O P E R A T I O N HO851G REVOLVING TRAY OVEN MODEL HO851G GAS ML-132160 24 Pan ML-132161 18 Pan ML-132258 36 Pan ML-132259 30 Pan 701 S. RIDGE AVENUE TROY, OHIO 45374-0001 937-332-3000 www.hobartcorp.com FORM 34706 Rev.
IMPORTANT FOR YOUR SAFETY THIS MANUAL HAS BEEN PREPARED FOR PERSONNEL QUALIFIED TO INSTALL GAS EQUIPMENT, WHO SHOULD PERFORM THE INITIAL FIELD START-UP AND ADJUSTMENTS OF THE EQUIPMENT COVERED BY THIS MANUAL. POST IN A PROMINENT LOCATION THE INSTRUCTIONS TO BE FOLLOWED IN THE EVENT THE SMELL OF GAS IS DETECTED. THIS INFORMATION CAN BE OBTAINED FROM THE LOCAL GAS SUPPLIER.
Table of Contents GENERAL ............................................................................................................................................. 4 INSTALLATION ..................................................................................................................................... 4 OPERATION.......................................................................................................................................... 4 General Oven Description (Fig. 1) .........
OPERATION AND CARE OF MODEL HO851G REVOLVING TRAY OVEN SAVE THESE INSTRUCTIONS GENERAL The Hobart HO851G Revolving Tray Oven has been carefully engineered and tested to deliver an excellent baking environment for a wide variety of products. It is equipped with easy-to-understand digital controls and a large, easy-to-read tray indicator display.
GENERAL OVEN DESCRIPTION (Fig. 1) Panel Stop Clip Ventilation Hood Emergency Stop Panel Gas Shut Off Valve Loading Door Loading Door Sill Service Door Interlock Service Door Digital Control Panel AUTO Button RUN Button Quick-View Panel REVERSE Button Power Switch Lower Front Panel Motor Shaft Manual-Auto Switch PL-56261 Fig. 1 DIGITAL CONTROL PANEL - Displays temperature, time and oven functions. QUICK-VIEW PANEL - Displays the status of oven systems. POWER SWITCH - Oven ON/OFF switch.
REVERSE BUTTON - Press to move trays in a downward direction. The next tray will stop when it is even with the loading door sill. RUN BUTTON - Press to start the trays moving in a continuous upward direction. AUTO BUTTON - Press to stop the trays. The next tray will stop when it is even with the loading door sill. Use the Auto button for all routine stops. SERVICE DOOR - Gives access to the interior of the oven for cleaning and servicing.
HO851G DIGITAL CONTROL PANEL WITHOUT AUTO START TRAY NUMBER window - Displays the tray that is currently at the loading door sill. OVEN TEMP. UP and DOWN arrows - Press to set the desired temperature. Temperature window - Displays the current temperature and set temperature if arrow key is pressed. TIMER STOP/START - Press to stop or start the timer. UP and DOWN arrows - Press to set the desired time on the timer. Hours and Minutes window - Displays the hours and minutes remaining on the timer.
HO851G DIGITAL CONTROL PANEL WITH AUTO START TRAY NUMBER window - Displays the tray that is currently at the loading door sill. OVEN TEMP. UP and DOWN arrows - Press to set the desired temperature. Temperature window - Displays the current temperature and set temperature if arrow key is pressed. TIMERS STOP/START - Press to stop or start the selected timer. RIGHT arrow - Press to select a timer (1 to 6). Time # window - Displays the number of the last timer viewed.
START UP PREHEAT The oven and its parts are hot. To prevent burns, use hot pads or protective mitts when loading or unloading the oven. For the best results, the oven must be preheated before baking begins. 1. Ensure all panels are in place and all personnel are clear of oven before preheating/starting oven. 2. Turn the POWER switch to the ON position.
4. Continue this same procedure until all the product has been loaded. 5. When the loading door is closed, a buzzer will sound. 6. Press RUN to silence the buzzer and start the trays rotating throughout the entire bake process. Unloading 1. Open the loading door. 2. Press the AUTO button to bring the desired tray to the loading door sill. 3. Unload the baking product from the tray. 4. Press the AUTO button again to bring the next desired tray to the loading door sill for unloading. 5.
Multiple Timers Ovens equipped with Auto Start have six individual timers that can be used for timing operations. Timers run independently and will not start or stop an operation. 1. Press the single RIGHT arrow key next to the top window in the TIMERS section to select one of six timers. The Timer Number will be displayed in the top window. 2. Enter the desired time by pressing the UP or DOWN arrows next to the Hours and Minutes window. 3. Press the STOP/START key to activate the timer.
CLOCK Displays the current time and day of the week. It is also used as a 7-day, single-event programmable timer for the Auto Start cycles. See below. Set the Current Time and Day Hour • Press and hold the UP or DOWN arrows next to the Hours and Minutes window. First, the minutes will begin to change; then after a few seconds, the minutes will stop and the hours will begin to change. • Set the current hour in the AM or PM.
Auto Start Hints • Do not use the Auto Start feature when the manual tray operation is engaged or if the ventilation motor is controlled by an external source. • The oven will not Auto Start if the loading door is open. • To turn the Auto Start feature off, press the ON/OFF key under AUTO START section. • The Auto Start feature cannot be turned off once the purge cycles have started. A zero will be displayed in the Timer number window when the purge cycles are in progress.
Changing Items in Setup Mode The number in the TIMERS section Hour and Minutes window is the Setup Number. The other windows display the setup item(s) (the settings that can be changed). Depending on what setup number is being displayed will determine what windows are lit. 1. To change the setup number displayed in the Hour and Minutes window, press the UP or DOWN arrow. The setup item(s) will be displayed in the appropriate windows. 2.
Setup Guide Items designated with a * are for ovens with Auto Start. Setup Numbers Setup Item 0 Displays program version number in Temperature window and oven type number in Hour and Minutes window. 1 The oven can be set to display the temperature in Celsius or Fahrenheit. 2 This is the minimum temperature that the oven can be set. 3 This is the maximum temperature that the oven can be set. 4 Select military (24 hour) or standard time.
CLEANING The oven and its parts are hot. Use care when operating, servicing or cleaning the rack oven. • Allow the oven to cool. • Clean the outside of the oven daily with a clean, damp cloth. MAINTENANCE The oven and its parts are hot. Use care when operating, servicing or cleaning the oven. Disconnect the electrical power to the machine and follow lockout / tagout procedures. INSPECTING THE OVEN Every Other Week 1. Check the stop panel for proper operation. 2. Inspect the area around the oven.
Recommended Lubrication Dow Corning C-40 High Temperature Chain Lubricant • Hobart Part No. 01-10G108-00001 (4 oz) • Hobart Part No. 01-10G108-00002 (1 qt.) Lubrication Frequency Based on Usage Lubrication Frequency Duty Cycle Monthly Every 3 Months Light Duty 56 hours per week (8 hours per day, 7 days per week) X Medium Duty 57 to 84 hours per week (12 hours per day, 7 days per week) X X Heavy Duty Oven 84 hours per week Lubrication Procedure 1. Allow oven to cool below 250°F (121°C).
TROUBLESHOOTING ALL OVENS GAS 5 GAS VALVE POWERED 6 FLAME FAILURE 7 LOADING DOOR CLOSED 8 PURGE MOTOR POWERED 9 PURGE POSITION VERIFIED 10 PURGING MOTOR 1 SERVICE DOOR CLOSED 2 HOOD AIRFLOW VERIFIED 3 TEMP. LIMIT CLOSED 4 THERMOSTAT OUTPUT POWER PURGE The Quick-View oven status display (Fig. 2) on the control panel shows the status for the various systems of the oven. The Quick-View Status Lights (Fig. 3) explains what each light means. Some problems can be corrected by the user.
Quick View Status Lights Light Number Normal Operation Problem Probable Cause Corrective Action 1 Light is on. Light is off. Service door is open. Close service door. 2 Light is on. Light is off. Inadequate hood airflow. Call service. 3 Light is on. Light is off. Temperature limit of oven has been exceeded. Cool oven down. 4 Light is on when calling for heat. Light is off when Control PC board is the oven is calling not sending power to for heat. ignition module. Call service.
EMERGENCY TRAY OPERATION The emergency tray operation procedures are used only if the trays will not operate by normal pushbutton operation and tray movement is required to unload the product. Electrical Tray Operation If there is a component or electrical part failure in Auto Mode, this procedure allows the trays to be operated with the power on. 1. Turn POWER SWITCH to the OFF position. 2. Lift out the two Lower front panels from the oven (Fig. 1). 3.