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P 265-EP, P265F-EP, P250AF-EP
INTERMITTENT PILOT INSTRUCTION
FOR HONEYWELL SYSTEM
STARTING BURNER
1. Depress the gas valve control knob on the combination gas valve and turn to “OFF”. See Figure 9.
2. Set the room thermostat above room temperature and wait five (5) minutes.
3. Set thermostat below room temperature.
4. Turn gas control valve knob to “ON”.
5. Set room thermostat higher than room temperature so that the burner will start.
SHUTTING DOWN THE BURNER
1. Depress the gas valve control knob on the combination gas valve and turn to “OFF”.
2. Turn off electrical supply.
OPERATION
FIRST STAGE -- TRIAL FOR PILOT IGNITION
On every call for heat (system start), the S8600 performs an internal safe-start check. A system start is prevented if the
check shows that a flame-simulating condition is present..
During a normal start, the S8600 opens the first operator in the gas control. This allows gas to flow to the pilot burner.
Simultaneously, the electronic spark generator in the S8600 produces a 15,000 volt spark pulse output. This voltage produces a
spark at the pilot burner ignitor-sensor rod, igniting the gas flowing around the electrode. If the pilot flame is not detected during
the trial for pilot ignition, the S86E and F will continue trying for pilot ignition until a flame is established. The S86G and H
contain a safety locknut timer to limit the trial for pilot ignition period.
SECOND STAGE -- MAIN BURNER OPERATION
When the pilot flame is established, a flame rectification circuit is completed to the burner ground. The S8600 flame sensing
circuit detects the flame current and shuts the spark generator off. At the same time the second operator (main) is opened in
the gas control, allowing gas flow to the main burner. The pilot flame ignites the main burner conventionally. On the S86G and
H the flame current also holds the safety lockout timer in the reset, or normal, operating condition.
SAFETY LOCKOUT TIME (S8600 only)
The safety lockout timer circuit starts timing the moment the trial for pilot ignition starts. When the timing period runs out, the
trial for ignition ends, and the control module goes into lockout. Before another attempt to start can be made, the S8600 must
be reset. Reset by adjusting the thermostat or controller below room temperature, or to its “OFF” position. An alternate method
is to shut the system power “OFF”. Wait at least one (1) minute, then turn the system “ON”. If normal ignition does not occur,
use the troubleshooting table to determine the problem.
SERVICE
PRELIMINARY CHECK
The following visual checks should be made before troubleshooting and after installation or maintenance.
1. Check the power to the appliance and S8600.
2. Manual shutoff cocks in gas line to appliance must be open.
3. Make certain all wiring connections are clean and tight.
4. S86G, H module must not be in safety lockout. First de-energize the system and wait at least one(1) minute. This resets
the module, allowing a return to start condition.
5. Review the S8600 system normal sequence of operation.
SYSTEM TROUBLESHOOTING
Start the system by setting the thermostat or controller above required temperature. Observe system response. Establish
type of malfunction or deviation from normal operation. Use the S8600 Intermittent Pilot System Troubleshooting Table (Page
14) to check for normal system operation.
Use table by following instruction question in box. If the condition is true or okay (answers yes), go down to next box
underneath. If the condition is not true or not okay (answers no), go right to the next box alongside. Continue checking and
answering conditions in each box encountered, until a problem and/or the repair are explained. After any maintenance or repair,
the troubleshooting sequence should be repeated until the troubleshooting procedure ends with normal system operation.
