Hobart HGSO Series Gas Bake & Roast Ovens

Important Safety Information

WARNING: THE OVEN AND ITS PARTS ARE HOT. USE CARE WHEN OPERATING, CLEANING OR SERVICING THE OVEN.

This manual is prepared for personnel qualified to install gas equipment. They should perform initial field start-up and adjustments.

Post instructions for gas detection in a prominent location. Information can be obtained from the local gas supplier.

Important Gas Detection Procedure

IN THE EVENT A GAS ODOR IS DETECTED, SHUT DOWN UNITS AT MAIN SHUTOFF VALVE AND CONTACT THE LOCAL GAS COMPANY OR GAS SUPPLIER FOR SERVICE.

For Your Safety

DO NOT STORE OR USE GASOLINE OR OTHER FLAMMABLE VAPORS OR LIQUIDS IN THE VICINITY OF THIS OR ANY OTHER APPLIANCE.

WARNING: IMPROPER INSTALLATION, ADJUSTMENT, ALTERATION OR MODIFICATION, SERVICE OR MAINTENANCE CAN CAUSE PROPERTY DAMAGE, INJURY OR DEATH. READ THE INSTALLATION, OPERATING AND MAINTENANCE INSTRUCTIONS THOROUGHLY BEFORE INSTALLING OR SERVICING THIS EQUIPMENT.

IN THE EVENT OF A POWER FAILURE, DO NOT ATTEMPT TO OPERATE THIS DEVICE.

General Information

The Hobart Model HGSO Series Gas Bake and Roast Ovens are constructed with multiple heat ducts for controlled and even heat distribution. All ovens are equipped with legs and adjustable feet, or can be mounted on a solid base.

Interior and exterior parts are removable for easy cleaning or replacement.

Optional equipment includes an inspection window, oven light, steam injector nozzles for baking hard crust breads, and an extended thermostat (up to 650°F).

Model Designations

Model Configurations Visuals

Bake Ovens

HGSO10: A single-deck oven.

HGSO11: A two-deck oven.

HGSO111: A three-deck oven.

HGSO20: A wider single-deck oven.

HGSO12: A wider two-deck oven.

HGSO22: A wider two-deck oven, appearing taller than HGSO12.

Roast Ovens

HGSO30: A single-deck roast oven.

HGSO33: A two-deck roast oven.

HGSO333: A three-deck roast oven.

Combination Bake & Roast Ovens

HGSO32: A combination oven with a roast compartment above a bake compartment.

HGSO31: A narrower combination oven with a roast compartment above a bake compartment.

HGSO311: A combination oven with two roast compartments above two bake compartments.

HGSO331: A combination oven with two roast compartments above one bake compartment.

Installation

Unpacking

Upon unpacking, check the oven for shipping damage. Save packing material and contact the carrier within 15 days if damage is found.

Verify that the gas supply and electrical service match the specifications on the machine data plate before installation.

Location

CAUTION: The equipment area must be kept free and clear of combustible substances.

Maintain minimum clearances: 6" at the sides and 6" at the rear from combustible and noncombustible construction.

Ensure the installation location allows adequate clearances for servicing and proper operation. The oven must not obstruct the flow of combustion and ventilation air. Provide adequate clearance for air openings into the combustion chamber and ensure sufficient air supply in the room for gas combustion.

Avoid fans blowing directly at the oven or open windows next to the oven that create air cross currents.

Installation Codes and Standards

In the United States:

1. State and local codes.
2. National Fuel Gas Code, ANSI-Z223.1 (latest edition), available from American Gas Assn., Inc., 1515 Wilson Blvd., Arlington, VA 22209.
3. National Electrical Code ANSI/NFPA-70 (latest edition).

In Canada:

1. Local Codes.
2. CAN/CGA-B149.1 Installation for Natural Gas Burning Appliances and Equipment (latest edition).
3. CAN/CGA-B149.2 Installation for Propane Burning Appliances and Equipment (latest edition), available from The Canadian Gas Assn., 55 Scarsdale Road, Don Mills, Ontario, Canada M3B2R3.
4. Canadian Electrical Code Part 1, CSA Standard C22.1 (latest edition).

Assembly

Legs

If mounting on legs, assemble legs to the oven. Tip oven back to install front legs with bolts, then tip forward and block up the back to install rear legs.

Remove shipping harnesses from the burner area after legs are assembled. This involves dismantling the oven deck and insulation pans, and removing 1 cotter pin and 2 wire straps.

Stacking Ovens

To stack ovens:

1. Mount the upper section on top of the lower section, ensuring flue risers are aligned.
2. Secure both ovens using 1 right and 1 left stacking collar and provided #10-24 screws (refer to Fig. 1).
3. Install the gas connection pipe (refer to Fig. 1).

Fig. 1 Description: A diagram showing two oven sections stacked vertically. It indicates 'KNOCKOUTS' for access, 'STACKING COLLARS' used to join the sections, and the 'GAS CONNECTION PIPE'.

Optional Steam Injector Nozzles

Steam injector nozzles are available for baking hard rolls, vienna bread, french bread, and hard crust breads. To install, remove the knockout(s) from the oven back and the plug(s) from the oven cavity, then insert the nozzle.

Steam pressure should be low (2½ lb. to 5 lb. per square inch). Condensation must be taken from the steam line before it enters the oven. A 1/4 HP boiler is recommended for each large (42" x 32") compartment.

Gas Connections

CAUTION: All gas supply connections and pipe joint compounds must be resistant to propane gases.

Connect gas supply using 3/4" pipe inlet connections. For double or triple sections, use the rear manifold with a 1" main gas supply. Ensure pipes are clean and free of obstructions. Use adequately sized piping with minimal elbows or tees. Consult piping charts or local gas company for sizing.

A gas shutoff valve must be installed in the gas line ahead of the oven.

Ovens are factory preset with pressure regulators: 3.7" W.C. for Natural Gas, 10" W.C. for Propane Gas. No further adjustment is typically required unless the regulator is installed in a non-horizontal position.

WARNING: PRIOR TO LIGHTING, CHECK ALL JOINTS IN THE GAS SUPPLY LINE FOR LEAKS USING SOAP AND WATER SOLUTION. DO NOT USE AN OPEN FLAME.

After checking for leaks, purge all gas piping to remove air.

Testing the Gas Supply System

If test pressures exceed 1/2 psig (3.45 kPa), disconnect the oven and its shutoff valve from the gas supply piping.

If test pressures are 1/2 psig (3.45 kPa) or less, isolate the oven by closing its manual shutoff valve.

Flue Connections

Maintain a minimum clearance of 18" from the oven flue vent termination to the filters of the hood venting system.

Do not obstruct flue gas flow. Ventilate flue gases to the outside via a system installed by qualified personnel.

Information on ventilating hoods can be found in NFPA No. 96 ("Vapor Removal from Cooking Equipment").

The oven is equipped with a flue deflector. An optional down draft diverter can be connected to a Type "B" vent.

Electrical Connections

WARNING: ELECTRICAL AND GROUNDING CONNECTIONS MUST COMPLY WITH THE NATIONAL ELECTRICAL CODE AND/OR OTHER LOCAL ELECTRICAL CODES.

WARNING: APPLIANCES WITH FLEXIBLE ELECTRIC SUPPLY CORDS HAVE A THREE-PRONG GROUNDING PLUG. THIS PLUG MUST BE CONNECTED TO A PROPERLY GROUNDED THREE-PRONG RECEPTACLE. IF THE RECEPTACLE IS NOT PROPERLY GROUNDED, CONTACT AN ELECTRICIAN. DO NOT REMOVE THE GROUNDING PRONG.

Ovens with optional inspection windows and interior lights are supplied with a cord and plug.

Operation

WARNING: THE OVEN AND ITS PARTS ARE HOT. USE CARE WHEN OPERATING, CLEANING OR SERVICING THE OVEN.

Controls (Fig. 2)

Burner Valve: Turn knob counterclockwise to open (allow gas flow), clockwise to close.

Ignition Button: Used to reset the oven pilot. Push and hold while following pilot lighting instructions.

Thermostat: Regulates heat. Ranges from 150°F (66°C) to 500°F (260°C). Optional extended thermostat goes to 650°F. Turn knob counterclockwise to increase heat, clockwise to decrease.

Fig. 2 Description: A close-up view of the oven's control panel, showing the Burner Valve, Ignition Button, and Thermostat knob.

Before First Use

Clean oven deck and lining with warm water and detergent. Rinse and dry with a soft cloth.

To remove odors from new lining, "burn-in" the oven by setting the thermostat to the highest temperature and operating for one hour.

Lighting and Shutting Down Pilot

1. Turn on main gas supply.
2. Turn burner valve ON to purge air, then turn OFF.
3. Wait 5 minutes. Turn burner valve ON and depress ignition button (see Fig. 2). Use a lit taper to ignite the oven pilot (Fig. 3). Hold button for 30 seconds, then release.
4. If pilot goes out, turn gas supply OFF and wait 5 minutes before relighting.
5. Repeat until pilot stays lit.
6. Set thermostat to desired temperature.

Lighting instructions may also be on the oven control panel.

Fig. 3 Description: A view inside the oven showing the pilot light assembly, labeled as "Oven Pilot".

Shutdown

Normal Shutdown:

1. Turn burner valve OFF.
2. Turn thermostat OFF.

Extended Shutdown:

1. Turn burner valve OFF.
2. Turn thermostat OFF.
3. Turn main gas supply OFF.

Preheating

Set thermostat to desired temperature and preheat for approximately 15 minutes before loading.

Loading Oven

1. For 2- or 4-deck sections with one control per two compartments, load both simultaneously. If loading only one compartment, use the one with the thermostat bulb. DO NOT stagger loading.
2. Load each shelf evenly, spacing pans from each other and oven walls.
3. Whenever possible, load each oven section fully. Do not add product after baking has started, as this can cause unbalanced baking.
4. Roast ovens with removable center shelves have adjustable slides. Close slides when shelf is removed; open when shelf is in position.

Cooking Hints

Minimize door opening during baking for best results.

A meat thermometer is recommended for all roasting operations.

Multi-deck ovens with a single combustion chamber and thermostat may not offer the same even heat distribution as single-deck sections.

Pan Capacities

*Compartment capacity of 12¹/₄" high roast section may be doubled when extra removable center shelf is used.

Cleaning

WARNING: TURN OVEN OFF AND UNPLUG THE ELECTRICAL CORD (IF APPLICABLE) BEFORE CLEANING.

Clean interior and exterior daily with warm water and detergent solution. Rinse and dry with a soft clean cloth.

Oven Inspection Window (Optional)

Clean with an oven cleaner compound or a cloth dampened with detergent solution. Rinse and dry with a soft clean cloth. Do not use scouring powder, as it will scratch and fog the glass.

Stainless Steel (Optional)

Clean with soap or detergent and water solution. Rinse with warm water and dry with a soft cloth. A rinsing agent can help prevent spotting.

For stubborn stains, use a paste of water and mild scouring powder, rubbing in the direction of the polish lines.

Minimize fingerprints by applying a cleaner that leaves a thin, oily or waxy film. Apply cleaner, remove excess with a dry cloth.

To remove burned-on food and grease, soak with hot soapy water. Use stainless steel wool or a sponge with a paste of scouring powder and water. Do not use ordinary steel wool, as it can rust and cause stains. Rinse and dry with a soft cloth.

Heat tint (straw-colored or slightly darkened areas) may appear on stainless steel at high temperatures. This is a slight oxidation and is not harmful. To minimize, use only necessary heat. Heat tint can be removed by vigorous scouring with stainless steel wool and scouring powder paste, rubbing in the direction of polish lines.

When scraping heavy deposits, use stainless steel, wood, plastic, or rubber tools, not ordinary steel scrapers or knives, to avoid embedding particles that can rust.

Maintenance

WARNING: THE OVEN AND ITS PARTS ARE HOT. USE CARE WHEN OPERATING, CLEANING OR SERVICING THE OVEN.

Replacing Optional Lamps

WARNING: TURN OVEN OFF AND UNPLUG ELECTRICAL CORD BEFORE REPLACING LAMPS.

Lamps are located in the top of the oven, centered at the back.

1. Remove (4) 10-24 sheet metal screws, remove glass, and unscrew (2) bulbs.
2. Install (2) new G.E. incandescent 25 watt, 120 volt bulbs.
3. Replace glass and reinstall screws.

Vent

When the oven is off and cool, annually examine the flue and clear any obstructions.

Service

Before calling for service, check the following:

• Make sure the gas supply is turned on.
• Make sure the pilot is lit.

Contact personnel qualified to install and repair gas equipment for all other maintenance problems.