Fisher® regulators must be installed,
operated, and maintained in accordance
with federal, state, and local codes, rules
and regulations, and Emerson Process
Management Regulator Technologies,
Inc., instructions.
For LP-Gas service, an approved
regulator (such as one listed by U.L.)
should be used. The installation,
in most states, must comply with
NFPA standards.
If the regulator vents gas or a leak
develops in the system, service to
the unit may be required. Failure
to correct trouble could result in a
hazardous condition.
Call a gas service person to service
the unit. Only a qualied person must
install or service the regulator.
Introduction
Scope of the Manual
This instruction manual provides instructions for
installation, adjustment, maintenance, and parts
ordering information for Types S201, S201H, S201K,
S202, and S202H gas service regulators.
Description
S201 and S202 Series regulators are typically
installed on industrial and commercial applications.
The Types S202 and S202H regulators contain an
internal relief valve. Units with an “H” or “K” sufx
are similar to the basic regulators but deliver a higher
outlet pressure of 1 to 5 psig (69 mbar to 0,35 bar) and
2 to 10 psig (0,14 to 0,69 bar), respectively.
Specications
The Specications section lists the specications for
the regulators. The following information is stamped
on the regulator at the factory: type number, date of
manufacture, spring range, orice size, maximum inlet
pressure, maximum operating outlet pressure, and
outlet pressure which may damage regulator parts.
www.emersonprocess.com/regulators
D400007X012
S201 and S202 Series
TypeS202
Specications
Available Congurations
See Figure 3
Body Size and End Connection Styles
1-1/2 or 2 NPT inlet and outlet and
NPS 2 (DN 50) CL125 FF anged
Maximum Allowable Inlet Pressures
(1)
See Table 1
Maximum Emergency Outlet Pressure
15 psig (1,0 bar)
Outlet Pressure Range
(1)
Orice Size
1/4, 3/8, 1/2, 3/4, 1, and 1-3/16-inches
(6,4; 9,5; 13; 19; 25; and 30 mm)
Temperature Capabilities
-20° to 150°F (-29° to 66°C)
Pressure Registration
Internal
Approximate Weight
22 pounds (10 kg)
2.0-inches w.c. to 10 psig (5 mbar to 0,69 bar)
1. The pressure/temperature limits in this Instruction Manual and any applicable standard or code limitation for valve should not be exceeded.
CONTROL
SPRING
VALVE DISK
DIAPHRAGM
RELIEF VALVE
SPRING
VALVE DISK
DIAPHRAGM
PUSHER POST
A6197A6198
INLET PRESSURE
OUTLET PRESSURE
ATMOSPHERIC PRESSURE
ORIFICE
TYPE S201TYPE S202
Figure 2. Operational Schematics
Principle of Operation
Refer to Figure 2. When downstream demand
decreases, the pressure under the diaphragm
increases. This pressure overcomes the regulator
setting (which is set by the control spring). Through
the action of the pusher post assembly, lever, and
valve stem, the valve disk moves closer to the orice
and reduces gas ow. If demand downstream
increases, pressure under the diaphragm decreases.
Spring force pushes the pusher post assembly
downward, and the valve disk moves away from the
orice, and the gas ow increases.
The Types S202 and S202H regulators include an
internal relief valve. Internal relief is used to help
minimize overpressure. Any outlet pressure above
the start-to-discharge point of the non-adjustable relief
spring moves the diaphragm off of the relief seat,
allowing excess pressure to discharge through the vent.
Typical start-to-discharge values are 7-inches w.c. to
2 psi (17 to 138 mbar) above the outlet pressure
setting, depending on control spring used.
PUSHER POST
ORIFICE
2
S201 and S202 Series
TYPE NUMBER
S20
REGULATOR TYPE
1Regulator, 2 to 30-inches w.c. (5 to 75 mbar) outlet range
2Regulator, 2 to 30-inches w.c. (5 to 75 mbar) outlet range with Internal Relief
PRESSURE OUTLET RANGE
HHigh-Pressure Regulator, 1 to 5 psi (0,07 to 0,34 bar) outlet range with heavy diaphragm plate
KHigh-Pressure Regulator with external adjusting screw, 2 to 10 psi (0,14 to 0,69 bar) outlet range (Not an option for S202)
Installation
WARNING
!
Personal injury or system damage
may result if this regulator is installed,
without appropriate overpressure
protection, where service conditions
could exceed the limits given on the
Specications section and regulator
nameplate. Regulator installations
should be adequately protected from
physical damage.
All vents should be kept open to permit
free ow of gas to the atmosphere.
Protect openings against entrance of
rain, snow, insects, or any other foreign
material that may plug the vent or vent
line. On outdoor installations, point the
spring case vent downward to allow
condensate to drain (see Figure 4). This
minimizes the possibility of freezing and
of water or other foreign materials from
entering the vent and interfering with
proper operation.
Under enclosed conditions or indoors,
escaping gas may accumulate and be
an explosion hazard. In these cases,
the vent should be piped away from the
regulator to the outdoors.
OPTIONS
Figure 3. Available Congurations
AJ4698
A1121
Figure 4. Type S201 Regulator Installed with the Vent
Pointed Downward and with a Type 289H Relief Valve for
any portion of the regulators beyond the
limits in the Specications section and
Table 1 may cause leakage, damage to
regulator parts, or personal injury due to
bursting of pressure-containing parts.
Some type of external overpressure
protection should be provided if inlet
pressure will be high enough to damage
downstream equipment. Common
methods of external overpressure
protection include relief valves,
monitoring regulators, shutoff devices,
and series regulation.
TYPE S201
REGULATOR
PROTECT VENT PIPE
WITH RAIN CAP
High Capacity Relief
NPS 2 (DN 50)
TYPE 289H
RELIEF VALVE
CAUTION
S201 and S202 Series regulators have
an outlet pressure rating lower than
their inlet pressure rating. If actual inlet
pressure can exceed the outlet pressure
rating, outlet overpressure protection
is necessary. However, overpressuring
If the regulator is exposed to an
overpressure condition, it should be
inspected for any damage that may
have occurred. Regulator operation
below these limits specied in the
Specications section and Table 1 does
not preclude the possibility of damage
from external sources or from debris in
the pipeline.
3
S201 and S202 Series
Table 1. Maximum Allowable Inlet PressuresTable 2. Maximum Outlet Pressure Setting
for dirt or foreign matter which may have accumulated
in the regulator body or in the pipeline. Apply pipe
compound to the external threads of the pipeline and
install the regulator so that ow is in the direction of
the arrow cast on the body. The diaphragm casing
assembly can be rotated to any position relative to the
body. Loosen the two cap screws (key 18, Figure 5) in
order to rotate the diaphragm casing assembly.
Do not install the regulator in a location where there
can be excessive water accumulation, such as directly
beneath a downspout.
If the regulator is used in conjunction with a Type 289H
relief valve, it should be installed as shown in Figure 4.
The outside end of the vent line should be protected
with a rainproof assembly.
The Type 289H should be set 10-inches w.c. (25 mbar)
higher than the outlet pressure setting of the regulator,
up to 30-inches w.c. (75 mbar) outlet pressure. For
pressure greater than this, set the Type 289H 0.75 psi
(0,05 bar) higher than the outlet pressure setting of
the regulator.
The S201 and S202 Series regulators have 1 NPT
screened vent openings in the spring case. If
necessary to vent escaping gas away from the
regulator, install a remote vent line in the spring
case tapping. Vent piping should be as short and
direct as possible with a minimum number of bends
and elbows. The remote vent line should have the
largest practical diameter. Vent piping on regulators
with internal relief (Types S202 and S202H) must
be large enough to vent all relief valve discharge to
atmosphere without excessive backpressure and
resulting excessive pressure in the regulator.
Periodically check all vent openings to be sure that
they are not plugged.
Maximum outlet pressure settings are shown in
Table 2. Outlet pressure more than 2 psi (0,14 bar)
(light diaphragm head) or 3 psi (0,21 bar) (heavy
diaphragm head) above the setpoint may damage
internal parts such as the diaphragm head and valve
disk. The maximum emergency (casing) outlet
pressure is 15 psig (1,0 bar).
Startup
CAUTION
Pressure gauges should always be used
to monitor downstream pressure during
startup. Procedures used in putting this
regulator into operation must be planned
accordingly if the downstream system is
pressurized by another regulator or by a
manual bypass.
If the downstream system is not pressurized by
another regulator or manual bypass valve, use the
following procedure to startup the regulator.
4
S201 and S202 Series
1. Check to see that all appliances are turned off.
2. Slowly open the upstream block valve.
3. Check inlet and outlet pressure for correct values.
4. Check all connections for leaks.
5. Light the appliance pilots.
Adjustment
The range of allowable pressure settings is stamped
on the nameplate. If the required setting is not within
this range, substitute the correct spring (as shown
in Table 3). If the spring is changed, change the
nameplate to indicate the new pressure range.
A pressure gauge should always be used to monitor
downstream pressure while adjustments are being made.
1. Remove the closing cap (key 4, Figure 5) or
loosen the hex locknut.
2. To increase the outlet setting, turn the adjusting
screw (key 3, Figure 5) clockwise. To decrease
the outlet setting, turn the adjusting
screw counterclockwise.
3. Replace the closing cap or tighten the hex locknut.
Regulators that have been disassembled
for repair must be tested for proper
operation before returned to service.
Only parts manufactured by Emerson
Process Management Regulator
Technologies, Inc. should be used for
repairing Fisher® regulators. Relight
pilot lights according to normal
startup procedures.
Due to normal wear or damage that
may occur from external sources, this
regulator should be inspected and
maintained periodically. The frequency
of inspection and replacement of parts
depends upon the severity of service
conditions or the requirement of local,
state, and federal rules and regulations.
Disassembly to Replace Diaphragm
1. Remove the closing cap (key 4, Figure 5) or
loosen hex locknut. Turn the adjusting screw
or nut (key 3) counterclockwise to ease
spring compression.
2. For Types S201, S201H, S202, and S202H units,
remove the adjusting screw and spring (key 2).
Shutdown
Installation arrangements may vary, but in any
installation it is important that the valves be opened
or closed slowly and that the outlet pressure be
vented before venting inlet pressure to prevent
damage caused by reverse pressurization of the
regulator. The steps below apply to the typical
installation as indicated.
1. Open the vent valves downstream of the regulator.
2. Slowly close the upstream block valve.
3. Inlet pressure will automatically be released
downstream as the regulator opens in response
to the lowered pressure on the diaphragm.
Maintenance
WARNING
!
To avoid personal injury or equipment
damage, do not attempt any
maintenance or disassembly without
rst isolating the regulator from system
pressure and relieving all internal
pressure as described in “Shutdown”.
For Type S201K remove the adjusting screw,
hex locknut, and closing cap (key 4), the upper
spring seat (key 6), and spring (key 2).
3. Remove hex nuts (key 15) and cap screws
(key 14). Separate the upper spring case (key 1)
from the lower casing assembly (key 9).
Note
If disassembling a Type S202 or S202H
regulator, lift the upper spring case
straight up in order to avoid hitting the
stem (key 24).
4. Slide the diaphragm and diaphragm head assembly
(key 7) away from the body (key 21) to unhook the
pusher post (key 8) from the lever (key 10). Lift off
the diaphragm and diaphragm head assembly.
5. Unscrew the cap or reset stem (key 24) which
fastens the lower spring seat (key 6) to the
pusher post to separate the lower spring seat,
diaphragm and diaphragm head assembly, and
pusher post. (The relief valve spring (key 25) will
also have to be removed from Types S202 and
S202H regulators).
5
S201 and S202 Series
Note
Take care not to pinch or tear the
diaphragm when reassembling.
6. Reassemble the spring case unit in the reverse
order of the above steps. Before tightening the
cap screw or stem into the pusher post, place
the loosely-assembled diaphragm and diaphragm
head assembly into position in the lower casing,
being sure that the pusher post is hooked on
the lever. Rotate the diaphragm so that the
diaphragm and lower casing holes are aligned.
Tighten the screw or stem.
CAUTION
Before tightening cap screws (key 14),
replace the spring and adjusting screw.
Turn the adjusting screw to about
mid position. This will stretch the
oversized diaphragm to ensure slack in
the assembled diaphragm. The slack
created by this method is necessary
for good regulation. Be sure the
diaphragm does not fold over at the
ange when reassembling.
Disassembly to Replace Valve Disk,
Orice, and O-Rings
1. Remove the cap screws (key 18, Figure 5) which
hold the lower spring casing (key 9) to the body
(key 21). Separate the lower spring casing from
the body.
2. Check the body O-ring (key 19) for wear.
3. Examine the valve disk (key 16) for nicks, cuts,
and other damage. Unscrew the disk holder
assembly (key 16) and replace it with a new part
if necessary.
4. If the seating edge of the orice (key 20)
is nicked or rough, remove the orice from
the body. Change to a new part when
reassembling the regulator. (If the orice is
replaced with a different size, change
the nameplate to state the new size and
maximum inlet pressure).
5. Reassemble the regulator in reverse order of the
above steps.
Parts Ordering
The type number, orice size, spring range, and
date of manufacture are stamped on the nameplate.
Always provide this information in any correspondence
with your local Sales Ofce regarding replacement
parts or technical assistance.
When ordering replacement parts, reference the key
number of each needed part as found in the following
parts list. Separate kit containing all recommended
spare parts is available.
Parts List
Key Description Part Number
Spare Parts (Repair Parts Kit includes
keys 5, 7, 16, and 19)
Types S201, S202 RS201X00012
Types S201H, S202H RS201HX0012
Type S201K RS201KX0012
1 Spring Case
Aluminum 4L142308032
Pinned for heavy spring 1J718699022
Brass, Type S201K (2 required) 1H797414012
7* Diaphragm and Diaphragm Head
Types S201, S202 - Use with
1D8933 and lighter springs 1L1544X0012
Types S201H and S202H - Use
with 1H9758 and heavier springs 1L1545X0012
Type S201K (Diaphragm only) 1K649602052
Emerson Process Management
Regulator Technologies, Inc.
USA - Headquarters
McKinney, Texas 75069-1872 USA
Tel: 1-800-558-5853
Outside U.S. 1-972-548-3574
Asia-Pacic
Shanghai, China 201206
Tel: +86 21 2892 9000
Europe
Bologna, Italy 40013
Tel: +39 051 4190611
Middle East and Africa
Dubai, United Arab Emirates
Tel: +971 4811 8100
For further information visit www.emersonprocess.com/regulators
The Emerson logo is a trademark and service mark of Emerson Electric Co. All other marks are the property of their prospective owners. Fisher is a mark owned by Fisher Controls, Inc., a
business of Emerson Process Management.
The contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their accuracy, they are not to be construed as warranties or
guarantees, express or implied, regarding the products or services described herein or their use or applicability. We reserve the right to modify or improve the designs or specications of such
products at any time without notice.
Emerson Process Management does not assume responsibility for the selection, use or maintenance of any product. Responsibility for proper selection, use and maintenance of any Emerson
Process Management product remains solely with the purchaser.
Natural Gas Technologies
Emerson Process Management
Regulator Technologies, Inc.
USA - Headquarters
McKinney, Texas 75069-1872 USA
Tel: 1-800-558-5853
Outside U.S. 1-972-548-3574
Asia-Pacic
Singapore, Singapore 128461
Tel: +65 6777 8211
Europe
Bologna, Italy 40013
Tel: +39 051 4190611
Gallardon, France 28320
Tel: +33 (0)2 37 33 47 00
TESCOM
Emerson Process Management
Tescom Corporation
USA - Headquarters
Elk River, Minnesota 55330-2445 USA
Tel: 1-763-241-3238
Europe
Selmsdorf, Germany 23923
Tel: +49 (0) 38823 31 0