Blue Seal 203926, Руководство по обслуживанию

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Revision 7/F3527
© Moffat Ltd, November 2004
small hole on the front face of the ignition box
at the top.
Inspect for Diagnostic Indicator as follows:
Fenwal Ignition Box
- 2 Flashes Indicates that there was a flame
already present when ignition
attempted.
Possible gas valve fault (burner
staying on). Refer to fault
diagnosis - Gas Valve Faulty.
- 3 Flashes Indicates LOCK-OUT condition.
Possible flame rectification rod
short to earth. Refer to fault
diagnosis 6.1.2 - Burner Flame
Not Being Sensed.
White Rodgers Ignition Box
- Steady ON Indicates internal or external
electrical fault.
Check all wiring.
- Flashing Indicates LOCKOUT condition.
Possible flame rectification rod
short to earth. Refer to fault
diagnosis 6.1.2 - Burner Flame
Not Being Sensed.
If ignition box fault indicator LED does not
identify fault, and voltage correct but no spark
generated, ignition box is faulty - replace.
NOTE: Ensure all wiring and connections to
ignition box are correct before replacing.
Ensure unit has Earth/Ground connection
on unit and at supply.
If ignition box generates a spark, but burner
doesn’t ignite, or if burner ignites but doesn’t
stay alight, firstly check correct electrode
assembly operation. Refer fault diagnosis
6.1.2 - Burner Ignition Spark Not Working.
If all checks are correct, but burner fails to
stay alight then burner box is faulty - replace.
NOTE: Correct flame sensing current can be
checked by inserting a multi-meter capable of
measuring micro-amps in series with flame
rectification rod connection to ignition box.
With power off, disconnect flame rectification
rod connection to ignition box (terminal ‘S1’ on
Fenwal models, terminal ‘FP’ on White
Rodgers models), and connect multimeter
between flame rectification rod lead and
ignition box terminal. Turn on power and
Ignition box faulty - 220-240 Volt models
only
The direct spark ignition control boxes used
on 220-240 volt model G32’s are operated
from direct voltage supply from the
thermostat / hold thermostat circuit.
Correct ignition box operation should result in
ignition box commencing spark at ignition
electrodes and opening gas valve to ignite
burner, then maintain burner on after
successful ignition.
IMPORTANT: Certain models have a
pre-purge period before the spark and gas
valve opening commences. Refer appendix
B.2 for pre-purge specifications according to
ignition box type.
Where a pre-purge is applicable this will result
in a 5 second delay on spark and gas valve
opening from when thermostat or hold
thermostat calls for heat.
NOTE: On UK market models prior to serial
number 203927, the thermostat heating
indicator light remains off during pre-purge.
If no spark generated or heard, check that
ignition box has correct supply voltage (when
thermostat in ON).
For UK market models prior to serial number
203927 using Teknigas ignition box, check
correct supply voltage across ignition box
terminals 1 (black neutral wire at bottom), and
terminal 8 (red phase wire, 3rd from top), on
connector block at front of ignition box.
For non-UK market models prior to serial
number 203927, using Scarico / Ispracontrols
ignition box, check correct supply voltage on
ignition box wires connecting to terminal 1 of
hold thermostat, and a control panel neutral
wire. This confirms that the thermostat circuit
is supplying the correct voltage to the ignition
box connection wires. To confirm actual
voltage to ignition box, the 6-way connector
on the ignition box requires removal to check
actual voltage in ends of 6 way connector for
these two wires.
For all 220-240 volt models after serial
thermostat. With burner running a current of
no less than that specified below should be
read.
Fenwal Models
0.7 micro Amps
White Rodgers Models 1.0 micro Amps
If no current reading, or less than specified,
re-check electrode settings, gas pressure, gas
type etc, and if still not correct, ignition box
requires replacement.