CleaverBrooks FLX 1250, Руководство по эксплуатации, обслуживанию и запасным частям

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Adjustment Procedures Chapter 5
750-364 5-3
Modulation settings should be adjusted under load
conditions, until the load is maintained with the burner firing
at a steady rate. The firing rate at that point may be full high-
fire or slightly less, depending upon the relationship of the
boiler size to the load
Note: Rapid heat input can subject the
pressure vessel metal and refractory to
undesirable conditions.
B. OPERATING LIMIT
TEMPERATURE CONTROL
Set “cut-out” (burner off) temperature on the scale by
inserting a screwdriver through the cover opening to engage
the slotted head adjusting screw. The “cut-in” (burner on)
temperature is the cut-out temperature MINUS the
differential. The differential is adjusted from 5 to 30

F.
C. HIGH LIMIT TEMPERATURE
CONTROL
Set the “cut-out” (burner off) temperature on scale using the
adjusting screw. The control will break the circuit and lock
out on a rise in water temperature above the setting. The
setting should be sufficiently above the operating limit
temperature to avoid unnecessary shutdowns. The control
requires manual resetting after tripping on a temperature
increase. To reset, allow the water temperature to drop below
the cut-out setting less differential, and then press the
manual reset button.
D. LOW WATER CUTOFF DEVICES
No adjustment is required since LWCO controls are preset
by the original manufacturer. However, if the water level is
not maintained, inspect the devices immediately and
replace as required.
E. COMBUSTION AIR PROVING
SWITCH (CAPS)
Air pressure against the diaphragm actuates the switch
which, when made, completes a circuit to prove the
presence of combustion air. Since the pressure of the
combustion air is at its minimum value when the damper is
full closed, the switch should be adjusted under that
situation. It should be set slightly below the minimum
pressure, but not too close to that point to cause nuisance
shutdowns.
The run/test switch on the program relay should be set to
TEST. Turn the burner switch on. The blower will start
(provided that all limit circuits are completed) and the
programmer will remain in the low-fire (damper closed)
portion of the prepurge.
Slowly turn down the air switch adjusting screw until it
breaks the circuit. Here the programmer will lock out and
must be manually reset before it can be restarted. Add a half
turn or so to the adjusting screw to remake its circuit.