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Problems that are likely to be encountered can be grouped into five broad categories:
1. Ignition failures
2. Improper burner functioning
3. Improper temperature control
4. Computer-related problems
5. Autofill System problems.
The probable causes of each category are discussed in the following sections.
Troubleshooting Guides (decision trees) is also included at the end of the chapter to assist in
identifying some of the more common problems.
6.7.1 Ignition Failures
Ignition failure occurs when the ignition module fails to sense a flame within a 4-second time delay
period and locks out. When this happens, the module sends 24 VAC through the interface board
alarm circuit to the computer. The computer then displays help.
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 indicator of a problem with the electrical power supply is that there are no indicator lights
illuminated on the unit. The main indication of a problem with the gas supply is failure of the unit to
fire. Verify that the gas line quick-disconnect fitting (if used) is properly connected, the unit is
plugged in, the main gas supply valve is open, and the circuit breaker for the unit's electrical supply
is not tripped.
PROBLEMS RELATED TO THE ELECTRONIC CIRCUITS
If gas and electrical power are being supplied to the rethermalizer, the next most likely cause of
ignition failure is a problem in the 24 VAC circuit. First, verify that the drain valve is fully closed.
(The drain valve assembly includes a microswitch that must be closed for power to reach the gas
valve. Often, although the valve handle appears to be in the closed position, the microswitch is still
open.) If the drain valve is fully closed, refer to the troubleshooting guide
.
24 VAC 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, or a defective ignitor. Occasionally an
ignition failure situation may be encountered in which all components appear to be serviceable and
the microamp reading is within specification, but the unit nevertheless goes into ignition failure
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A series of
TROUBLESHOOTING THE
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Table of Contents
Troubleshooting
