User guide
59
When operating control (A) calls for heat, it energizes main gas valves (B), starting burner operation.
Theburnerswilloperateuntiloperatingcontrol(A)issatised.Thehighlimitcontrol(C),willstopburner
operationincaseofexcessivesteampressure(steamboiler)orexcessiveboilerwatertemperature(waterboiler).
Low water cut-off (D) will stop burner operation if the water level in boiler drops below the lowest safe level.
The pilot safety switch (E), connected to main gas valve (B), prevents operation of the main burners in case the
pilotamebecomesextinguished.Pilotsafetyswitch(E)providefor100%shut-offofgassupply.
FIG. 50
WIRING DIAGRAM - 5006B THRU 5014B SECT. BOILERS
THERMOCOUPLE CONTROL SYSTEM
CANADA ONLY
SECTION IV - OPERATION (continued)










