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
42 of 85
10.2.1 Fire the Burner for Dun g s Combination
Gas Valves
1. Open the gas isolating v al v e.
2. Connect a s u itable press u re ga u ge to the
b u rner press u re test point.
3. Reset the locko u t b u tton of the control box and
the b u rner sho u ld no w fire. If locko u t sho u ld
occ u r w hen the main gas v al v e energises,
repeat 3 or 4 times. If after se v eral attempts the
b u rner does not fire, then t u rn the main gas
go v ernor adj u sting scre w 3 t u rns clock w ise.
See Page 41, Section 10.2 and repeat u ntil the
b u rner fires.
10.2.2 Set Gas Rate
1. S w itch on again and allo w the b u rner to fire and
to settle for a fe w min u tes.
2. Adj u st the main gas b u rner press u re to the
v al u e gi v en in the rele v ant Data Table for the
model concerned u sing the Main Gas Reg u la-
tor (accessed u nder the s w i v el co v er).
The res u lts of setting the gas flo w rate by u sing
b u rner press u re only can lead to q u ite w ide
v ariations in heat inp u t d u e to the nat u re of the
b u rners u sed.
NOTE: If the correct b u rner press u re cannot be
reached, then check the inlet press u re to the v al v e,
w ith the b u rner firing. See Technical Data Tables on
Page 11, Section 4.5 for inlet press u re
req u irements.
Do not continue to adjust the re g ulator if the
pressure is not chan g in g .
If the inlet press u re is too lo w to allo w the correct
b u rner press u re setting, then the gas inlet press u re
m u st be corrected before completing the
commissioning.
10.2.3 Check Gas Rate
It is important to check that the gas rate set d u ring
the commissioning is w ithin ± 5% of the req u ired
flo w rate.
This may be achie v ed by checking the gas flo w to
the heater w here v er possible by u sing the gas meter
and timing the flo w thro u gh the meter. The res u lts
sho u ld be compared w ith the req u ired flo w rate for
the model gi v en in the Data Tables, adj u sting the
b u rner press u re to correct for any error. Checking
the gas rate m u st be carried o u t w ith all other
appliances incl u ding any pilots, t u rned off.
1. After b u rner press u re adj u stment, allo w the
heater to operate for at least 15 min u tes and
then re-check settings.
2. Remo v e the manometer and refit all co v ers to
the v al v e and tighten the scre w of the o u tlet
press u re tap.
3. Check gas flo w rate at gas meter.
10.2.4 Control - Gas-Fired Heaters
Refer to the b u rner man u fact u rers instr u ctions for
f u rther detail. Gas b u rners ha v e t w o press u re
s w itches, one is config u red to co v er comb u stion air
and reaction to increases in comb u stion chamber
press u res. The second press u re s w itch is u sed for
monitoring the incoming gas s u pply press u re.
NOTE: The lo w gas press u re s w itch sho u ld be set at
50% of the recorded inlet w orking gas press u re.
10.2.5 Description of Gas-Fired Heater Control
The gas-fired b u rner fitted to all cabinet heaters is
controlled by a f u ll seq u ence pl u g-in control. This
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.
10.2.6 Se q uence of Operation - Sin g le 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.