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
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v al v e, w hich, once open, allo w s gas flo w to steadily
increase from the initial light-off v ol u me u p to
req u ired firing rate.
Smooth light-off on oil is achie v ed b y the u se of a
solenoid v al v e b ypass system w hich allo w s a
red u ced amo u nt of oil to b e bu rned at light-off and
then s w itching to the req u ired firing rate once lo w fire
has b een esta b lished.
Li g ht-Off of Hi g h/Low/Off Burners
For gas, mo v a b le com bu stion air dampers are
mechanically linked w ith a slo w opening v al v e to
pro v ide a smooth light-off position. The flo w of gas is
controlled b y this v al v e w hich w ill mo v e to its
designated lo w fire v ol u me and then to its high fire
v ol u me thro u gh readj u sting the com bu stion air
dampers thro u gh mechanical linkage. As
req u irements change, the bu rner w ill mo v e b et w een
lo w fire and high fire, as needed.
For oil, the same dampers are operated b y a
hydra u lic cylinder w hich, thro u gh mechanical linkage,
pro v ides a smooth light-off in the lo w fire position and
then open to a point w here the high fire rate w ill b e
achie v ed if needed. Smooth oil light-off is f u rther
achie v ed b y the u se of a solenoid v al v e b ypass
system, w hich allo w s a red u ced amo u nt of oil to flo w
at light-off and then s w itches to the high fire rate
(sim u ltaneo u sly energizing the hydra u lic cylinder) as
needed once lo w fire has b een esta b lished.
Li g ht-Off of Fully-Modulatin g Burners
The gas system u tilizes an a u tomatic v al v e to control
the on/off flo w of the f u el. A mod u lating motor
controls the mod u lated positioning of a bu tterfly type
proportioning v al v e. The mod u lating motor also
controls the positioning of the com bu stion air
dampers, thro u gh appropriate seq u encing - pro v iding
lo w f u el/air inp u t for a smooth lo w fire start and an
infinite n u m b er of f u el air positions b et w een lo w and
high fire.
The oil system u tilizes a solenoid v al v e to control the
on/off flo w of the f u el to the oil nozzle. A mod u lating
motor controls the mod u lated positioning of a V
ported metering oil v al v e located in the oil nozzle
ret u rn line. The mod u lating motor also controls the
positioning of the com bu stion air dampers, thro u gh
appropriate seq u encing - pro v iding lo w f u el/air inp u t
for a smooth lo w fire start and an infinite n u m b er of
f u el air positions b et w een f u ll lo w and high fire.
15.2.1 Burner Control Module
T w o types of bu rner control mod u les are u sed as
standard. They are the Honey w ell RM7897 and the
RM7800. The Honey w ell model RM7897 is u sed on
air t u rno v er u nits w ith a FM compliant manifold and
less than 2,500 MBH (732.7 kW) inp u t and XL
compliant eq u ipment less than 1,000 MBH (293.1
kW) inp u t. The Honey w ell model RM7800 is u sed on
air t u rno v er u nits w ith a FM compliant manifold and
w ith 2,500 MBH (732.7 kW) inp u t and greater and on
air t u rno v er u nits w ith a XL compliant manifold and
w ith 1,000 MBH (293.1 kW) inp u t and greater. The
bu rner control mod u le is a safety de v ice and not
ser v icea b le. See Page 103, Figure 83 and Page 104,
Figure 84 for the detailed seq u ence of operation.