Improper Temperature Control - Frymaster FilterQuick FQG30 Service Manual

If popping is consistent during all hours of operation, the most likely cause is an insufficient air supply. Check for
"negative pressure" conditions in the kitchen area. If air is flowing into the kitchen area, this indicates that more air
is being exhausted than is being replenished and the burners may be starved for air.
If the fryer's gas and air supplies are correct, the problem is most likely with one of the electrical components.
Examine the ignition module and controller for signs of melting, distortion, and/or discoloration due to excessive
heat build-up in the fryer (this condition usually indicates improper flue performance). A melted or distorted ignition
module is automatically suspect and should be replaced; however, unless the condition causing excessive heat is
corrected, the problem is likely to recur.
Verify that the ignition wire is tightly connected at both ends and free of obvious signs of damage. Again, if damage
is due to excessive heat in the fryer, that problem must also be corrected. Check for proper operation by
disconnecting the wire from the ignitor (spark plug), inserting the tip of a screw driver into the terminal. With the
insulated handle of the screwdriver, hold the shaft near the frame of the fryer as the power switch is placed in the ON
position. A strong, blue spark should be generated for at least four seconds.
DANGER
Make sure you are holding the insulated handle of the screwdriver and not the blade.
The sparking charge is approximately 25,000 volts.
Examine the ignitor (spark plug) for any signs of cracking. A cracked ignitor must be replaced .
If all other causes have been ruled out, examine the burner tiles for any signs of cracking. If cracking is found, the
burner must be replaced.
Fluctuating flame intensity is normally caused by either improper or fluctuating incoming gas pressure, but may
also be the result of variations in the kitchen atmosphere. Verify incoming gas pressure in the same way as for
"popping," discussed in the preceding paragraphs. Variations in the kitchen atmosphere are usually caused by air
conditioning and/or ventilation units starting and stopping during the day. As they start and stop, the pressure in the
kitchen may change from positive or neutral to negative, or vice versa. They may also cause changes in airflow
patterns that may affect flame intensity.
Dark spots on the burner tiles are the result of an improper air/gas mixture. Adjust the combustion air blower to
reduce the amount of air in the mixture to correct this problem.
Flames shooting out of the flue are usually an indication of negative pressure in the kitchen. Air is being sucked
out of the burner enclosure and the flames are literally following the air. If negative pressure is not the cause, check
for high burner manifold gas pressure in accordance with the procedures in Section 1.7.
An excessively noisy burner, especially with flames visible above the flue opening, may indicate that the gas
pressure is too high, or it may simply be that the gas valve vent tube is blocked. If the incoming gas pressure is
correct and the vent tube is unobstructed, the gas valve regulator is probably defective.
Occasionally a burner may apparently be operating correctly, but nevertheless the fryer has a slow recovery rate (the
length of time required for the fryer to increase the oil temperature from 250ºF to 300ºF (121ºC to 149ºC)). The
primary causes of this include an over-filled frypot, a dirty or out-of-adjustment combustion air blower, low burner
manifold pressure, and/or damaged burner tiles. Adding oil to the frypot during the recovery process will also cause
a slow recovery rate.
If these causes are ruled out, the probable cause is a misadjusted gas valve regulator. Refer to Section 1.7, Checking
the Burner Manifold Gas Pressure, for the gas valve adjustment procedure.

1.10.3 Improper Temperature Control

Temperature control, including the melt cycle, is a function of several interrelated components, each of which must
operate correctly. The principle component is the temperature probe. Other components include the interface board,
the controller itself, and the ignition module.
Improper temperature control problems can be categorized into melt cycle problems and failure to control at setpoint
problems.
MELT CYCLE PROBLEMS
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