Improper Temperature Control; Problems Related To Gas/Electrical Power Supplies; Problems Related To Electronic Circuits - Frymaster BIH52 Series Service Manual

3. Improper temperature control

4. Computer-related problems
5. Filtration problems
6. Leakage problems
The probable causes of each category are discussed in the following sections. A series of Trouble-
shooting Guides (decision trees) is also included at the end of the chapter to assist in identifying
some of the more common problems.
3.7.1 Ignition Failures
Ignition failure occurs when the ignition module fails to sense a flame within the 4-second time delay
period and locks out. When this happens, the module sends 24VAC through the interface board
alarm circuit to the controller/computer.
Analog controllers indicate ignition failure by illuminating the heat light and trouble light simultane-
ously. M100B and M2000 computers flash "
side that failed (in full-vat units, it will flash in the right window only).
The three primary reasons for ignition failure, listed in order of probability, are:
1. Problems related to the gas and/or electrical power supplies
2. Problems related to the electronic circuits
3. Problems related to the gas valve.
PROBLEMS RELATED TO THE GAS AND/OR ELECTRICAL POWER SUPPLIES
The main indicators of this are that an entire battery of fryers fails to light and/or there are no indi-
cator lights illuminated on the fryer experiencing ignition failure. Verify that the quick disconnect
fitting is properly connected, the fryer is plugged in, the main gas supply valve is open, and the cir-
cuit breaker for the fryer electrical supply is not tripped.
PROBLEMS RELATED TO THE ELECTRONIC CIRCUITS
If gas and electrical power are being supplied to the fryer, the next most likely cause of ignition fail-
ure is a problem in the 24VAC circuit. If the fryer is equipped with a built-in filtration system
(BIH52 models), first verify that the drain valve is fully closed. (The valve is attached to a mi-
croswitch that must be closed for power to reach the gas valve. Often, although the valve handle ap-
pears to be in the closed position, the microswitch is still open.) If the valve is fully closed, or the
fryer does not have a built-in filtration system, refer to the troubleshooting guides
SHOOTING THE 24VAC CIRCUIT.
Some typical causes of ignition failure in this category include a defective sensing wire in the ignitor
assembly, a defective module, a defective ignition wire, and a defective ignitor.
Occasionally you may encounter an ignition failure situation in which all components appear to be
serviceable and the microamp reading is within specification, but the unit nevertheless goes into
ignition failure during operation. The probable cause in this case is an intermittent failure of an
ignition module. When the unit is opened up for troubleshooting, the module cools down enough to
" in the display window on the
ignition failure
3-22
TROUBLE-