Vulcan-Hart VL3GPS, VL3GMS, VL2GMS, VL3GAS, VL2GAS, VL2GSS, VL3GSS, VL2GPS service manual Cook Cycle

VL SERIES STEAMER - ELECTRICAL OPERATION

	NOTE: Power the internal contactors on			1) Boiler pressurizes to 15 PSI, causing
	the low level cut-off and auxiliary low level			the high limit pressure switch to open.
	cut-off will remain, until the water level			At that time, the auxiliary heating
	drops below the LLCO probes or the power			element contactor(s) are de-
	switch is turned OFF.			energized, shutting off power to the
4.	Manual reset switch is pressed (momentary).			heating elements. The pressure
				switch will remain open until the
	A. The auxiliary heater contactor is energized			pressure drops below the lower limit
	supplying power to the heating elements			set point of 6 PSI. Boiler water level
	and the heat light (amber) comes on.			drops below the LLCO (low water
	1) Water in boiler heats up.			level cut-off) probes for the low level
				cut-off and the auxiliary low level cut-
	B. Internal relay on manual reset switch is			off controls, de-energizing the internal
	energized.			contactor on both controls. This de-
	1) Normally open contacts close and			energizes the main and auxiliary
				heater contactors, shutting off power
	lock to provide power to the auxiliary
				to the heating elements. The heating
	heater contactor and the heat light
				elements will remain off until the
	after the reset switch is released.
				water level rises above the LLCO
5. Water reaches LL (low level) probe.				probes and the manual re-set switch
	A. Power to terminal 7 on the differential			is pressed.
			COOK CYCLE
	level control is present but no switching
	occurs.		1. A Cook cycle should not be started, until the
6. Water reaches HL (high level) probe.
			initial fill and preheat is completed, in order for
	A. Power to terminal 10 on the differential		the boiler steam pressure to be within
			operational limits.
	level control.
			A.	Insert product into steamer.
	1) The internal contactor coil on the
	differential level controls is energized.		B. Compartment door is closed and screw
	a. The normally closed contacts on			handle tightened down.
	terminals 3 and 4 open, de-		C. Compartment steam control arm is pulled
	energizing the boiler fill solenoid			forward and latches, allowing steam to
	and the boiler stops filling.			enter compartment.
	NOTE: The internal contactor coil has a		NOTE: Cool air and condensate exit through
	locking path through contacts on terminals		the steam exhaust solenoid valve (N.O.) under
	7 & 8 to the low level probe to keep the		“Full Free Venting” until the compartment
	coil energized after the water level drops		temperature reaches 180°F. When the solenoid
	below the high level probe.		valve energizes and closes, condensate will
7.	Boiler steam pressure reaches upper limit set		continue to exhaust through a small opening
			the valve under “Limited Free Venting” until the
	point of 11 PSI. (Approximately 15 min.)
			solenoid valve de-energizes and re-opens, one
	A. Cycling pressure switch opens, heater
			minute before the end of a cook cycle.
	contactor(s) de-energize and power to the		D.	Time is dialed on timer (past 5 minutes).
	heating elements is removed.
				1) Micro switch SW1 contacts change
	NOTE: Steam should not be seen entering a
				state from N.C. to N.O.
	compartment until the manual steam control
				2) Micro switch SW2 contacts also
	arm is pulled forward and locked.
8.	Boiler steam pressure drops below lower limit			change state from N.C. to N.O.
			E.	Compartment power switch is turned ON.
	set point of 9 PSI and the cycling pressure
	switch closes.			1) L1 (HOT) to one side of the thermal
	A. Boiler steam pressure is maintained by the			switch.
	cycling of the pressure switch between the			NOTE: L2 (NEUTRAL) is connected to the
	upper and lower set point limits. The
				other side of the buzzer, steam exhaust
	cycling pressure switch continues to
				solenoid valve, trip solenoid, pilot light and
	energize and de-energize the heating
				timer motor.
	element contactor(s), which in turn, cycles
	the heating elements on and off. This
	sequence continues until one of the
	following occurs:
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