Burnham 8H manual

2.Electronically Supervised Standing Pilot (OP) Sequence of Operation

a.Normal Operation

i.Thermostat or operating control calls for heat.

ii.Terminal #6 of RM7890C Burner Control is energized, initiating a microcomputer monitored circuit test.

iii.Pilot Flame Establishing Period (PFEP) begins.

iv.After pilot flame is proven, terminal #9 of

RM7890C is energized, allowing main gas flow and ignition of main burners. “Main” gas light will be illuminated.

v.Call for heat ends. Terminal #6 of RM7890C is de-energized, in turn de- energizing gas valves and extinguishing main flame. “Main” gas light is de- energized.

b.Safety Shutdown

i.Limit: Automatically interrupts main burner operation when water temperature exceeds set point. Maximum allowable temperature is 250°F. Circulator continues to operate with call for heat. Normal operation resumes when water temperature falls below set point.

ii.Blocked Vent Switch: Automatically interrupts main burner operation when excessive flue gas spillage occurs.

Circulator continues to operate with call for heat. If blocked vent switch is activated do not attempt to place boiler in operation. Correct cause of spillage and reset blocked vent switch.

iii.Flame Roll-out Switch: Automatically interrupts main burner operation when flames or excessive heat are present in vestibule. Circulator continues to operate with call for heat. Control is single use device. If flame roll-out switch is activated, do not attempt to place boiler in operation.

Correct cause of spillage and replace flame roll-out switch.

iv.RM7890C Burner Control: Automatically interrupts main burner operation if a pilot flame is not detected during the four or ten second pilot flame establishing period. The

RM7890C will lockout or recycle based on jumper settings. “Alarm” light will be illuminated. Refer to instructions supplied with RM7890C for additional control information.

3.Electronically Supervised Standing Pilot (OP-CSD-1) Sequence of Operation

a.Normal Operation

i.Thermostat or operating control calls for heat.

ii.Terminal #6 of RM7890C Burner Control is energized, initiating a microcomputer monitored circuit test.

iii.Pilot Flame Establishing Period (PFEP) begins.

iv.After pilot flame is proven, terminal #9 of

RM7890C is energized, allowing main gas flow and ignition of main burners. “Main” gas light will be illuminated.

v.Call for heat ends. Terminal #6 of RM7890C is de-energized, in turn de- energizing gas valves and extinguishing main flame. “Main” gas light is de- energized.

b.Safety Shutdown

i.Limit: Automatically interrupts main burner operation when water temperature exceeds set point. Maximum allowable temperature is 250°F. Circulator continues to operate with call for heat. Normal operation resumes when water temperature falls below set point.

ii.Blocked Vent Switch: Automatically interrupts main burner operation when excessive flue gas spillage occurs.

Circulator continues to operate with call for heat. If blocked vent switch is activated do not attempt to place boiler in operation. Correct cause of spillage and reset blocked vent switch.

iii.Flame Roll-out Switch: Automatically interrupts main burner operation when flames or excessive heat are present in vestibule. Circulator continues to operate with call for heat. Control is single use device. If flame roll-out switch is activated, do not attempt to place boiler in operation.

Correct cause of spillage and replace flame roll-out switch.

iv.RM7890C Burner Control: Automatically interrupts main burner operation if a pilot flame is not detected during the four or ten second pilot flame establishing period. The

RM7890C will lockout or recycle based on jumper settings. “Alarm” light will be illuminated. Refer to instructions supplied with RM7890C for additional control information.

v.Pilot Safety Switch: Automatically de- energizes main gas valve and interrupts pilot gas supply if pilot flame is not detected at any time.

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