Vulcan-Hart ML-135503, ML-135504, GHF91G, GHF90G Electrical Operation, Control System Description

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ELECTRICAL OPERATION

CONTROL SYSTEM DESCRIPTION

1.The thermopile (TP) provides the total control voltage for this system.

A.One side of the thermopile is connected to the common (C) of the high limit (HL).

B.The other side of the thermopile is connected to the normally open (NO) contacts of the high limit.

C.The common of the high limit (below the high limit trip temp.) is connected through the normally closed (NC) contacts of the high limit, through wire 3 to the combination valve pilot connection common.

D.The other side of the pilot valve is connected through wire 4 to wire 1 to the high limit normally open contacts which hold the pilot valve open.

1)If the high limit trips, connection is made from the common to the normally open contacts, turning off pilot valve voltage. The gas valve closes.

2.Thermostat Control.

A.One side of the millivolt supply is connected through the high limit system, as described above, to the thermostat common (wire 3) of the combination valve.

B.The other side of the thermopile is connected from the normally open contacts of the high limit to the thermostat through wire 1.

C.When the thermostat calls for heat (closed circuit) power from the thermopile is then connected to the other combination valve thermostat connection through wire 2.

D.If the high limit trips, the thermopile is connected across zero ohms, the output voltage of the thermopile drops to 0.0 millivolts, and the thermostat coil of the combination valve drops out, shutting the thermostat valve.

3.Total Shutdown.

A.When the high limit trips, 0.0 millivolts will read across both coils of the combination valve, causing both valves to close.

B.Pilot relight cannot be accomplished until oil cools sufficiently to allow high limit to close.

C.If any wire in the system is cut or broken, the system will shut down.

SYSTEM CONDITION QUICK CHECK

PROCEDURES

1.Use the Pilot Lighting procedure and check millivolts (mV) at wires 3 and 4.

A.If the pilot lights, then pilot combination and high limit are good.

B.If the pilot will not stay lit, check high limit and open the thermopile circuit. It should read 300 mV; if there are Ø volts, check high limit. If the high limit is good, replace combination valve.

C.Check for voltage at disconnected thermopile. It should read 300 mV; if there are Ø volts, replace thermopile. Check high limit. If the high limit is good, replace combination valve.

2.Turn on thermostat; burners should light.

A.If the burner does not light, check the following:

1)Voltage at combination valve at wires 2 and 4.

2)If correct voltage is present, then check combination valve.

3)If there are Ø volts, check voltage between wire 3 of combination valve and wire 1 of thermostat. If correct voltage is present, then check resistance of thermostat and wire 32. If there is no voltage, check resistance of wire 1 to normally open contacts of high limit.

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Contents GHF Series Heavy Duty Range Matching GAS Fryers & Frymates Table of Contents Specifications GeneralIntroduction ToolsRemoval and Replacement of Parts Covers and PanelsBurners DoorThermostat High Limit ThermopilePilot Orifice Combination ValveFRY Tank Service Procedures and Adjustments Millivolt Controls TestThermostat Calibration Calibration StepsPilot Adjustment BURNERS, Nozzles and OrificesBurners Nozzles and OrificesCombination Valve Regulator Adjustment System Condition Quick Check Procedures Electrical OperationControl System Description Schematic Component Function Troubleshooting Symptom Possible CauseTroubleshooting Form 35618

GHF90G, GHF91G, ML-135504, ML-135503 specifications

The Vulcan-Hart ML-135503, ML-135504, GHF91G, and GHF90G are renowned appliances designed to cater to the rigorous demands of commercial kitchens. These models are celebrated for their reliability, efficiency, and advanced features that enhance cooking performance.

The ML-135503 and ML-135504 models are equipped with powerful gas cooking capabilities. They feature heavy-duty cast iron grates that provide durability and excellent heat retention. The adjustable burners allow chefs to control the flame intensity with precision, ensuring that every dish is cooked to perfection. The ergonomic design of the controls enhances user experience, allowing for easy operation even in fast-paced kitchen environments. Another notable feature is the built-in drip trays that simplify cleanup, making these models not only functional but user-friendly.

On the other hand, the GHF91G and GHF90G series serve as ideal solutions for high-volume cooking requirements. These units are engineered with advanced technologies that ensure even heat distribution, allowing for consistent cooking results. The GHF series boasts a robust construction, designed to withstand the rigors of daily use in busy kitchens. Equipped with features such as adjustable thermostats and turbo broil burners, these models facilitate precise temperature control, which is critical for various cooking techniques.

In terms of energy efficiency, Vulcan-Hart has integrated features into the GHF91G and GHF90G to reduce gas consumption while maintaining high performance. This not only contributes to lower operational costs but also aligns with sustainable practices in the food service industry. Furthermore, both series prioritize safety, featuring pilot lights and flame failure devices that enhance operational security.

Overall, the Vulcan-Hart ML-135503, ML-135504, GHF91G, and GHF90G models stand out in the commercial kitchen equipment market due to their exceptional build quality, advanced technologies, and user-oriented features. Chefs and restaurateurs can rely on these appliances to deliver consistent performance, making them invaluable assets in any culinary establishment. Whether it’s grilling, frying, or simmering, these models exemplify Vulcan-Hart's commitment to innovation and excellence in kitchen solutions.
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