Rapid 7500 136, Инструкция по установке, эксплуатации и обслуживанию

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7500-S
ERIES
I
NSTALLATION
, O
PERATION AND
S
ERVICE
M
ANUAL
112 of 143
com bu stion air dampers and the mod u lating oil v al v e
in the nozzle ret u rn line thro u gh mechanical linkage.
At main flame light-off, the normally-closed oil v al v e
is energized, allo w ing oil to flo w to the nozzle. The
mod u lating oil v al v e is adj u sted to allo w a controlled
amo u nt of oil to b ypass the nozzle, w hich keeps the
press u re red u ced to the nozzle for lo w fire light off.
Nozzle oil s u pply press u re is set b y adj u sting the oil
p u mp press u re reg u lator. T u rn clock- w ise to increase
the press u re and co u nter-clock w ise to decrease the
press u re to the nozzle.
The lo w fire nozzle press u res sho u ld b e taken at the
oil p u mp ga u ge port and sho u ld b e approximately
300 PSI (20684 m b ar) w ith press u re at the nozzle
b ypass ga u ge port from 60 to 100 PSI (4136 - 6894
m b ar), these press u res v ary w ith nozzle size and jo b
conditions. A typical lo w fire oil flo w setting on the
mod u lating oil v al v e w o u ld b e n u m b er 7, bu t w ill v ary
w ith jo b conditions. After a b rief period of time for the
lo w fire flame to sta b ilize, the mod u lating act u ator w ill
dri v e the f u el/air linkage to the high fire position.
At this point, the com bu stion air dampers w ill b e f u lly-
open (or as req u ired for good com bu stion) and the
mod u lating oil v al v e w ill b e at the closed position and
the nozzle b ypass line w ill b e f u lly closed, p u tting f u ll
oil press u re to the nozzle. The oil p u mp press u re
ga u ge port press u re reading w ill sho w approximately
300 PSI (20684 m b ar) and press u res at the b ypass
press u re ga u ge port w ill b e 180 to 225 PSI (12410 -
15513 m b ar), altho u gh this w ill v ary w ith the specific
nozzle size b eing u sed. Refer to the bu rner's
man u fact u rer's man u al packed w ith the bu rner to
determine specific nozzle press u res and firing rates.
FIGURE 93: Oil Pressure Adjustments for Fully-
Modulatin
g Burner with Webster Pump
16.9 Gas Fired E q uipment Start-Up Procedures
1. Re v ie w the proced u res in this section b efore
proceeding.
2. Verify the bu rner air dampers are approxi-
mately 1/4" (.64 cm) open, and w ith the pilot
cock closed, open the main gas cock (to allo w
the lo w gas press u re s w itch, if s u pplied, to
make its circ u it).
3. Start the bu rner. With the pilot gas cock closed,
the bu rner w ill go thro u gh a b lo w er pre-p u rge
period, after w hich the pilot ignition transformer
w ill b e energized, altho u gh no pilot w ill b e
esta b lished. At the end of the pilot trial for igni-
tion and b lo w er p u rge period, the flame safe-
g u ard control sho u ld sh u t the system do w n in a
safety lock-o u t mode, req u iring man u al reset of
the flame safeg u ard control to restart the
bu rner.
4. Reset the flame safeg u ard control safety s w itch
and open the pilot gas cock. If the flame safe-
g
u ard control has a timer "Stop/R u n" s w itch,
stop the timer w hile the pilot is on and make
adj u stments as req u ired once the b lo w er pre-
p u rge period ends and the bu rner is energized.
Refer to the bu rner man u fact u rers' bu lletin for
pilot ignition adj u stments. If the flame safe-
g u ard control does not ha v e a timer "stop/r u n"
s w itch, it w ill b e necessary to keep the bu rner
in the pilot light-off position b y electrically dis-
connecting the motorized gas v al v e or mod u lat-
ing v al v e to complete pilot adj u stments.
5. With pilot adj u stments completed, reset the
timer s w itch to the "r u n" position, w hich w ill
allo w the seq u ence to proceed to the a u tomatic
gas v al v e energizing position. If the motorized
gas v al v e or mod u lating v al v e has b een dis-
connected, sh u t the bu rner off and reconnect
to allo w normal operation.
6. When the main a u tomatic gas v al v e b egins to
open, slo w ly open the firing gas cock to light off
the main flame. The main flame sho u ld light
immediately. If not, it may b e necessary to
eliminate air from the main gas line and/or
adj
u st main gas press u re reg u lator flo w rates.
7. Adj u st the bu rner as necessary to pro v ide
smooth ignition of the main flame. If the flame
signal drops significantly
w hen the main a u to-
matic gas v al v e opens, slightly increase the
pilot gas press u re to attain a sta b le flame sig-
nal v al u e.
8. For on/off bu rners - adj u st the main gas pres-
s u re reg u lator to achie v e the proper main flame
gas inp u t. Set and lock the air dampers to pro-
v ide 8.5 to 10% car b on dioxide (CO
2
) and 0%
car b on monoxide (CO). Make certain the pilot
operates relia b ly at the final f u el/air settings.
9. For high/lo w /off bu rners - adj u st the main gas
press u re reg u lator in com b ination w ith the air