Operation - Fisher R130/21 Instruction Manual

SUPPLY INLET

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 flow
from both containers through the piping into the
first-stage section of the regulator manifold by way of
the inlet fittings. When the reserve pressure setting
(see Specifications) is reached in the first-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 Specifications) is maintained. Any second or
final 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 sufficient 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
ST
1 STATE CHANGEOVER
MANIFOLD SECTION
SUPPLY
VENT
POINT ALL VENTS DOWN
T40469
Figure 2. Changeover Regulator
Types 749B and R130
PRESSURE GAUGE OR
INDICATOR WITH RED
WARNING FLAG
VENT
VENT
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 flag 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
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 flag 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"
RESERVE INLET
FINAL STAGE
REGULATOR
WARNING
!
3