Vulcan-Hart VL3GAS, VL3GMS, VL2GMS, VL2GAS, VL2GSS, VL3GSS, VL3GPS Sequence Of Operation, Gas Models

VL SERIES STEAMER - ELECTRICAL OPERATION

SEQUENCE OF OPERATION

GAS MODELS

This sequence of operation is written for steamers with electronic ignition, solid state water level controls, CSD-1 (code) boiler controls option and with Prevent cooking compartment controls. Refer to schematic diagram numbers 3928 and 3929 for a boiler control schematic and 3962 for a schematic and wiring diagram on Prevent cooking compartment controls.

Initial Fill and Preheat

1.Conditions.

A.Power switch OFF.

B.Ignition module reset switch ON

C.Cooking timers off.

D.Compartment power switches OFF.

E.Unit connected to correct voltage .

1)L1 (HOT) to one side of the cooking compartment controls; to one side of the cold water condenser thermostat; to one side of the power ON/OFF switch.

2)L2 (NEUTRAL) to one side of the cooking compartment controls; to one side of the cold water condenser (CWC) solenoid valve; to one side of the power ON/OFF switch.

F.Unit properly grounded. (Boiler and water level control share a common ground)

G.Water supply valve on.

H.Gas supply valve on.

I.Gas combination control valve ON.

J.Control (cycling) pressure switch closed.

K.High limit pressure switch closed.

L.Cold water condenser (CWC) thermostat open.

M.Blowdown solenoid valve (drain) open and boiler empty.

N.Compartment doors open.

2.Power switch turned ON. (located on boiler control box)

A.Power switch indicator light (red) comes on.

B.Hi pressure indicator light (amber) comes on.

C.Low water level indicator light (amber) comes on.

NOTE: The high pressure indicator light will remain on and the safety circuit de-energized until boiler steam pressure is within operational limits (high limit pressure switch closed) and the manual reset button is pressed. The low water indicator light will remain on and the safety circuit de-energized until the water level in the boiler reaches the low level cut-off probes (minimum level) for the water level control, the auxiliary low level cut-off control and the manual reset switch is pressed. The gas burners will not light until these conditions are satisfied.

D.Water level control (WLC) is powered.

1)High level (HL) relay is energized, HL-3 (N.O.) contacts close and HL LED lights up.

2)The inverse latching relay of the board remains de-energized, leaving the ILR-1 (N.O.) and ILR-2 (N.C.) contacts in their shelf state.

E.Auxiliary low water level cut-off control is powered, LLCO-2 (N.O.) contacts remain open.

F.With the HL-3 and ILR-2 contacts closed, the fill solenoid is energized and water boiler begins filling.

G.Blowdown solenoid valve is energized and closes.

H.Ignition module begins sparking to light pilot after a 3 second delay.

1)If pilot ignition is established (pilot lit) then a micro amp flame sense current is sent back to the ignition control module through the ignition cable. Sparking stops, pilot remains lit and is ready to ignite burners.

2)If pilot ignition is not established after 90 seconds, sparking stops and the ignition control module locks out power to the combination gas valve (pilot valve and main valve remain closed). The module remains locked out until the reset switch on the ignition control module box is switched to OFF then ON to re-start the ignition trial cycle.

NOTE: If the modules re-set switch is in the OFF position, no sparking will occur or if it’s turned OFF while idling or cooking, then pilot and burners will go out and not re-ignite upon call for heat by the cycling pressure switch.

Page 42 of 88