Vulcan-Hart MHB24G, VHX24G5 manual VHX Series Steamers Component Function, Blowdown/Drain

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VHX SERIES STEAMERS - COMPONENT FUNCTION

COMPONENT FUNCTION

CABINET BASE BOILER CONTROLS

Power Switch (ON/OFF) . . . . . . . . .

Reset Switch (Manual) . . . . . . . . . .

Boiler Fill Solenoid Valve . . . . . . . .

Cold Water Condenser

Solenoid Valve . . . . . . . . . . . . . . . . .

Blowdown/Drain

Solenoid Valve . . . . . . . . . . . . . . . . .

Cycling Pressure Switch . . . . . . . . .

High Limit Pressure Switch . . . . . .

Main Water Level Control . . . . . . . .

Auxiliary Water Level Control . . . . .

Transformer . . . . . . . . . . . . . . . . . . .

Ignition Control Module . . . . . . . . .

Main Gas Valve . . . . . . . . . . . . . . . .

Pilot Gas Valve . . . . . . . . . . . . . . . .

Combustion Blower . . . . . . . . . . . .

When turned ON, supplies power to the control circuit.

Resets the low water level safety circuit on initial startup or the occurrence of a low water condition and allows the boiler to fill with water. Also, resets the high pressure level safety circuit on initial startup or the occurrence of a high pressure condition and allows the gas ignition cycle to start.

Admits water to the boiler when demanded by the water level control to maintain the correct water level in the boiler.

Allows cold water flow into the boiler blowdown drain box to condense steam and cool the hot water before its discharge into the drain.

A normally open valve (N.O.) that closes to allow boiler to fill and pressurize when power switch is turned ON and opens when power switch is turned off to blowdown and drain the boiler. This valve is plumbed into the drain line of the boiler.

Controls boiler pressure between prescribed limits by turning the heat source on and off.

Protects the boiler from pressures above 15 psi by removing power from the heating circuit. This pressure setting is higher than the cycling pressure switch in order to turn off the heat source before the boiler pressure reaches its limit. After the pressure drops below approximately 12psi, press the rest switch of the front control panel to rest the safety circuit.

A dual functioning control that allows water to fill and maintain the proper level in the boiler providing differential water level control; and shuts off the main gas valve if the water level drops too low providing low level cut-off protection. The water level control works by using three different probe lengths to monitor the water level. The probes consist of a high level (HL), low level (LL) and low water cut-off (LLCO).

A back up to the low level cut-off on the main control. Protects the boiler and heating system components from a low water cut-off condition by opening the 24VAC voltage path to the heating system circuit. Also, energizes the low water "light" on the front control panel.

Provides 24VAC power to ignition control module and heating circuit.

Controls and monitors gas heating. Energizes pilot valve coil to supply gas to pilot, generates spark to ignite gas at the pilot, monitors the presence of flame and energizes the main and pilot valve coils on the main gas valve upon a call for heat.

A gas solenoid valve that opens to allow gas flow to the main burner after the successful ignition of the pilot burner when a call for heat is made.

A gas solenoid valve that opens to allow gas flow to the pilot to ignite the main burner when a call for heat is made. The valve is energized by a time delay circuit on the relay board during ignition trial for approximately 15 seconds. New style controls only.

Provides forced air to the gas/air mixture for gas pilot and main burner combustion.

F24700 (October 2001)

 

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Contents VHX Boiler Base Series High Efficiency GAS Steamers VHX24G ShownTable of Contents VHX Series Steamers Maintenance Cleaning Introduction InstallationGeneral Boiler Control Styles Water Supply Water Conditioning SpecificationsSystem ElectricalStandard ToolsGas Supply SpecialCooking Compartment Controls Steamer OperationCabinet Base Boiler VHX Series Steamers OperationBoiler Blowdown Steamer Shut OFF Blowdown/Drain Component FunctionVHX Series Steamers Component Function Ignition Control ModuleWater Inlet Valve manual Steam Header AssemblyWater Level Pressure Relief ValveManifold Pressure Gauge Compartment Pressure SwitchSteam Solenoid Valve Steam Supply ManifoldComponent Locations Removal and Replacement of PartsVHX Series Steamers Removal and Replacement of Parts Cabinet Base Boiler ControlsCabinet Base Boiler Controls Relay Board Water Level Controls Main or Auxiliary LlcoCooking Compartment Controls Pressure Switches Water Level Gauge AssemblyBoiler Assembly Pilot GAS Valve Main GAS Valve Boiler Fill and Cold Water Condenser Solenoid ValvesBurner Head Assembly Complete Burner AssemblyHeat Exchanger VHX Series Steamers Removal and Replacement of Parts Removal Cooking Compartment DoorsGasket Latch Assembly HandleBoiler Service Procedures and AdjustmentsClean-Out InspectionWater Level Probe Housing Blowdown Descaler Cathodic ProtectorWater Level Controls TestAuxiliary Low level Cut-Off Control High Limit CyclingFill and Cold Water Solenoid Valves Small incrementsInline Water Strainer Cleaning Boiler BLOWDOWN/DRAIN Solenoid ValvePressure Switch Adjustment Main Burner Ignition ChecksGAS Manifold Pressure Adjustment VHX Series Steamer Service Procedures and Adjustments AIR Pressure Switch Adjustment GAS Pilot Pressure Adjustment Pressure Readings Inches W.C GAS Manifold Pressure Adjustment Ignition Control Module Checks TerminalsSpark Verification Test Cooking Compartment Intake Shut-Off Valve Adjustment Steam FlowDoor Sealing Adjustment Cooking Compartment DoorsDoor Latch Adjustment VHX Series Steamer Electrical OperationElectrical Operation Low Level Cut-Off & Differential ControlAuxiliary Low Level Cut-Off Board Layout and LED Legend LED LegendInitial Conditions State a Boiler Operational Status LED IndicatorReset Engaged State C Aux Water Level Satisfied State BK51 Close Air Pressure Switch Satisfied State DK32 Close Burner ON, Boiler Heating to generate steam State EInitial Fill and Preheat Sequence of OperationNEW Style Controls Boiler HL-LEDN9, N10, N11, N12, N13 go out N14, N16, N17 go outWater Refill After Initial Fill Boiler Blowdown/drainVHX Series Steamer Electrical Operation Cooking Compartment Controls This page Intentionally Left Blank Schematics Models Built After 5/25/00 New Style Boiler ControlsVHX Series Steamer Electrical Operation Models Built Before 5/25/00 Old Style Boiler Controls Cooking Compartment Controls Wiring Diagrams VHX Series Steamer Electrical Operation Models Built Before 5/25/00 Old Style Boiler Controls VHX Series Steamer Electrical Operation Cooking Compartment Controls VHX Series Steamer Troubleshooting TroubleshootingBoiler Base Controls Symptom Possible Causes Adjustments Boiler blowdown solenoid valve clogged and not fully closing Boiler Base Procedures and Adjustments VHX Series Steamer VHX Series Steamer Condensed Spare Parts List Condensed Spare Parts ListNEW Style Controls only VHX24G, VHX24G5, MHB24G
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