Roberts Gorden Combat MGB0100, Руководство по установке

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COMBAT
®
C
ABINET
H
EATERS
I
NSTALLATION
, C
OMMISSIONING
, O
PERATION AND
S
ERVICE
M
ANUAL
44 of 85
control ens u res the safe start and stop seq u ence
and also monitors the safe presence of a flame and
b
u rner air press u re.
10.3.5 Se q uence of Operation - Two-Sta g e
Burner
1. With the external controls on calling for heat,
and the press u re s w itch at rest, the b u rner fan
w ill s w itch on after the control does a "self
check".
NOTE: If the press u re s w itch contacts (normally
closed) are open, the heater w ill not start.
2. The comb u stion air fan t u rns on and the pres-
s u re s w itch contacts close w ithin the next 5
seconds to indicate s u fficient comb u stion air or
locko u t w ill occ u r.
3. The seq u ence contin u es w ith a p u rge period
w ith the b u rner fan r u nning.
4. The electrical ignition s w itches ON at the end of
the p u rge period.
5. The main gas v al v e opens and once a flame
has been established, this remains open u ntil
close do w n. The flame probe is no w contin u -
o u sly monitoring for the safe presence of flame.
6. Three seconds later, the electric ignition t u rns
off, lea v ing the gas flame to be pro v ed as sta-
ble.
7. The control is no w in its normal r u n position.
8. If the fl u e becomes blocked d u ring the u nits
operation, the u nit w ill deacti v ate and the lock-
o u t indicator light w ill acti v ate.
After setting the minim u m b u rner inp u t and
comb u stion, the follo w ing check m u st be made:
R u n the heater on lo w fire for a minim u m of 15
min u tes. Check the fl u e gas temperat u re. If the fl u e
gas temperat u re falls belo w 125° C, increase the lo w
fire gas setting u ntil the temperat u re reaches 125° C,
other w ise condensation may form.
10.4 Motor Starter and Thermal Overload
On belt-dri v en models, the motor is controlled by a
direct on-line contactor starter fitted w ith thermal
o v erload protection. If the thermal o v erload
operates, the main fan w ill not r u n. To reset, press
the reset b u tton on the o v erload u nit.
NOTE: For models w ith a 5.5 kW motor or larger, the
direct on-line starter w ill be replaced by an
a u tomatic starter.
The o v erload sho u ld be set to indicate
approximately 0.2 A abo v e the normal r u nning
c u rrent of the heater. See Page 11, Section 4.4 .
10.4.1 Burners
For details of the packaged b u rners, see the
man u fact u rer's instr u ctions and Page 11, Section
4.5 through Page 14, Section 4.8 . When reading the
data tables, ens u re that the correct table for the
b u rner and gas v al v e installed is being u sed. The
data tables are listed u nder a b u rner reference letter
w hich can be fo u nd on the heater data plate.
10.5 Gas Valves
Dun g s Combination Gas Valve
All model 015 - 030 gas-fired b u rners operate as
direct main flame ignition and ha v e no separate start
gas train. All other models operate w ith a first stage
start gas flame s u pplied from a start gas train
containing a start gas press u re reg u lator and t w o
safety sh u t-off v al v es, for all gas types.
The main gas is released at the second stage, and
the combination main gas
v al v e block contains a
main b u rner press u re reg u lator and t w o safety
sh u toff v al v es, for all gas types. See Page 44, Figure
19 . Please refer to the man u fact u rer's instr u ctions
for setting the controls.
Fi g ure 19: Gas Train Circuit for Dun g s Gas Valves (all models)