29733 R2 06/01/2003
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R7184 DETAILED SEQUENCE OF OPERATION
Power is applied to unit. The R7184 completes a self-diagnostic procedure. If no light or flame is present, and unit
passes its self-diagnostic procedure, the control enters into the idle mode.
Thermostat calls for heat:
A. Safety check is made for flame (4 second delay).
1. When flame is not present, the R7184 will apply power to the burner motor and igniter.
2. When flame is present, the control rem ains in the idle state.
B. Unit enters and completes a pre-purge period of 15 seconds, then applies power to the solenoid valve.
C. Control enters the trial for ignition state.
D. Control monitors the burner flame.
1. When flame is present, the control enters ignition carryover state. (Continues to spark for 10 sec.).
a. Provides continuous spark after flame is sens ed to assure that burner remains lit.
b. Turns on LED diagnostic light.
c. Starts carryover timer.
i Flame and call for heat are monitored.
· If flame is lost and lockout timer has not expired, R7184 will return to trial for ignition state.
· If flame is lost and lockout timer has expired, R7184 will enter the recycle state.
¨ Recycle timer starts.
¨ Burner motor and igniter and s olenoid valve are turned off.
¨ LED diagnostic light flashes slow.
¨ Returns to idle state when recycle timer expires (60 seconds).
E. Carryover timer expires.
i Enters run state.
· Igniter turns off.
Combustion continues until thermostat is satisfied, or R7184 detects a loss of flame and enters into Recycle Mode.
Thermostat is satisfied - call for heat is terminated:
· R7184 shuts off burner motor and solenoid valve.
· LED diagnostic light is off.
· R7184 returns to idle state.
Please see flow chart on page 26.
Appendix C TROUBLESHOOTING