ES
FR
ENG
IT
3 CHARACTERISTICS
Fig..8
KEY
. 1. Electrode.support
. 2. Electrode.unit
. 3. Electrode.ignition.cable
. 4. Electrode.detection.cable
3.1
CONTROL BOX (fig. 8)
The. “RMG Mk.II” boilers. are. provided.
with. automatic. ignition. (without. pilot.
burner).. They. are. therefore. equipped.
electronic.control.and.protection,.with.a.
built-in. transformer,. located. inside. the.
instrument.panel.protection.box..Ignition.
and.flame.detection.is.controlled.by.two.
electrodes.located.on.the.burner..
These. guarantee. maximum. safety.
with. intervention. times,. for. accidental.
switching.off.or.gas.failure,.within.8.and.
4..seconds.(fig..8).
3.1.1 Operating cycle
Before.igniting.the.boiler,.use.a.voltme-
ter.to.make.sure.that.the.electrical.con-
nection. to. the. terminal. block. has. been.
made. properly,. respecting. the. position.
of.live.and.neutral,.as.shown.in.the.dia-
gram..Then.press.the.switch.on.the.con-
trol.panel.detecting.voltage.and.lighting.
the.led.lamp.
The.boiler.is.now.ready.to.start.working;.
a.discharge.current.is.sent.to.the.ignition.
electrode.through.the.programmer,.and.
the.gas.valve.opens.at.the.same.time..
Burner. ignition. normally. takes. place.
within.2.or.3.seconds..However,.it.is.pos-
sible. for. ignition. failures. to. occur,. with.
consequent.activation.of.signal.indicating.
that.the.equipment.has.“locked.out”..
Failures. may. be. due. to. one. of. the. fol-
lowing.causes:
–. Gas failure
. The.control.box.runs.through.the.cycle.
normally.sending.electric.power.to.the.
ignition.electrode..The.electrode.con-
tinues.spark.discharge.for.a.maximum.
of.8.and.4.sec..If.the.burner.does.not.
ignite,.the.control.box.“locks.out”.
. This. may. occur. upon. first. ignition. or.
after. long. periods. of. boiler. lay-off.
when.there.is.air.in.the.pipes..It.may.be.
caused.by.the.failure.of.the.gas.valve.
to.open.owing.to.a.break.in.the.electric.
coil..
. .
–. Ignition electrode fails to spark
. In.the.boiler,.only.opening.of.gas.to.the.
burner.is.seen.to.occur..After.8.and.4.
sec..the.control.cox.“locks.out”.
. This.may.be.due.to.there.being.a.break.
in.the.wire.of.the.electrode.or.the.wire.
not.being.properly.fastened.to.the.ter-
minal. of. the. control. box;. or. else,. the.
transformer.has.burnt.out.
.
–. No detection of flame
. The.continuous.spark.discharge.of.the.
electrode. is. noted. starting. from. igni-
tion.even.though.the.burner.is.lit..
. After. 8. and. 4. seconds. have. elapsed,.
the. sparks. cease,. the. burner. goes.
out,. and. the. warning. lamp. indicating.
equipment.“lock-out”.lights.up.
. This. occurs. when. the. position. of. live.
and.neutral.has.not.been.respected.on.
the. terminal. block.. There. is. a. break.
in. the. wire. of. the. sensing. electrode.
or. the. electrode. itself. is. earthed:. the.
electrode.is.worn.out.and.needs.repla-
cing..
. The.control.box.is.falty.
.
When. there. is. a. sudden. voltage. failure,.
the.burner.shuts.out.immediately;.when.
power. supply. returns,. the. boiler. will.
start.up.again.automatically.
3.1.2 Ionization circuit
The. ionization. circuit. is. to. be. checked.
using. a. dial-type. micro-ammeter,. or.
preferably.a.digital.micro-ammeter.with.
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