L404F,T,V PRESSURETROL
®
CONTROLLERS
5
71-2429—06
Fig. 3. Typical locations of pressure controllers in an oil burner system.
Fig. 4. Mounting an oil pressure controller
directly on the main pipe.
Using with Preheated Oil
When used with preheated oil, a siphon loop must always be
connected between the controller and the main pipe (see Fig.
5) to provide thermal buffering.
Fig. 5. Mounting of a siphon loop, with approximate
dimensions in in. (mm).
WIRING
WARNING
Electrical Shock Hazard.
Can cause severe injury, death or property damage.
Disconnect the power supply before beginning wiring.
More than one power supply disconnect may be
required.
All wiring must comply with applicable codes and ordinances.
All models have terminals (on the MicroSwitch
®
snap-acting
switch) inside the cover and knockouts for conduit and cable.
Refer to manufacturer installation and wiring instructions, if
available, and to typical hookups shown in Fig. 6 to 10.
Fig. 6. L404F in low voltage relay circuit.
MAIN
OIL
LINE
TO OIL
BURNER
ATOMIZER
ATOMIZING MEDIUM
(AIR OR STEAM)
MANUAL
SHUTOFF
VALVE
LOW OIL
PRESSURE
CONTROLLER
HIGH OIL
PRESSURE
CONTROLLER
RECIRCULATING
VALVE AND SAFETY
SHUTOFF VALVE
OIL
PUMP WITH
PRESSURE RELIEF
LOW OIL
TEMPERATURE
STRAINER
MANUAL
SHUTOFF
VALVE
M17861
OIL PRESSURE
CONTROLLER
(AT RIGHT
ANGLES TO THE
MAIN PIPE LINE)
PIPE
WRENCH
HEXAGONAL
FITTING
MAIN PIPE LINE
M17860
MAIN TEE
(TURN TO LEVEL
THE CONTROLLER)
PIPE NIPPLE
4-1/2
TO
5-1/2
(114 TO
140)
PREHEATED OIL SUPPLY LINE
SIPHON LOOP
TEE
OIL PRESSURE
CONTROLLER
M23886
1
1 1/4 INCH PIPE WITH 1/4-18 NPT EXTERNAL THREADS ON
BOTH ENDS AND 2-1/4 IN. (57 MM) DIAMETER LOOP.
M19637A
1
1
2
2
PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION
AS REQUIRED.
AS SHOWN, SWITCH OPENS ON PRESSURE RISE. REVERSE
ACTING (MAKE ON PRESSURE RISE) UNITS ARE WIRED TO
R-W TERMINALS AND TERMINAL B IS OMITTED.
L404F PRESSURETROL
24 VOLT
POWER
SUPPLY
R
W
B
L1
(HOT)
POWER
SUPPLY
24 VOLT RELAY
L2