Fisher 749B Operating Manual

Instruction Manual

MCK-1179

June 2012

Types 749B and R130

Types 749B and R130 Changeover Manifolds

TYPE HSRL-749B

TYPE R130/21

Figure 1. Changeover Manifolds and Regulator Assemblies

WARNING

!

Failure to follow these instructions or
to properly install and maintain this
equipment could result in an explosion
and/or re causing property damage and
personal injury or death.

Fisher® equipment must be installed,
operated, and maintained in accordance
with federal, state, and local codes
and Emerson Process Management
Regulator Technologies, Inc.
instructions. The installation in most
states must also comply with NFPA No.
54 and 58 standards.

Only personnel trained in the proper
procedures, codes, standards, and
regulations of the LP-Gas industry
should install and service this equipment.

TYPE 64SR/122

TYPE 749B/21

Things to tell the Gas Customer:

1. Point out the regulator’s vent to the customer (or
vent assembly or vent tube), and stress that this
opening must remain unobstructed at all times.
Tell the customer to be sure to check the vent
opening after a freezing rain, sleet storm, or snow
to make sure ice has not formed in the vent.

2. Show the customer the shutoff valve on the
container. The customer should close this valve
immediately if gas is smelled, appliance pilot lights
fail to stay on or appear higher than usual, or any
other abnormal situation occurs.

3. Tell the customer to call your company to service
the regulator if the regulator vents gas or a leak
develops in the system. Only a qualied gas

service person should install or service
the regulator.

www.sherregulators.com

D450078T012

Types 749B and R130

Specications

The Specications table lists the specications for the regulators. Contact the factory if the regulators are to be used on

any sevice other than LP-Gas, natural gas, or air.

Changeover Manifold Assemblies

CAPACITY BTU/HR.

PROPANE

1,475,000

1,500,000

1. Based on 100 psig / 6.9 bar inlet, reserve setting.

(1)

(1)

TYPE

R130/21 1/4-inch FNPT 1/4-inch FNPT 45 psig 3.1 bar 30 psig 2.1 bar

749B/21 1/2-inch FNPT 1/2-inch FNPT 15 psig 1.0 bar 5 psig 0.35 bar

INLET

CONNECTIONS

OUTLET

CONNCETIONS

Commercial Automatic Changeover Regulators

CAPACITY

BTU/HR.

PROPANE

1,575,000 HSRL-749B 1/2-inch FNPT 3/4-inch FNPT 11-inches w.c. 27 mbar 9 to 13-inches w.c. 22 to 32 mbar P100A

1,210,000 64SR/122 1/2-inch FNPT 1/2-inch FNPT 10 psig 0.69 bar 5 to 20 psig 0.35 to 1.4 bar - - -

TYPE

INLET

CONNECTION

OUTLET

CONNCETION

OUTLET

PRESSURE SETTING

OUTLET PRESSURE SETTING

Supply Setting Reserve Setting

OUTLET

ADJUSTMENT RANGE

MOUNTING

BRACKET

Maximum Inlet Pressure

250 psig / 17.2 bar

Introduction

Scope of the Manual

The Instruction Manual covers installation and
maintenance for the Types 749B, R130 changeover
manifolds and the Types 64SR/122 and HSRL-749B
commercial automatic changeover regulators.

Description

Changeover Manifold Assemblies

Type R130/21—Composed of two Type 67C

regulators and a special 0 to 60 psig / 0 to 4.1 bar
pressure gauge, the Type R130/21 delivers a 45 psig /

3.1 bar outlet pressure on supply and 30 psig /

2.1 bar on reserve. The gauge, which serves as the
changeover indicator, is painted red from 0 to 35 psig /
0 to 2.4 bar. When the dial reads in the 0 to 35 psig /
0 to 2.4 bar range, it indicates that the manifold has
switched from the supply to the reserve cylinder.

Temperature Range

-20 to 160°F / -29 to 71°C

CAUTION

Capacity of all these changeover
manifolds is dependent on the size of
the second stage regulator with which
they are used.

WARNING

!

If the manifolds are used on nal-stage
(pounds-to-pounds), a relief valve is
required in the downstream system.

Commercial Automatic Changeover Regulators

Designed for large capacity multi-cylinder or tank
installations, these regulators are used on such
applications as bakeries, motels, restaurants, and
grain dryers. The manifold portion of the assembly
(Type 749B/21) consists of two Type 64 regulators and
a direct mounted Type 803 indicator.

Type 749B/21—Large capacity changeover manifold
for commercial and industrial applications. It consists of
two Type 64 regulators and a Type 803 direct indicator.

The assembly is used primarily in conjunction with
either a Type HSRL or 64SR regulator. The standard
outlet setting is 15 psig / 1.0 bar (supply) and 5 psig /

0.34 bar (reserve).

2

Type HSRL-749B—For low-pressure service. The
Type HSRL second-stage portion has the “drip lip”
vent feature and built-in travel stop to open the internal
relief valve.

Type 64SR/122—For high-pressure (pounds to
pounds) service with the second-stage composed of
Type 64SR that has internal relief.

1ST STATE CHANGEOVER
MANIFOLD SECTION

Types 749B and R130

PRESSURE GAUGE OR
INDICATOR WITH RED
WARNING FLAG

C

O

N

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S

L

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S

A

A

F

M

SUPPLY INLET

SUPPLY

VENT

POINT ALL VENTS DOWN

T40469

FINAL STAGE REGULATOR

Figure 2. Changeover Regulator

Operation

The Changeover Manifold (Figure 2) consists of two

regulators (supply and reserve) and an indicator
that denotes when the reserve regulator is in
operation. The “Supply” regulator has the handwheel
labelled “SUPPLY”.

Open both container valves slowly. Gas will now ow

from both containers through the piping into the

rst-stage section of the regulator manifold by way of
the inlet ttings. When the reserve pressure setting
(see Specications) is reached in the rst-stage

regulator manifold, the disk assembly in the reserve
regulator will shutoff gas from the “Reserve” container.

Gas from the “Supply” container will continue to enter
the supply regulator until the supply pressure setting

(see Specications) is maintained. Any second or
nal stage regulator reduces this pressure for use by

the appliance.

The “Supply’’ side of the regulator manifold will

continue to supply gas as long as sufcient gas

remains in the “Supply” container. When pressure
in the “Supply” side container drops to the reserve
setting, the “Reserve” side of the regulator manifold

C

O

N

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T

E

R

O

H

S

L

I

I

N

E

U

D

S

S

A

A

F

M

s

VENT

O

N

C

T

R

R

E

O

H

L

S

I

S

N

I

E

U

D

S

A

F

A

M

VENT

RESERVE INLET

FINAL STAGE
REGULATOR

will open and maintain the reserve setting to the
second-stage regulator, which continues to regulate
the pressure to the appliance. At the time the
pressure in the “Supply” container drops to the

reserve side pressure, a red warning ag appears in

the indicator window or the pressure gauge pointer
drops into the red section (Type R130) and also on
the remote indicator if one is used.

Switching Supply Containers

WARNING

!

The open line (pigtail or hose) must be
capped because gas will escape to the
atmosphere through the open
connection if pressure in the supply
cylinder drops to the reserve pressure
setting (red indicator ag visible).

Refer to Figure 3. Once the “Supply” container is
empty, remove the “Reserve” cap (key 4) which is
attached to the chain assembly (key 8) and the “Supply”
handwheel (key 3) by turning them counter-clockwise.
Do not remove the adjusting screw (key 5) or the nut
(key 1) on the adjusting screw. Screw the “Supply”

3