations where the temperature will exceed 102°F (49°C) or fall below 0°F (-18°C). Manifolds installed in open
locations should be protected from weather conditions. During winter, protect the manifold from ice and snow. In
summer, shade the manifold and cylinders from continuous exposure to direct sunlight. Always leave access to the
manifold for cylinder replacement.
1. Determine and mark the vertical center line for installation of the AutoSwitch Console. (Figure 3).
2. Measure from the oor 73” in height* of this center line. This height will place the manifold header
approximately 66” from the oor. Using a level, mark a horizontal line at this point extending
approximately 10 inches to the left and right of center.
3. Remove the mounting bracket from the rear of the AutoSwitch Console by removing the retaining nuts at
the bottom of the mounting bracket (Figure 5). Place the upper edge of the bracket cross-member on the
horizontal line so that it is centered with the vertical line. Holding the bracket with the slotted extensions
away from the wall, mark the location of the two mounting bolts (Figure 4)
4. Using appropriate hardware based on wall construction, anchor the mounting bracket to the wall (Figure
4).
5. Place the autoswitch system so that the mounting bracket slots align with the shoulder nuts. With the
autoswitch box hanging on the shoulder nuts, align the retaining bolts so that they protrude through the
bracket. Replace the mounting nuts that were removed in step 3.
Figure 3 - Center-line Mark Figure 4 - Mounting Bracket
Figure 5 - Console and Mounting
Bracket
Mounting Bracket
Retaining nuts
Console
Mounting Screws
Shoulder Nuts

8 9
Figure 6 - Pictorial view of tape seal
installation
INLET AND OUTLET CONNECTIONS
General:
Use an open-end wrench, not a pipe wrench, to install accessories to the autoswitch system. ALWAYS hold the
bulkhead tting with a wrench when installing the accessories to the autoswitch system. Do not allow the bulkhead
tting to turn; otherwise, connections inside the box may be loosened. NPT connections require the use of Teon
tape on the threads to make a gas tight seal. (See Figure 6.) On stainless steel connections, the thread sealant helps
prevent the connections from galling together when tightening or loosening. CONCOA uses Teon tape on all of
its NPT connections. Follow these rules when using Teon tape.
Inspect the NPT threads and if necessary, clean the tting to remove any dirt or thread sealant that remains on the
threads. Start the Teon tape on the second thread as shown in Figure 6; make sure the tape does not overlap the
end of the tting. As the tape is wrapped in the direction of the thread spiral, pull tightly on the end of tape so that
the tape conforms to the threads. Wrap the tape around the threads twice. Cut off the excess tape and press the end
rmly into the threads.
Installing the inlet connection:
For Maniex Manifold system installation:
System 621 X12X-CGA (typical manifold setup with the manifold connector) – see Figure 7 for locations of
components:
1. Tape the male NPT connections on the manifold connector using the procedure outlined above in Figure
6.
2. After taping the male NPT connections, thread the  NPT of the manifold connector into the bulkhead
connector of the autoswitch as shown in Figure 7. Wrench-tighten.
3. Remove the tube tting from the opposite end of the manifold connector. The tube-tting nut and body
hex must each be held with a wrench when loosening the tube tting.
4. Thread the  NPT connection of the tube tting just removed into the starter block of the manifold as
shown in Figure 7. Wrench-tighten.
5. Insert the tube tting of the starter block into the pre-swaged tubing of the manifold connector as shown in
Figure 7. While holding the hex of the tube-tting nut and body hex, rotate the wrench until a signicant
increase in torque is felt; after the increase is felt, tighten slightly. Note: do not use the gap inspection gauge
to verify proper tting makeup; the tube ttings on the manifold connector are pre-swaged at the factory.

8 9
System 621 X21X-CGA (typical manifold setup with the manifold connector and diaphragm valve) – see Figure 8
for locations of components:
1. Tape the male NPT connections on the manifold connector and diaphragm valve using the procedure
outlined on page 8.
2. After taping the male NPT connections, thread the  NPT of the manifold connector into the bulkhead
connector of the autoswitch as shown in Figure 8. Wrench-tighten.
3. Remove the tube tting from the opposite end of the manifold connector. The tube-tting nut and body
hex must each be held with a wrench when loosening the tube tting.
4. Thread the  NPT connection of the tube tting just removed into the diaphragm valve as shown in Figure
8. Wrench-tighten.
5. Thread the  NPT connection of the diaphragm valve assembly into the starter block as shown in Figure
8. Wrench-tighten.
6. Insert the tube tting of the starter block assembly into the pre-swaged tubing of the manifold connector
as shown in Figure 8. While holding the hex of the tube-tting nut and body hex, rotate the wrench until
a signicant increase in torque is felt; after the increase is felt, tighten slightly. Note: do not use the gap
inspection gauge to verify proper tting makeup; the tube ttings on the manifold connector are pre-swaged
at the factory. The proper torque must be applied to ensure a leak tight tting.
Figure 7 - Manifold Connector for Maniex Header shown with
two cylinders per side.

10 11
Figure 8 - Manifold Connector with Master Valves shown with one
cylinder per side.
System 621 X72X-CGA (typical manifold setup with the manifold connector) – see Figure 9 for locations of
components:
1. Tape the male NPT connections on the manifold connector, diaphragm valve, and tee purge using the
procedure outlined on page8.
2. After taping the male NPT connections, thread the  NPT of the manifold connector into the bulkhead
connector of the autoswitch as shown in Figure 9. Wrench-tighten.
3. Remove the tube tting from the opposite end of the manifold connector. The tube-tting nut and body
hex must each be held with a wrench when loosening the tube tting.
4. Thread the  NPT connection of the tube tting just removed into the diaphragm valve as shown in Figure
9. Wrench-tighten.
5. Thread the  NPT connection of the diaphragm valve assembly into the tee purge as shown in Figure 9.
Wrench-tighten.
6. Thread the  NPT connection of the tee-purge assembly into the starter block of the manifold as shown
in Figure 9. Wrench-tighten.
7. Insert the tube tting of the starter block assembly into the pre-swaged tubing of the manifold connector
as shown in Figure 9. While holding the hex of the tube-tting nut and body hex, rotate the wrench until
a signicant increase in torque is felt; after the increase is felt, tighten slightly. Note: do not use the gap
inspection gauge to verify proper tting makeup; the tube ttings on the manifold connector are pre-swaged
at the factory. The proper torque must be applied to ensure a leak tight tting.

10 11
Figure 9 - Tee Purge and Diaphragm Valve with Manifold Connector
for Maniex Header shown with two cylinders per side.
For non-manifold system installation:
System 621 X01X-CGA (one pigtail per side) – see Figure 10 for locations of components:
1. Tape the male NPT connections on the pigtail assembly and street elbow assembly using the procedure
outlined on page 8.
2. After taping the male NPT connections, thread the  NPT of the street elbow assembly into the bulkhead
connector of the autoswitch as shown in Figure 10. Wrench-tighten.
3. Thread the  NPT connection of the pigtail assembly into the street elbow assembly as shown in Figure
10. Wrench-tighten. Note: while tightening the pigtail assembly into the street elbow assembly, a second
wrench must be in place holding the hex on the street elbow assembly. Failure to do so may cause the street
elbow assembly to loosen.
System 621 X31X-CGA (one pigtail per side with diaphragm valves) – see Figure 11 for locations of components:
1. Tape the male NPT connections on the pigtail assembly and diaphragm valve assembly using the procedure
outlined on page 8.
2. After taping the male NPT connections, thread the  NPT of the diaphragm valve assembly into the
bulkhead connector of the autoswitch as shown in Figure 11. Wrench-tighten.
3. Thread the  NPT connection of the pigtail assembly into the diaphragm valve assembly as shown in Figure
11. Wrench-tighten. Note: while tightening the pigtail assembly into the diaphragm valve assembly, a
second wrench must be in place holding the diaphragm valve. Failure to do so may cause the diaphragm
valve assembly to loosen.

12 13
Figure 10 - 1/4" FPT Port with one cylinder per side.
Figure 11 - Diaphragm Valve with 1/4" FPT
Port shown with one cylinder per side.

12 13
Figure 12 - Tee Purge and Diaphragm Valve with 1/4"
FPT Port shown with one cylinder per side.
System 621 X61X-CGA (one pigtail per side with diaphragm valves and tee-purge assembly) – see Figure 12 for
locations of components:
1. Tape the male NPT connections on the pigtail assembly, diaphragm valve assembly, and tee-purge assembly
using the procedure outlined on page 8.
2. After taping the male NPT connections, thread the  NPT of the diaphragm valve assembly into the
bulkhead connector of the autoswitch as shown in Figure 12. Wrench-tighten.
3. Thread the  NPT connection of the tee-purge assembly into the diaphragm valve assembly as shown
in Figure 12. Wrench-tighten. Note: while tightening the tee-purge assembly into the diaphragm valve
assembly, a second wrench must be in place holding the diaphragm valve. Failure to do so may cause the
diaphragm valve assembly to loosen.
4. Thread the  NPT connection of the pigtail assembly into the tee-purge assembly as shown in Figure 12.
Wrench-tighten. Note: while tightening the pigtail assembly into the tee-purge assembly, a second wrench
must be in place holding the hex of the tee-purge. Failure to do so may cause the tee-purge assembly to
loosen.
Connecting to a cylinder:
1. Before removing the cylinder cap, move the cylinder of gas to the work site:
a. Secure cylinder to the floor, wall, or bench with appropriate chain, strap, or stand to prevent
toppling.
b. Remove the cylinder cap.
c. Be sure the cylinder valve is tightly closed (clockwise)
d. Remove the cylinder valve plug, if any.
e. Inspect the cylinder valve and threads for damage or contamination.

14 15
2. Secure the cylinder connection to the cylinder in the following manner:
a. Do not force. Tightening the nut onto the cylinder connection should be easy. If it is not, the connection
may be wrong for the type of gas being used.
b. Left-hand threads are used on some cylinder connections. A notch in the middle of the hex nut typically
indicates a left-hand thread.
c. Gaskets are used on some inlet connections. Be sure the gasket is in good shape. Do not over-tighten to
avoid squashing the gasket into the gas line. Keep extra gaskets on hand.
d. Never use oil or grease on regulator or cylinder ttings, as it may contaminate pure gases, or create a re
hazard.
Installing the Outlet Connection:
The autoswitch system has the outlet connection at the top of the box. The connection is a ” tube connection. Connect
tubing to the autoswitch that is compatible with the application and is capable of handling the pressure required.
Pressurizing the system for the rst time (non-manifold use):
Before system startup, it is recommended that all systems be pressure tested, leak tested, and purged with an inert gas
such as nitrogen. To accomplish this with connections other than a CGA 580, it will be necessary to use an adapter.
The recommended use of an adapter is for temporary use only, for system start up and checks. Adapters should never
be used on a permanent basis.
1. Wear safety glasses and gloves.
2. Be sure that both ends of all hoses or pigtails are secured before pressurizing. Turn the line regulator knob
counterclockwise until the knob stops turning.
3. When rst pressurizing, do not stand in front of or contact the switchover system. Slowly open the cylinder
valve. Observe the high pressure gauge for a rise in pressure up to full cylinder pressure.
4. Keep the hand wheel or wrench on the open cylinder valve at all times, to allow prompt emergency shut-
off.
5. Inspect all connections for leaks and x any leaks. A leak detection solution may be applied to the connections
(if compatible with the application) which indicates leaks by bubbling. To further check for leaks, or if the
leak detection solution can not be used, close the cylinder valve for a period of time (recommended 24 hours),
and observe the high pressure gauge for a drop in pressure. If so indicated, recheck the CGA connection and
all other high-pressure port connections. Never attempt to x a leak under pressure. If leaks are detected,
depressurize the system and retighten the connection. Begin again at step 3.
WARNING: While CONCOA assembles the autoswitch system components to exacting leak-tight standards,
the customer should also inspect for any loosening of internal parts that may occur in shipping or installation by
completing the pressure decay test detailed above. If all external leaks have been found, corrected, and the system
still indicates a leak, disassemble the front cover from the autoswitch after removing the eight screws shown below.
Check for leaks on the system’s ttings as described above.
6. Slowly turn the line regulator knob clockwise. This will increase the pressure of the line. Adjust to the desired
working pressure and again check for leaks using the methods described above. See Figure 13.

14 15
XXX Series
Screws
Screws
Screws
Screws
Figure 13
OPERATION
The arrow on the priority valve always points to the primary side; the bank opposite the primary side is considered
the reserve side. Starting with the arrow pointing to the right side, gas will ow from the right side cylinder. As the
gas in the primary side is depleted, the gas pressure will drop on the right gauge. When the inlet pressure drops to
the pressure setting of the reserve side regulator, ow will begin from the reserve cylinder; the inlet pressure on the
primary side will also stabilize. This is called a changeover. At this point, the gas pressure on the reserve side (preset
regulator) will drop. This indicates that its time to change the cylinders on the primary side. Before removing the
nearly depleted primary cylinder, the priority valve should be rotated 180°. This makes the reserve cylinder, the
primary source. Remove the depleted cylinder and replace with a full cylinder. Before removing the cylinder be
sure to close the cylinder valve and any other valves that connect the cylinder to the system. The full, replacement
cylinder is now the reserve cylinder. Note: while changing cylinders on one side, there will be no interruption in
ow. A depleted cylinder will have the following gas pressure remaining:
MODEL RANGE
621 3XXX 195-265 PSI (13.5-18.5 BAR)
621 5XXX 440-540 PSI (30.5-37 BAR)
621 7XXX 195-265 PSI (13.5-18.5 BAR)
Gas will continue to ow from the primary side until the outlet pressure of the preset regulator matches the pressure
of the priority valve regulator. (The pressure setting of the priority valve regulator changes when the knob is turned
180°). When the gas pressure stops dropping on the preset regulator and starts to drop on the priority valve regulator,
it is time to change the left cylinder. The knob is rotated 180° to the right before the left cylinder is changed. It
is helpful to maintain a log of cylinder pressure, noting which direction the arrow is pointing on the priority valve.
When the pressure gauge is very low and the reserve side indicates that gas has begun to ow from the reserve cylinder,
it is time to rotate the knob and attach a full cylinder in reserve.

16 17
If the knob is not rotated before the empty cylinder is changed, two things can happen. First, gas may ow from
the changed cylinder to the existing cylinder. This is because the pressure setting of the regulator on the primary
side allows the regulator main valve to remain open. Second, when the cylinder is changed, gas will begin to ow
from the new cylinder, stopping ow from the existing cylinder. This means the existing cylinder may be partially
empty. After several cycles, it is possible that the reserve cylinder may empty shortly after a switchover occurs. Always
remember to rotate the knob on the priority valve regulator before changing a depleted cylinder.
Adjusting the alarm set point, does not affect the switchover point of the autoswitch. The alarm is used to provide
an audible and visual warning that a changeover is about to occur. If the nearly depleted cylinders are changed when
the alarm LED’s illuminate, the cylinders will not be as empty as if the actual changeover had occurred. Slide the red
tab seen on the inlet gauge to adjust the alarm set point. The lowering of the alarm set point pressure may cause the
alarm not to work properly. When adjustments are made, check the function of the system. With the knob arrow
turned fully clockwise, pressurize the system and shut off the inlet pressure to both sides. Allow the inlet pressure
on the right side to decrease by allowing a small ow (50 CFH). Observe both inlet gauges. When the right bank
is low (below the set point on the gauge), the red LED will illuminate. Make sure the red LED illuminates before
the pressure on the opposite side starts to decrease. Re-pressurize system and check the opposite side of the system
in the same manner (the knob arrow must be turned fully counter-clockwise).
XXX Series
Inlet Gauge:
Red Tab indicates alarm setpoint.
(typical both sides)
Figure 14
MAINTENANCE
On regular intervals, the system should be checked for leaks and proper function (see trouble shooting). Any leaks
in the system should be corrected immediately. The pigtail check valve should also be checked for leaks when a
depleted cylinder is removed. Note: the system inlet and pigtail should be pressurized when checking for leaks. At
no time should the preset regulator’s or priority valve regulator’s pressure settings be changed.

16 17
TROUBLESHOOTING
Symptom Cause
1. Gas leakage at the line regulator outlet when the
adjusting knob of the line regulator is completely
backed out.
2. With no ow through the system (downstream
valves closed and adjusting screw in) line pressure
steadily increases above set pressure.
3. Gas leakage from spring case (adjusting screw/
knob end of regulator).
4. Gas leakage from any joint.
5. Excessive drop in working pressure with regulator
owing gas.
6. Gas leakage from relief valve.
7. Gas leakage from any gauge.
8. Gauge does not return to zero when not under gas
pressure.
9. Gauge does not consistently repeat the same
reading.
10. The system makes a noise or hums.
1. Regulator(s) have malfunctioned. Replace or
repair.
Symptom Cause
1. Switchover system seems to be using gas from
the primary and reserve cylinders (pressure is
decreasing on both inlet gauges at the same time).
1. Make sure the priority valve knob is turned fully
to the right or left.
2. Observe the inlet pressure. It may be necessary
to do this during times of the heaviest use. If the
inlet pressure is less than the values listed below,
replace the high pressure cylinders.
621 3XXX 265 PSI (18 BAR)
621 5XXX 540 PSI (37 BAR)
621 7XXX 625 PSI (18 BAR)
If liquid cylinders are used and the inlet pressure
increases signicantly when the system is not
in use, then the system is over-withdrawing the
liquid cylinders. Additional capacity may be
added to the system to prevent this.
1. Inlet gauges not reading pressure. 1. Check that the valves on the cylinders are opened.
2. If using a manifold system, check that the valve on
the manifold is opened.
1. Power light is not on. 1. Check that connector to remote alarm is properly
plugged into the autoswitch and the alarm.
2. Check that the remote alarm is powered on.
3. Check that cable between autoswitch and remote
alarm is wired correctly.

18
TROUBLESHOOTING (Continued)
Symptom Cause
1. Status lights are not lighted. 1. Check that connector to remote alarm is properly
plugged into the autoswitch and the alarm.
2. Check that the remote alarm is powered on.
3. Check that cable between autoswitch and remote
alarm is wired correctly.
1. Green status light(s) are lighted when the pressure
is below the set point on the gauges.
2. Red status light(s) are lighted when the pressure is
above the set point on the gauges.
1. Cable to remote alarm wired incorrectly. Follow
instructions in remote alarm ADI to correct
problem.
1. With full tank pressure, red alarm light(s) are on. 1. Check that the setpoint on the gauges is set
properly.
SERVICE
A Unit that is not functioning properly should not be used and should be returned to CONCOA for service. A
Return Material Authorization (RMA) number must be issued for any product returned to CONCOA for service.
Please contact a Customer Service Representative at 1-800-225-0473 to receive this number. You will be asked to
provide:
1. Model Number
2. Gas Service
3. Inlet pressure and type of gas supply
4. Outlet pressure
5. Approximate gas usage.
When shipping product back to CONCOA for repair the following steps should be followed:
1. Package the product sufciently to prevent damage. If possible return product in its original packing.
2. Include RMA number on the outside of the carton.
3. Ship prepaid.
4. Include a written description of the problem you encountered with the product inside the package.
5. Include a statement of the gas service the product was used in.
6. Purge all equipment before shipping to protect the transporter and service personnel. Purging is especially
important if the equipment has been in hazardous or corrosive gas service.
CONCOA now offers pre-made cable assemblies to connect remote
alarms to gas delivery systems with or without safety barriers.
Contact CONCOA for more information at 1-800-225-0473.

18
Warranty Information
This equipment is sold by CONTROLS CORPORATION OF AMERICA under the warranties set forth in the
following paragraphs. Such warranties are extended only with respect to the purchase of this equipment directly
from CONTROLS CORPORATION OF AMERICA or its Authorized Distributors as new merchandise and are
extended to the rst Buyer thereof other than for the purpose of resale.
For a period of one (1) year from the date of original delivery (90 days in corrosive service) to Buyer or to Buyer’s
order, this equipment is warrantied to be free from functional defects in materials and workmanship and to conform
to the description of this equipment contained in this manual and any accompanying labels and/or inserts, provided
that the same is properly operated under conditions of normal use and that regular periodic maintenance and service
is performed or replacements made in accordance with the instructions provided. The foregoing warranties shall
not apply if the equipment has been repaired: other than by CONTROLS CORPORATION OF AMERICA or a
designated service facility or in accordance with written instructions provided by CONTROLS CORPORATION OF
AMERICA, or altered by anyone other than CONTROLS CORPORATION OF AMERICA, or if the equipment
has been subject to abuse, misuse, negligence or accident.
CONTROLS CORPORATION OF AMERICA’s sole and exclusive obligation and Buyer’s sole and exclusive remedy
under the above warranties is limited to repairing or replacing, free of charge, at CONTROLS CORPORATION OF
AMERICA’s option, the equipment or part, which is reported to its Authorized Distributor from whom purchased,
and which if so advised, is returned with a statement of the observed deciency, and proof of purchase of equipment
or part not later than seven (7) days after the expiration date of the applicable warranty, to the nearest designated
service facility during normal business hours, transportation charges prepaid, and which upon examination, is found
not to comply with the above warranties. Return trip transportation charges for the equipment or part shall be paid
by Buyer.
CONTROLS CORPORATION OF AMERICA SHALL NOT BE OTHERWISE LIABLE FOR ANY DAMAGES
INCLUDING BUT NOT LIMITED TO: INCIDENTAL DAMAGES, CONSEQUENTIAL DAMAGES, OR
SPECIAL DAMAGES, WHETHER SUCH DAMAGES RESULT FROM NEGLIGENCE, BREACH OF
WARRANTY OR OTHERWISE.
THERE ARE NO EXPRESS OR IMPLIED WARRANTIES WHICH EXTEND BEYOND THE WARRANTIES
HEREINABOVE SET FORTH. CONTROLS CORPORATION OF AMERICA MAKES NO WARRANTY
OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE WITH RESPECT TO THE
EQUIPMENT OR PARTS THEREOF.

ADI 3199D
Certied ISO 9001
Controls Corporation of America
1501 Harpers Road Virginia Beach, VA 23454
To Order Call 1-800-225-0473 or 757-422-8330 • Fax [phone]
www.concoa.com