Wayne HSG200 Manual - page 20
PAGE 19
TECHNICAL INFORMATION
“Troubleshooting Guide”
NUISANCE LOCKOUTS/FLAME SENSING PROBLEMS - HSG200 & HSG400 GAS BURNERS
Wayne’s HSG series direct spark ignition (DSI) gas
burners prove flame through the process of flame
rectification. Flame rectification is achieved by placing a
small voltage on the flame sensing probe. When the
probe is surrounded by flame, the voltage on the probe
“leaks” to ground through the flame, resulting in an
electrical current. This current is interpreted by the
ignition control as the presence of flame.
One of the most common problems with gas appliances
utilizing this type of electronic flame sensing system is
the “nuisance lockout”. Lockouts are not generally due
to the burner failing to ignite, but rather simply the failure
of the system to sense the establishment of flame.
Should this situation exist for a period of time longer
than the ignition control’s state lockout timing, the
control will shut down or go into permanent lockout. The
only way to get the burner to recycle is to break, and
then reinstate power to the burner.
The following situations can lead to flame sensing
problems and can be checked without
disassembling the burner:
•
The burner is not properly grounded to “earth
ground” on the line voltage.
•
The ignition control is not properly grounded to the
burner itself. Using an ohmmeter, check the wire
attached to both parts for good contact and
continuity.
•
The burner ignition control is polarity sensitive. The
polarity of the incoming line voltage may be
reversed. Verify that black and white wires are hot
and neutral respectively, and that they are
connected to the corresponding black and white
wires on the burner.
The remaining checks and/or adjustments require
removal of the gas train:
•
The connections from the “SENSE” terminal of the
ignition control to the end of the flamerod may be
broken at some point. Check all quick connect
terminations and connections. Check the continuity
with an ohmmeter while flexing wires to assure no
hidden conductor breakage exists. If replaced,
wiring must be of equal, or heavier gauge and
equal, or better temperature rating.
•
The flamerod probe may be grounded out. Assure
that the flamerod probe is not touching the burner
head. The probe should be positioned in the center
of the clearance groove on the outer edge of the
burner head with approximately 1/16” (1.5875mm)
clearance from the head. The probe must not be
positioned to far away from the head as this may
result in grounding out of the probe against the
inside surface of the air tube.
• The flamerod probe should be free of soot and
creosote. Deposits may insulate the probe, leading
it not to pass the electrical charge to the flame. The
probe can be cleaned with steel wool, emery paper
or fine sandpaper. NOTE: This is the leading cause
of nuisance lockouts in dual-fuel wood/gas fired
appliances.
•
The flamerod probe may be burned away. Check it
against dimensions on the ELECTRODE AND
FLAMEROD PROBE SETTINGS drawing.
•
The dimensional location of the flamerod probe may
be incorrect, or the probe may be bent out of shape.
Check it against dimensions on the ELECTRODE
AND FLAMEROD PROBE SETTINGS drawing and
adjust if necessary.
•
The spark electrode gap may be incorrect, resulting
in no spark or an inadequate spark that will not
ignite the gas properly. Check the electrode gap
against the ELECTRODE AND FLAMEROD
PROBE SETTINGS drawing and adjust if required.
•
The high tension lead conductor from the ignition
transformer to the tip of the spark electrode may be
broken, preventing the high voltage current from
getting to the electrode tip. Check all connections
thoroughly and/or check to continuity of the lead
wire assembly with an ohmmeter.
Once all of the items listed previously have been
carefully checked and corrected if necessary, reinsert
the gas train assembly into the burner. NOTE: Be
careful not to bend the air proving switch sail arm (if so
equipped) or accidentally reposition either the flamerod
probe or electrode during reinstallation of the gas train
assembly.
If, after all of the above listed items have been carefully
checked, the burner still fails to work, it is due to one or
more of the following problems:
1. Unit sparks and fires but will not stay lit. Ignition
control module is malfunctioning and must be
replaced.
2. Unit does not spark. Ignition transformer is bad and
must be replaced.