Vulcan-Hart MHB24G, VHX24G5 manual Fill and Cold Water Solenoid Valves, Small increments

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VHX SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS

Mechanical Pressure relief valve factory set to approximately 15 PSI. If the pressure in the boiler reaches this level, the valve will OPEN.

A.High pressure light (amber) will come ON.

1)If the pressure switch opens at a pressure range other than 14.5 to 15.0 PSI then an adjustment to the switch setting should be made.

a.Proceed to step 5.

CAUTION: While making the adjustment, do not press on the wheel with extreme force. The switch may rotate and develop a leak at the compression fittings or in some cases, the rear lead wire may touch the control box and create an electrical short.

5.Turn the adjustment wheel several clicks to change the pressure switch set point.

A.A counterclockwise rotation lowers the pressure switch set point while a clockwise rotation raises the pressure switch set point.

NOTE: For every click of the adjustment wheel during rotation, the pressure setting is changed approximately 1/8 PSI. Make the adjustment

in small increments.

6.Raise the handle on the 15 PSI mechanical pressure relief valve and open the valve for approximately 4 minutes. This will exhaust steam down the drain line and lower the boiler pressure.

A.High limit pressure switch closes at approximately 12 PSI (non-adjustable).

1)Press the reset switch to reset the High Pressure safety control.

a.High pressure light (amber) goes out.

B.Lower the boiler pressure to approximately 8 PSI.

C.Ignition sequence starts, main burner lights and water in the boiler begins to heat.

7.Repeat steps 4 through 6 until the High Limit Pressure Switch opens at the correct pressure.

8.If the 13 PSI pressure relief valve (PRV- left side) was temporarily disabled as outlined in step 1:

A.Turn the power switch OFF and allow the boiler to blowdown.

B.Return the valve to its original state.

9.Check steamer for proper operation.

FILL AND COLD WATER

SOLENOID VALVES

WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.

1.Check to ensure the solenoid valve is receiving power.

A.If the solenoid valve is receiving power but the valve is not opening, the coil may be malfunctioning.

1)Remove the lead wires from the solenoid coil and check for continuity.

a.If continuity is measured, proceed to step "1. B.".

b.If no continuity is measured, replace the solenoid valve and check for proper operation.

B.If the solenoid valve is receiving power and the valve appears to be opening but little or no water is flowing through it, then the valve ports may be clogged with debris or a valve component malfunctioning.

2.To check solenoid valve further, proceed to step 3 through 8 for disassembly and inspection of internal components.

3.Shut water supply off, disconnect the water line from the valve body then remove the solenoid valve from the steamer.

4.Remove the coil assembly from the valve stem by lifting up on the retaining cap at the top of the solenoid valve and sliding the metal cover plate off.

5.Clamp the body of the valve in a vise.

6.Mark a scribe line on the stem nut to the valve body for proper re-tightening.

7.Remove the stem locking nut to remove the stem from the valve body.

8.All parts are now accessible for inspection and cleaning.

NOTE: If internal solenoid parts appear to be damaged or worn, then replace the solenoid valve. Do not reuse damaged or worn parts. No internal solenoid parts are available as a service replacement.

A.Check rubber seal on bottom of plunger.

B.Check plunger spring.

C.Check O-ring in valve body.

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 Conditioning Specifications SystemWater Supply ElectricalTools Gas SupplyStandard SpecialSteamer Operation Cabinet Base BoilerCooking Compartment Controls VHX Series Steamers OperationBoiler Blowdown Steamer Shut OFF Component Function VHX Series Steamers Component FunctionBlowdown/Drain Ignition Control ModuleSteam Header Assembly Water LevelWater Inlet Valve manual Pressure Relief ValveCompartment Pressure Switch Steam Solenoid ValveManifold Pressure Gauge Steam Supply ManifoldRemoval and Replacement of Parts VHX Series Steamers Removal and Replacement of PartsComponent Locations 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 HandleService Procedures and Adjustments Clean-OutBoiler 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 Intake Shut-Off Valve Adjustment Steam Flow Door Sealing AdjustmentCooking Compartment 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 LegendBoiler Operational Status LED Indicator Reset Engaged State CInitial Conditions State a Aux Water Level Satisfied State BAir Pressure Switch Satisfied State D K32 CloseK51 Close Burner ON, Boiler Heating to generate steam State ESequence of Operation NEW Style Controls BoilerInitial Fill and Preheat 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