HGC4832

Overview

The Hobart HGC4832 is a gas conveyor oven in Hobart’s HGC Series. The manual identifies this model as ML-126185 and describes a conveyor belt that carries food through the oven tunnel. Operators set the cook time using a range switch and time knob, and the belt speed changes with the selected time. The oven’s power switch starts the oven, and ignition occurs automatically.

The HGC Series manual provides installation and operating guidance for the HGC4832, including gas and electrical requirements, ventilation information, cleaning procedures and troubleshooting. Its cooking chart includes examples for products such as burritos, nachos, souffles, omelettes and quiches.

Key Features

• Conveyor cooking: A powered belt moves products through the oven tunnel. The belt switch starts or stops the conveyor.
• Adjustable cook time: Select a time range of 2 to 8 minutes, 8 to 15 minutes or 15 to 20 minutes, then use the time knob to set the desired time on the display.
• Automatic ignition: Switching the oven on initiates ignition. The burner control automatically ignites and monitors the pilot flame.
• Temperature display and adjustment: The display shows actual oven cavity temperature. The set point can be read and adjusted using the set point control.
• Adjustable end baffles: A baffle at each end of the oven can be raised or lowered to accommodate product height.
• Top and bottom air distribution panels: These regulate the quantity of air directed to the top and bottom of the product. The manual says they are factory-adjusted and that further adjustment should be done by a Hobart authorized servicer.

Specifications

• Manufacturer and model: Hobart HGC4832 gas conveyor oven.
• Model number: ML-126185.
• Series: HGC Series gas conveyor ovens.
• Electrical service: 120 volts and 20 amps; a 20-amp receptacle and service are required for proper operation.
• Gas inlet: 3/4-inch inlet at the rear of the oven on the lower right side.
• Gas supply pressure stated in the manual: 7 inches water column (1.75 kPa) for natural gas and 11 inches water column (2.75 kPa) for propane gas.
• Factory temperature setting stated for HGC Series operation: 525°F (273°C).
• Cook-time ranges: 2 to 8 minutes, 8 to 15 minutes, or 15 to 20 minutes.
• Parts identification: The parts manual lists conveyor assembly 00-425577-000G1 for model ML-126185.

Installation & Requirements

Qualified installation and site planning

The manual says it is prepared for personnel qualified to install gas equipment, who should perform initial field start-up and adjustments. Before installation, verify that the electrical service and gas type—natural gas or propane—match the oven’s rating plate. The rating plate is on the right front side panel. If the supply does not match the equipment requirements, the manual says not to proceed and to contact a Hobart service representative.

Provide clearance of at least 2.5 inches (63.5 mm) from combustible and non-combustible construction at the sides and rear, and at least 36 inches (914.4 mm) at the front. The manual also calls for adequate space for servicing and operation, and says not to obstruct combustion or ventilation air openings. The oven can pass through a 34-inch (86 cm) doorway when the crate is turned on its side, or a 30-inch (76 cm) doorway without the crate. Check the access route before moving the unit.

Ventilation

The manual specifies that the ventilation hood should extend at least 6 inches (152 mm) past the oven at the front, back and each side of the conveyor belt. It states approximate exhaust requirements of 1,500 CFM for a single oven and 2,000 CFM for double-stacked ovens. Make-up air should be 65% to 80% of the exhaust air rating. Do not allow fans to blow directly at the oven; the manual also advises avoiding open windows next to the oven and wall-type fans that create cross-currents.

Gas and electrical connections

Connect the gas supply to the 3/4-inch inlet at the rear, lower right side of the oven. The manual requires a gas shutoff valve in the gas line ahead of the oven and says gas connections and pipe joint compound must be resistant to propane. Check gas-supply joints for leaks with a soap-and-water solution, never an open flame, and purge gas piping of air before lighting. The gas line pressure figures in the specifications are the manual’s stated store-line pressures.

The oven is supplied with a power cord for 120-volt, 20-amp service. The manual requires a properly grounded three-prong receptacle and says not to remove the grounding prong. Electrical and grounding connections must comply with applicable electrical codes. For Canadian installations, the manual cites local codes, CAN/CGA-B149.1 for natural gas, CAN/CGA-B149.2 for propane and the Canadian Electrical Code, CSA C22.2 No. 3.

For ovens mounted on casters, the manual specifies the supplied casters, a compliant connector and quick-disconnect device, and a restraint to prevent strain from being transmitted to the connector. If the restraint must be disconnected, shut off the gas first and reconnect the restraint before restoring the gas supply. Stacked ovens require no fasteners between the units; the upper oven’s weight holds it in place. Casters are non-adjustable, so the oven should be installed on a level floor.

Operation

Starting and setting the oven

1. Turn the gas combination valve to ON.
2. Push the power switch to ON. The burner control initiates automatic ignition.
3. Set the oven temperature to the desired temperature. In the manual’s operating instructions, the oven starts at the factory setting of 525°F (273°C), and the display shows actual cavity temperature.
4. Select the desired cook-time range: 2 to 8, 8 to 15 or 15 to 20 minutes. Turn the time knob clockwise to increase cook time or counterclockwise to decrease it until the desired time appears on the display.
5. Turn the belt switch ON to start the conveyor. Place products or utensils on the entrance end of the belt, not inside the oven tunnel. Remove them after they have completely cleared the tunnel.

To read or change the set point, use the set point control as described in the manual. On the control version with a Read Set Point button, press and hold the button to display the set point while turning the Set Point knob to the desired temperature; release the button afterward. The manual identifies cycle time, manual reset and prop band as service controls and says not to touch them.

To turn the oven off, set the power switch to OFF. For an extended shutdown, also turn the gas combination valve and the main gas shutoff valve to OFF. If the burner does not light within 90 seconds, the burner control shuts off the gas valve and locks out. Switch the power OFF and then ON to reset it. If it still fails to light, turn the oven off and wait 5 minutes before trying again. If lockout occurs again, contact a Hobart authorized servicer.

Conveyor and product adjustment

If the conveyor stalls, the time display shows “O.L.” and the belt stops automatically. Remove the blockage, then move the belt switch up and down to reset the control. The time should reappear on the display and the drive motor should restart. The end baffles can be adjusted for product height: loosen the two thumb screws using insulated gloves, reposition the baffle and retighten the screws. The top and bottom air distribution panels regulate airflow around the product; have a Hobart authorized servicer make adjustments to these panels.

Cleaning & Maintenance

Disconnect electrical power before cleaning. The manual warns that the oven and its parts can be hot, so use care when operating, cleaning or servicing it. Clean the exterior daily with a clean, damp cloth and wipe it dry with a soft, clean cloth. Avoid abrasive powders and pads, which can damage the finish. Clean the right- and left-hand crumb trays. Do not hose down the oven, and do not use it if its controls have become wet; contact a Hobart servicer if the controls are wet.

Clean the intake fans and slots on the back of the oven and control box weekly using a long-bristle brush. The manual warns that obstructions in these areas may cause motor damage. It also says the oven should be inspected at least annually by a Hobart authorized servicer. More frequent cleaning may be required because of grease vapours, dust or similar conditions. Keep the control compartments, burners and circulating-air passageways clean.

The manual includes procedures for removing the conveyor belt and conveyor assembly for cleaning. For belt removal, it directs the operator to remove the end-of-track screws, locate and remove the belt’s splicing strands, then reverse the procedure to reinstall the belt. For conveyor assembly removal, first remove the crumb trays and the cover where the conveyor shaft enters the left-hand control box; lift the drive end and slide the assembly into the tunnel to relieve tension on the drive chain, slip the chain off the drive sprocket and pull the assembly out. The manual directs operators to reverse the steps to reinstall it. Install the belt with its closed loop end facing the direction of travel.

Troubleshooting

The manual’s troubleshooting guide covers an oven that will not operate, a burner that is on while the oven does not start, an “O.L.” speed-control display, a conveyor belt that does not turn or jumps, burner ignition failure, uneven cooking, gas odours, the temperature controller being on while the burner goes off, and excessive circulating-motor vibration.

• Conveyor stall or “O.L.” display: The belt stops automatically. Remove the blockage and cycle the belt switch up and down to reset the control.
• Oven does not operate: The troubleshooting list identifies the gas combination valve being OFF, an improperly adjusted temperature controller or a thermocouple problem as possible causes.
• Belt or speed-control issues: The guide lists a stuck conveyor belt, a speed-control problem, a loose gear and a loose chain among possible causes.
• Ignition trouble: The guide lists the gas combination valve being OFF and a problem with the centrifugal switch or gas valve among possible causes. Follow the lighting reset steps above; if the burner locks out again, contact a Hobart authorized servicer.

For service and parts information, the manual directs users to their local Hobart Service Office.

Applications

The HGC Series cooking chart gives reference settings for several products. It lists burritos and enchiladas at 2.5 to 3.5 minutes and 475°F (246°C), and assorted nachos at the same time and temperature. Souffles and omelettes are listed at 5.5 to 6.5 minutes and 510°F (265°C), while quiches are listed at 9 to 10 minutes and 390°F (199°C). These are chart examples from the manual; adjust settings to suit the product and operating requirements.