Vulcan-Hart VL2GSS, VL3GMS, VL2GMS, VL3GAS, VL2GAS Cook Cycle, Water Refill After Initial Fill

VL SERIES STEAMER - ELECTRICAL OPERATION

Cook Cycle

1.A Cook cycle should not be started, until the initial fill and preheat is completed, in order for the boiler steam pressure to be within operational limits.

A.Insert product into steamer.

B.Compartment door is closed and screw handle tightened down.

C.Compartment steam control arm is pulled forward and latches, allowing steam to enter compartment.

NOTE: Cool air and condensate exit through the steam exhaust solenoid valve (N.O.) until compartment temperature reaches 180°F.

D.Time is dialed on timer (past 5 minutes).

1)Micro switch SW1 contacts change state from N.C. to N.O.

2)Micro switch SW2 contacts also change state from N.C. to N.O.

E.Compartment power switch is turned ON.

1)L1 (HOT) to one side of the thermal switch.

NOTE: L2 (NEUTRAL) is connected to the other side of the buzzer, steam exhaust solenoid valve, trip solenoid, pilot light and timer motor.

F.Once compartment temperature reaches approximately 180°F thermal switch closes and supplies power L1 (HOT) to:

1)Steam exhaust solenoid valve (N.O.) energized and closes.

NOTE: Even though steam exhaust solenoid valve is closed, a small opening exists in the “guillotine” blade of the valve to allow “limited free venting” of condensate during a cook cycle.

2)Pilot light (red) comes on indicating timed cooking at 180°F has started.

3)Timer motor energized

2.Cooking Timer times down to approximately one minute before zero.

A.Micro switch SW2 contacts change state from N.O. back to N.C. (normal starting position).

1)Steam exhaust solenoid valve is de- energized and opens to exhaust steam and pressure from the compartment.

2)Steam trip solenoid is energized and unlatches steam control arm allowing it to return to the rear. Steam supply the compartment is shut off.

3.Cooking timer reaches zero.

A.Micro switch SW1 contacts change state from N.O. back to N.C. (normal starting position)..

4.Cooking timer is manually turned off.

5.Compartment power switch is turned OFF, buzzer is de-energized and power is removed from the common side of micro switch SW1.

6.Steamer reverts to preheat cycle until:

A.A cooking cycle is started. i.e. compartment door is closed and screw handle tightened down, time is dialed into timer (past 5 minutes) and the compartment power switch is turned ON.

B.Water level drops below low level cut-off probe.

C.Power switch is turned OFF.

NOTE: Burners will re-light after the boiler pressure drops below the low pressure set point limit (9 psi) and will stay on until the high pressure set point (11 psi) is reached. As long as steam pressure is within limits, even while cooking, burners can go off. The boiler is able to re-pressurize to the upper set point limit even with all compartments in cook mode.

NOTE: The cold water condenser thermostat remains closed and cold water condenser solenoid stays energized while cooking. If main water is shut off after boiler fill, then no cold water is present to condense steam/hot water and steam vapors exit the floor drain.

Water Refill (After Initial Fill)

1.Water level drops below low level probe (LL).

A.Power is removed from terminal 2 on the water level control .

1)The inverse latching relay is de- energized, returning ILR-1 (N.O.) and ILR-2 (N.C.) contacts back to their original state.

B.HL relay is energized.

1)Contacts HL-3 close.

2)HL LED comes on.

3)Fill solenoid is energized and water flows into tank.

2.Water reaches LL (low level) probe.

A.Power to terminal 2 on the water level control is present but no switching occurs.

3.Water reaches high level probe.

A.The inverse latching relay of the water level control is energized, changing the state of ILR-1 (N.O.) and ILR-2 (N.C.) contacts.

B.HL relay is de-energized.

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