®
L404F,T,V PRESSURETROL CONTROLLERS
Pressure Gauge Mounting
INSTALLATION
To mount beside a pressure gauge, remove the gauge, and
install in its place the steam trap with a tee on top. Mount the
®
When Installing This Product…
PressureTrol unit and pressure gauge on the side of the tee
1. Read these instructions carefully. Failure to follow them
could damage the product or cause a hazardous
condition.
by means of nipples and elbows (see Fig. 2).
Remote Mounting
Excessive vibration at the boiler may affect the operation of the
L404F. In these cases, the L404F should be remotely located,
subject to the following:
2. Check on the ratings given in the instructions and
marked on the product to make sure the product is
suitable for your application.
3. Installer must be a trained, experienced service
technician.
1. All piping must be suitable and properly pitched to drain
all condensation back to the boiler.
2. The remote mounting must be solid.
4. After installation is complete, check out the product
operation as provided in these instructions.
3. A steam trap must be used at one end of the piping.
IMPORTANT
When making pipe connections, use pipe dope
sparingly to seal the joints; any excess dope may clog
the small hole in the fitting and prevent the controller
from operating properly.
Boiler Mounting
If it is not convenient to mount the L404F adjacent to the
pressure gauge, install a steam trap at the location
recommended by the boiler manufacturer, then screw the
device directly to the steam trap.
Location and Mounting (L404F)
Locate the L404F where the ambient temperature will not
exceed 66°C (150°F). The L404F can be mounted near the
pressure gauge, at a remote location, in a fitting provided by
the boiler manufacturer, or in a special mounting on low water
cutoffs. The L404F should always be mounted above the water
line in steam boiler applications.
Location and Mounting (L404T,V)
Location
NOTE: For most accurate operation, supplemental heat
should be added to installations where the
NOTE: For accurate operation, supplemental heat should be
added to installations where temperatures fall below
-29°C (-20°F).
temperature falls below -20°F (-29°C).These
controllers can be mounted at any location in the oil
supply line, depending on the application. Typical
locations are shown in Fig. 3. The low oil pressure
controller should be located upstream from the safety
shutoff valve(s). In a downstream location, there
would be zero pressure when the burner is not
running and the safety shutoff valve(s) is (are) closed.
This could prevent startup or require manual reset
every time the burner is started. The high oil pressure
controller should be located as near to the burner as
possible.
A steam trap must be connected between the L404F and the
boiler (see Fig. 2) to prevent boiler scale and corrosive vapors
from attacking the elbows or diaphragm.
PRESSURE
GAUGE
PRESSURE
CONTROLLER
Mounting
TEE
Mount the oil pressure controller directly on the main pipe.
Insert a tee in the pipe line, and connect a pipe nipple of
appropriate size to the tee (see Fig. 4). Screw the hexagonal
fitting (1/4-18 NPT internal thread) of the pressure controller to
the pipe nipple. To avoid leaks and damage to the case, use a
parallel jaw wrench on the hexagonal fitting close to the pipe
nipple. Do not tighten the pressure controller by hand by
holding the case.
STEAM TRAP
(SIPHON LOOP)
1
4-1/2 TO 5-1/2
(114.3 TO 139.7)
Make all pipe connections in accordance with approved
standards. Use only a small amount of pipe compound to seal
the connection joints. Excess pipe compound may clog the
orifice in the pipe fitting and prevent the controller from
operating properly.
BOILER
1
1/4 IN. PIPE WITH 1/4 - 18 NPT EXTERNAL THREADS
ON BOTH ENDS AND 2-1/4 IN. DIAMETER LOOP.
M23885
Fig. 2. Steam trap mounting.
71-2429—06
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