MCO Service Manual Robertshaw
Contents
1. 23 CONVECTION OVEN MOTOR ASSEMBLY icono 24 MAIN BURNER PILOT BURNER amp DOOR MICRO SWITCH LOCATION 24 SECTION 4 COMMON WIRE DIAGRAMS nusnennsnenennonunnonunennunnnnanunnnnunnnanennnunnsnanennnunnsnunennnnnranunenn 26 SECTION 1 SPECIFICATION amp DIMENSIONS GAS CONVECTION OVEN GAS SPECIFICATIONS MAIN PILOT GAS BURNER PILOT ORIFICE PRES W C ORIFICE ORIFICE NAT PRO MCO 40 000 lea 55 020 012 0781 MCO 60 000 lea 55 3 020 012 0781 MCO 80 000 55 4 020 012 0781 Gas pressure measured at burner manifold Gas pressure measured at redundant gas valve pressure tap All models single deck ovens amperage rating is 6 2 each oven Manifold size is N P T National Pipe Thread NOTE Two speed motor 1140 and 1725 R P M 60 Hz clock wise motor rotation looking into oven cavity NOTE Each deck supplied with a 6 ft power supply cord for 120 volt units DIMENSIONS amp SPECIFICATIONS 1 2N P T 38mm 7 13mm 7 3 4 1 GASINLET H l Tee IT UEM 1 4 716 mm 2 38 5 3 4N PT l 1 60mm x 127mm LT 19mm l 43 aces T 1 ve 54 916 1099mm DEEP al 1386mm 39 1 4STD t 1 997mm STD 32 38 1 1 I 813mm 965mm 1 I 35 916 903mm 1 a az jy r 1 N l i ur NS E 451mm Su mm 38 Pd psm2. AA 1 ias Lor N SN DE y Single Deck Front View Top View Double Deck Front View Model D w D Lb KG CuFt 28 711mm 38 965mm INPUT CHART Natural or Propane Gas ELECTRICAL CHARACTERISTICS Model KW sru equ 120v Phase zaovit Phase MCO GS 10 60 000 One 34 NPT One 6 2 Amps One 3 1 Amps HP MCO GS 20 120 000 One Q1 NPT Two 6 2 Amps Two 9 3 1 Amps HP MCO GD 10 60 000 One 34 NPT One 6 2 Amps One 3 1 Amps SECTION 2 OVERVIEW OPERATIONAL SEQUENCES Understanding the sequence of operation is necessary in properly trouble shooting this appliance In this section the sequence of operation will be covered first as well as calibration and operation of components and basic trouble shooting techniques for that specific model Follow each sequence carefully and get to understand its operation before moving on to trouble shooting MANUAL CONTROLS Sequence of Operation Starting with the oven doors in closed position HIGH POWER 1 Turn the Mode Switch to the Cook position This sends line voltage to the timer And with the doors closed line voltage is sent via the door switch to the thermostat and the Hi Lo Fan switch 2 Select Hi or Lo speed the motor will now be operational 3 Rotate the temperature dial to desired temperature The thermostat will now call for heat sending line voltage to the 24 volt tr
3. NOTE If the ground circuit path is incomplete the S86H system control will allow one trial for ignition before going into safety lockout Electrical grounding connections at the pilot burner ignitor sensor and S86 must be clean and tight If lead wire is damaged or deteriorated use only No 14 of 18 gauge moisture resistant thermoplastic insulated wire with 105 C 221 F minimum rating as replacement Excessive temperature at the ceramic flame rod insulator can also permit electrical leakage to ground Examine the flame rod and mounting bracket and correct if bent out of position Replace ignitor sensor of insulator is cracked CHECK SPARK IGNITION CIRCUIT The electronic module and step up transformer in the S86 provides spark ignition at 15 000 Volts open circuit This circuit can be checked at the S86 module as follows 1 Turn off the manual gas cock to prevent the flow of gas 2 Disconnect the ignition cable at the S86 stud terminal to isolate the circuit from the pilot burner ignitor sensor and prepare a short jumper lead using heavily insulated wire such as ignition cable 3 Energize the S86 Touch one end of the jumper firmly to the S86 ground terminal GND Do not disconnect the existing ground lead Move the free end slowly toward the stud terminal to establish a spark and then pull the lead wire slowly away from the stud Note the length of the gap at which arcing stops CAUTION Do not touch either stripped end of j
4. Set the cook temp to X40 Depress amp hold the Start button for five seconds Rotate either dial to display 50 or 60 Hz CHAIN PROGRAMMING de Press Pgm Mode on off Select Pgm 1 5 Enter Event 1 parameters time temp fan speed etc Press Event key to chain 2 event Enter Event 2 parameters Continue procedure up to six events FIRST STAGE TRIAL FOR PILOT IGNITION Depress the Actual Temp button to lock in Depress the Actual Temp button to lock in Depress the Actual Temp button to lock in Depress the Cancel button to lock in Press Pgm Mode on off to exit program mode On every call for heat system start the S86 performs an internal safe start check shows that a flame simulating condition is present During a normal start the S86 opens the pilot valve in the gas control This allows gas to flow to the pilot burner Simultaneously the electronic spark generator in the S86 produces a 15 000 volt spark pulse output 12 This voltage produces a spark at the pilot burner ignitor sensor rod igniting the gas flowing around the electrode If the pilot flame is not detected during the trial for pilot ignition the S86H contains a safety lockout timer 90 Seconds to limit the trial for pilot ignition period SECOND STAGE MAIN BURNER OPERATION When the pilot flame is established a flame rectification circuit is completed to the burner ground The S86 flame sensing circuit de
5. END Valves close pilot and main burners are off SERVICE PRELIMINARY CHECK The following visual checks should be made before trouble shooting and after installation or maintenance 13 Check power to appliance and S86 Manual shutoff cocks in gas line to appliance must be open Make certain all wiring connections are clean and tight First de energize the system and wait at least one 1 minute This resets the module allowing a return to start condition Then energize the system 5 Review the S86 system normal sequence of operation SYSTEM TROUBLE SHOOTING Start the system by setting the thermostat or controller above required temperature Observe system response Establish type of malfunction or deviation from normal operation Use the S86 Intermittent Pilot System Trouble Shooting Table to check for normal system operation Use table by following instruction questions in box If the condition is true or okay answer yes go down to next box underneath If the condition is not true or not okay answer no go right to the next box alongside Continue checking and answering conditions in each box encountered until a problem and or the repair is explained After any maintenance or repair the trouble shooting sequence should be repeated until the trouble shooting procedure ends with a normal system operation START NOTE Before troubleshooting familiarize yourself with he startup and checkout procedure TURN GAS SUPPLY
6. OFF TURN THERMOSTAT TE CONTROLLER TO CALL Check line voltage power low voltage transformer limit controller thermostat FOR HEAT controller and wiring POWER TO MODULE 24v NOMINAL Pull ignition lead and check spark at module SPARK ACROSS IGNITOR SENSOR GAP Spark okay On models with vent damper plug make sure vent damper had not been installed then remove Replace vent damper if necessary On other models replace module Check ignition cable ground wiring ceramic insulator and gap and correct Check boot of the ignition cable for signs of melting or buckling Take protective action to shield cable and boot from excessive temperature Check that all manual gas valves are open supply tubing and pressure are good TURN GAS SUPPLY ON and pilot burner orifice is not blocked Check electrical connections between module and pilot operator on gas control Check for 24 Vac across PV MV PV terminals on module If voltage is okay PILOT BURNER LIGHTS replace gas control if not replace module Y NOTE If S8600B H S8610B H goes into lockout reset system For S8600M wait 6 minutes nominal for retry or reset system SPARK STOPS WHEN Check continuity of ignition cable to ground wire PILOT IS LIT no Clean flame Check electrical connection between flame rod and module ES Check for cracked ceramic flame rod insulator ES E Check that pilot flame covers rod and is stead
7. OVEN TEMPERATURE SENSOR The chart below will provide the Ohms at various temperatures This will enable you to determine if the temperature probe is operable The chart is in Degrees Fahrenheit How to use chart for 350 read down to 300 then across to 50 answer is 1654Ohms of resistance TEMP 0 10 20 30 40 50 60 70 80 90 0 932 953 974 995 1016 1038 1059 1080 1101 1122 100 1143 1163 1184 1205 1226 1247 1267 1288 1309 1329 200 1350 1370 1391 1411 1432 1452 1472 1493 1513 1533 300 1553 1574 1594 1614 1634 1654 1674 1694 1714 1733 500 1949 1969 1988 2008 2027 2046 2065 2085 2104 2123 ROBERTSHAW COM6000 CONTROLLER The controller needs voltage to operate and is capable of operating on three 3 different line voltages 115 Vac 208 Vac 240 Vac On the back of the Robertshaw COM6000 there are several 14 male spade terminal or pin connections The below is a drawing of the rear of a Robertshaw COM6000 Controller along with a definition of each of the pin connections 24QV 208V 120V NEUTRAL AUX lt GROUND BAKE lt D gt gt PROBE DOOR REAR VIEW FRONT VIEW OPERATION OF THE TEMPERATURE FUNCTION When the controller is powered up the LED will be illuminated To enter a cook temperature rotate the right dial The digits will go up as you rotate the dial to
8. Table of Contents to locate the topic and function that you are attempting to trouble shoot Table of Contents SECTION 1 SPECIFICATION amp DIMENSIONS 2 22 24222222222200020000000n0nnnuanznnnunanunnnunnnnnnunnnnnnun ann 4 GAS CONVECTION OVEN GAS SPECIFICATIONS ssssscssssssssssssssesssssssssssssssscecessesscssessscesessenssssscessesesssscsesesessesesssscsssecesessesesecessese 4 DIMENSIONS amp SPECIFICATIONS scsscssssssssssssssssssssscsssssssssasssssenencasscecsesssnsssasacsscseacasesosscssesenensaeascseasassusosacaessenencaascecseassecesasas 4 SECTION 3 OVERVIEW OF OPERATIONAL SEQUENCES 2 22 222 2n2an2nan0a2n0n0nunnnnnunnznnnunnnnnn 5 MANUAL CONTROLES n 5 Sequence of Operation cccccccccccsssssesssssscsesesssescsesessesesessseceesesssssscssseseussscsesecassesesassesssesecaesesssseacsesescauseseseecaesesasaescseseseuseaesaescseaeeesaeaeseas 5 Manual Ladder Diagram oh e e RERO Te rase tien debet ELLI 3 CALIBRATION OF THERMOSTAT ELECTRONIC CONTROLS 8 Sequence of Operation With the Oven Doors Closed tenente netten tenente tenen tenete tenen tenee tenente 8 Elect nic Ladder Wire Diagram edo tette esse ee oben PORTUS 8 ELECTRON
9. no effect on the bake relay OPERATION OF THE HOLD FUNCTION When the controller has a HOLD temperature programmed the controller operates a little differently As noted earlier set cook temperature and time When the timer counts down to 00 00 the alarm will sound for five 5 seconds and the word HOLD will now be displayed in the time side of the LED display The AUX relay will also be deactivated at this time and stop the oven fan At the same time the cook temperature will change to the new hold temperature that was preprogrammed in the controller This new temperature will now blink indicating that a new set temperature must be reached Once this new set temperature is reached the digit will go constant After reaching the new set temperature the AUX relay oven fan and Bake relay heat will cycle together To cancel depress the Cancel Timer key on the control This controller will remain in this HOLD program until removed see User Preference Programming in the following pages OPERATION OF THE PULSE FUNCTION 10 When Pulse Program has been entered in the controller the AUX relay will open for 30 seconds and close for 30 seconds The 30 seconds open amp closed is a factory preset time and cannot be altered in the field The controller will remain in this Pulse Program until removed see User Preference Programming in the following pages USER PREFERENCE OFFSET FOR THE ELECTRONIC CO
10. the pilot flame and electrical connections as described above Also replace the ignitor sensor if the ceramic insulator is cracked EXAMPLES OF UNSATISFACTORY PILOT FLAMES APPEARANCE CAUSE SMALL BLUE FLAME Check for lack of gas from Clogged orifice filter Clogged pilot filter Low gas supply pressure Pilot adjustment at minimum LAZY YELLOW FLAME Check for lack of air from Large orifice Dirty lint screen if used Dirty primary air opening if there is one Pilot adjustment at minimum Check for Excessive draft at pilot locations Recirculating products of combustion 16 NOISY LIFTING BLOWING FLAME HARD SHARP FLAME Check for High gas pressure This flame is characteristic of manufactured gas Check for High gas pressure Orifice too small SECTION 3 ACCESS OF FUNCTIONAL COMPONENTS This section will give you the best way to access component for replacement COMPONENT LOCATIONS 17 Top Front Center Door Chain Door Catch Right Front Control Panel 24v Transformer Ignition module Redundant gas valve Lower Front Door Micro Switch Data Plate Burner Package Inside Oven Oven Convection Motor Oven Interior Lights Single Deck Front View Door Gasket Replacement Open oven doors Locate stainless steel door gasket mounted to oven front frame Remove the 10 Phillips sheet metal screw that attach the retainer to the oven s front frame Re
11. to the 24 Volt Transformer The bake relay completes the circuit from the 24 volt transformer to the ignition module and ignition occurs heating the oven Below is a simplified power diagram 24 Volt Motor Transformer Centrifugal Switch 24 V Thermostat Ign Module Hi Speed Door Sw Motor Relay Lo Speed Neutral Mode Sw COM6000 Light Sw ELECTRONIC CONTROL FAILURE CODES The GARLAND digital control has a self diagnostic program If a problem occurs within the digital controller you may see one of the F codes Below is a listing of the F codes with explanations F1 F2 F3 F4 F5 F6 F7 Relay output is enabled when not cooking If this failure code appears in the display the cook relay may be on even if the control is not cooking The control should be replaced Over temperature alarm If this failure code appears in the display the control is sensing an oven temperature 50 or more above the maximum set temperature 500 This failure may be caused by a faulty sensor Check the sensor connection for loose wires Replace the sensor and check for proper operation If failure continues replace the control Open sensor circuit If this failure appears in the display the control is sensing an open circuit at the sensor input This failure is most often caused by a poor connection or broken sensor Check sensor connection and leads for bro
12. 4 10 sheet metal screws that secure air baffle and remove air baffle Remove six hex nut 1 4 20x7 16 2A and lock washers 4A from motor mounting studs Place a piece of cardboard on oven floor to protect from scratching or chipping Pull entire motor assembly 1A away from rear oven wall into oven cavity and place on cardboard Disconnect wiring be sure to note wire locations To reinstall reverse above procedure 2 di l l 9 l Y 2 l l Y 1 l N 1 Se 1 l l A OR gt 7 2 3 AS N Mod oc ES o 3 7 PX 2 Dich AT See x D 1 N ER ZO CO QR M REES bL XR CY A Un 7 et US x 2 Sy F 6 T 2 SEN di 4 HIN M 1 H E AN wf XE S S 72 IDO 4 Fb DEA TO Y GS ge y n M FILE JIT00024 Dd ir pios ne LT em Convection Oven Motor Assembly 6 a PIX en FILE NAME JIT00012 1 Assemble motor mount plate 2 insulation 2 motor mount plate inner together by fastening four flat head m s 1 4 20x2 7 25 into the four holes noted on the above drawings 2 Secure each flat head m s 1 4 20x2 zt with a flat washer 2 and three hex nuts 1 4 20 es Attach motor mounting plate to motor 25 Insert the four flat head m s 1 4 20x2 2 lt through the mounting tabs on motor 2 as shown Secure
13. GARLAND IR A WELBILT COMPANY BUILT TO LEAD BUILT TO LAST SERVICE MANUAL THE MASTER GAS CONVECTION OVENS Models covered in this manual are MCO GS 10M MASTER CONVECTION Oven GAS STANDARD DEPTH 10 SINGLE DECK Manual CONTROL MCO GS 10E MASTER CONVECTION OVEN GAS STANDARD DEPTH 10 Single DECK ELECTRONIC CONTROL MCO GD 10M MASTER CONVECTION Oven GAS DEEP DEPTH 10 SINGLE DECK Manual CONTROL MCO GD 10E MASTER CONVECTION Oven GAS DEEP DEPTH 10 SINGLE DECK ELECTRONIC CONTROL GARLAND Commercial Industries Inc 185 East South Street Freeland Pennsylvania 18224 DIRECT ON SITE SERVICE 1 800 451 1165 2 GENERAL INFORMATION 1 800 424 2411 FORM GCI MCOVN PRINTED IN THE U S A This service manual is designed to answer questions related to model operational requirements troubleshooting and disassembly assembly procedures It contains electronic ignition operation trouble shooting and electronic control operations that include diagnostic codes ladder diagrams wire diagrams and troubleshooting It also includes BTU ratings orifice size and gas pressure technical data for each model For example if you need to know information on manual controls manual controls controls the oven with hydraulic thermostat electric mechanical timer refer to SECTION 2 OVERVIEW OF OPERATIONAL SEQUENCES Sequence of Operation This book is broken down into sections each section will list the applicable topics Use the
14. IC CONTROL 9 CHART FOR INTERNAL OVEN TEMPERATURE SENSOR ussssssnsnsnsnsesensnsenenenenensensnsnsnsensnenesnenenenensensnsnsnsunsnsnsnssnenenenssssnsnensensnsnsnse 9 ROBERTSHAW COM6000 CONTROLLER uuussensnesnenennenunnenunennunnnnanunennunnnnanunnnnunnnnanennnnunnenanennennnrann 10 USER PREFERENCE OFFSET FOR THE ELECTRONIC CONTROLLERS ussssssnsnsnsessnensnsenenenensensnsnensunsnsnenssnensnenssssnsnensunenenensnnen 11 COM6000 UPO MODE COM6700 UPO MODE SERVICE noc 13 PRELIMINARY 2 rre re P RR RE A LS 13 DOOR GASKET REPLACEMENT escisiones 18 TO REMOVE DOORS FROM THE OVEN ic rnnthn rue da uie ach ran onn han namen aha dS 19 INSTALLATION OF OVEN DOO PS cune o hh nn mann o Gs ag 20 INSTALLING AND ADJUSTMENT OF THE DOOR CHAIN eres ennt tntn nnnm ns 20 DISASSEMBLY OF THE LEFT DOOR rca na RE Cu 20 DISASSEMBLY OF THE RIGHT DOOR W O WINDONWY cernerent nntn nnns 21 TO REPLACE OR ADJUST DOOR LATCH 23 TO REPLCAE CONVECTION OVEN MOTOR
15. NTROLLERS The User Preference Offset is designed to enable the user to adjust the controlling temperature There are two different styles of controllers used by GARLAND at the present time They are the Robertshaw COM6000 and COM6700 Series To determine which of the controllers you are working on look at the back of the controller and you will see a sticker with a printed number like PN 100 289 03 below this number is the controller style number For example COMA 6704 GL This indicates that controller is in the COM6700 Series Or if the number was COM 6000 GA it would indicate that it is a COM 6000 COM6000 UPO MODE Set the time digits to 00 00 Depress the Set the temperature digits to X10 Cancel button to Depress both the Start and Cancel buttons for five seconds lock in Set the time digits to 00 00 Depress the Set the temperature digits to X20 Cancel button to Depress both the Start and Cancel buttons for five seconds lock in Rotate either dial to display FFF or CCC in the temperature display Set the time digits to 00 00 Depress the Set the cook temp to X30 Cancel button to Depress both the Start and Cancel buttons for five seconds lock in Rotate either dial to display HR or MN CHANGE THE HERTZ Set the time digits to 00 00 Depress the Set the cook temp to X40 Cancel button to Depress both the Start and Cancel buttons for five seconds lock in Rotate either dial to display 50
16. andle amp Carefully pry off the door panel 25 from the door window bezel zs 4 Remove 2 hex head m s 1 4 20 x Y2 from the door liner 25 that attach hold down straps 25 to the door liner 25 5 Lift out the door frame 2 6 Carefully pry off the door window for door liner 2 7 To remove door catch remove 2 pan head Phillips screws 8 Toreassemble reverse above procedure NOTE There is a seam one side of the bezel that is part of the door window 27 reinstall working from the opposite side that the seam is on and work around the window towards that seam Disassembly of the Right Door w o window 21 NOTICE DEPENDENT RIGHT HAND DOOR SHOWN un E E Sa 1 1 i i 1 I 4 1 Once the door has been removed from the oven refer to instructions on page 19 remove 9 truss head s m s 10 x 1 2 e from the top bottom and left side as shown from the door panel 25 2 Pry the door liner 25 apart from the door panel 25 This will expose the door frame 25 To reassemble reverse above procedure 22 To Replace or Adjust Door Latch Mechanism N Open oven doors Remove 2 pan head Phillips screws Lift door latch mechanism 25 up and out of door assembly To adjust latch mechanism 25 loosen lock nut 2 8 and adjust by tightening or loosening adjustment nut To Replace Convection Oven Motor Assembly Drawing Below Open doors and remove all oven racks Remove
17. ansformer With the motor operating the centrifugal switch is closed completing the neutral circuit to the transformer 4 The 24v transformer now sends 24 volts to the ignition module 5 The ignition sequence starts and oven temperature begins to rise See Ignition Sequence later in this manual Below is a simplified power diagram Hi Lo Sw Hi Speed Door Sw Mode Sw N IH Y Thermostat Neutral 24 Volt Motor Transformer Centrif Sw Light Sw Ign Module CALIBRATION THERMOSTAT 4 INSTRUMENTATION A thermocouple type test instrument is preferred for measuring oven temperatures accurately Mercury thermometers are acceptable providing they can be proven accurate Regardless of the type instrument used it is most desirable to double check it just before making an oven temperature check This can be done simply and quickly by placing the thermocouple tip or immersing the entire mercury thermometer in boiling water Note Mercury oven thermometers should be the total immersion type The resulting reading should be within several degrees of 212 depending on the altitude Generally a mercury thermometer can drop in excess of 25 when the doors are opened to check oven temperature This condition makes it extremely difficult to get a true temperature reading Almost all ranges today have oven burners which cycle on and off The high and low points of the resulting temperature
18. ken wires of loose connections Replace sensor and check for proper operation If failure continues replace control Shorted sensor circuit If this failure appears in the display the control is sensing a short circuit at the sensor input This failure is most often caused by loose wires at the connection of shorted sensor leads Check sensor connection and leads for loose wires Replace sensor and check for proper operation If failure continues replace control Relay outputs not enabled when cooking If this failure appears in the display the control cannot turn the relays on even when cooking The control should be replaced No 60 Hz input The control does not sense the input power This failure mode is most often the result of a failed component in the control However this failure may also be the result of a very noisy power line Look for any large electrical noise producing machinery such as mixers compressors dishwashers etc If possible turn these machines off Reapply power to the oven If the failure repeats replace the control If the failure does not repeat an electronic control may not work in this application because of noise You must isolate the supply circuit The control has detected that calculated EEPROM check sum is not the same as the expected check sum retrieved from the EEPROM When the control detects this error code it will disable outputs before the alarm sounds RESISTANCE vs TEMPERATURE CHART FOR INTERNAL
19. move stainless steel door gasket Replace stainless steel door gasket and to reverse above procedure to re install Se ee 18 ES E FILE NAME Y s JIT03418 E To Remove Doors from the Oven Remove top front cap veneer 25 Remove door chain assembly NOTE The A model does not come equipped with door chain Remove flat head metal screw 1 4 20x1 2 2 from bearing retainer Push the door toward hinge and lift up NOTE Bottom bearing retainer will stay in place Remove the right door in the same manner 19 i i i i i i i i i i i i i E FILE NAME JITO3459 To Reinstall Doors onto Convection Oven 1 Reverse procedure above 2 Close doors 3 Reinstall the door chain 2 Links Installing and Adjusting Door Chain 4 Make sure two links are between sprocket and door rod and there should be 8 regular links plus one master link on the forward side of each chain 5 Tighten up turn buckles the right door should close approximately 1 2 before the left door Turnbuckles x do 6 Secure the turnbuckles by tightening lock a nuts Locking Nuts wer Door Stop Bolt Disassembly of the Left Door 20 To disassemble left door 1 Once the door has been removed from the oven refer to instructions on the previous page remove the 12 truss head 10 x Phillips screws 2 2 Remove 2 allen head cap screws from the door h
20. or 60 Hz TO SET HOLD TEMPERATURE Set the time digits to 00 00 Depress the Set the cook temp to X50 Cancel button to Depress both the Start and Cancel buttons for five seconds lock in The word hold will now be displayed in the time display Rotate either dial to set hold temperature TO SET OVEN INTO PULSE MODE 11 Set the time digits to 00 00 and temperature digits to 000 Depress both the Start and Cancel buttons Rotate either dial to display con for continuous operation or for cycling fan on amp off Depress the Cancel button to lock in COM6700 UPO MODE pty Et UPO User Preference Offset Used by the user to adjust the controlling temperature 50 in 1 increments Set the time digits to 00 00 E Set the temperature digits to X10 Depress amp hold the Start button for five seconds UPO amp Current UPO will be displayed Turn TEMP or TIME dial to adjust TO CHANGE FAHRENHEIT TO CELSIUS and vise versa Set the time digits to 00 00 Set the temperature digits to X20 Depress amp hold the Start button for five seconds Rotate either dial display or in the temperature display TIMER RESOLUTION CHANGING Set the time digits to 00 00 Set the cook temp to X30 Depress amp hold the Start button for five seconds Rotate either dial to display HR or MN CHANGE THE HERTZ Set the time digits to 00 00
21. oven has been allowed to preheat record the temperature at which the burners cycle ON and OFF Average the two readings that average should be 20 of the set point temperature Example Thermostat set point at 300 first cycle Off at 325 Cycle back ON at 291 The average of 325 and 291 is 308 This thermostat is with the 20 tolerance If the thermostat is cycling beyond the 20 tolerance and the appliance is under warranty recalibrate the thermostat or if not under warranty consult owner for proper action If the thermostat is out of calibration more than fifty 50 it will not likely hold an attempt of recalibration we suggest that the thermostat be replaced 4 Increase l l T 4 e a Decrease 1 4 Turrr CALIBRATION NOTES ELECTRONIC CONTROLS Sequence of Operation With the Oven Doors Closed 1 Line Voltage is supplied to the Mode Switch Door Switch and the Momentary Light Switch Set Mode Switch to COOK and close the oven doors Line Voltage is sent from Mode Switch to power up the Controller and to the AUX relay on the controller With the oven doors closed Line Voltage is sent to the 24 volt transformer Set desired temperature The controller s relays now close The AUX relay sends Line Voltage to the motor relay coil closing the circuit to the Hi Lo Fan Switch The motor now operational causes the centrifugal switch to close and send the Neutral Voltage
22. swing differential in the oven must be measured and averaged to determine the true operating temperature A thermocouple type test instrument is best suited to measure these temperature changes quickly and accurately and without opening the oven door With an accurate thermocouple test instrument or mercury thermometer it is still difficult to measure these changing oven temperatures and then average them correctly This is why we recommend that the thermocouple tip or the bulb of the thermometer be weighted Weighting adding mass to the test instrument compensates for oven temperature changes by making the test instrument less sensitive to these constant changes in temperature Note How this weighting can be done is discussed later Measuring these changing high and low temperatures points in an oven is possible with either type of test device without weighting but is subject to possible inaccuracies This is most true at low temperature setting because in this area the function of time becomes a factor The simple averaging of temperatures then may not produce the true operating temperature Weighting provides the compensation for both time and temperature that is necessary We produced next page test curves showing actual results in the low temperature area showing the difference in results when using an unweighted and a weighted thermocouple or thermometer Tests were made with the same control same oven and dial at 170 mark no
23. t moved Chart No 1 Chart No 2 200 LA JA TI TIA ANTTIA NTIN NI ALITI ER O RAN 16 POO 120 E UN ee 100 Unweighted Thermocouple dial setting 170 F Weighted Thermocouple Dial Setting 170F From the above it can be seen that an error of 15 is possible Chart 1 unweighted thermocouple indicates an erroneous average oven temperature of 185 Chart 2 weighted thermocouple indicates the average or true temperature to be 170 WEIGHTING A thermocouple can be weighted by clamping the tip between two one inch squares of 1 16 thick aluminum The thermocouple can also be weighted just as successfully by using a letter size sheet of aluminum foil Fold the foil five times doubling the thickness with each fold After the fifth fold place the thermocouple tip in the center of the aluminum piece and fold once more Finally fold in the sides so that the foil clings to the thermocouple tip A mercury thermometer can be weighted in much the same way by wrapping several layers of aluminum foil around the bulb end thus creating the necessary mass This procedure is a must if you open an oven door to check temperature THERMOSTAT OPERATION It is normal for a hydraulic thermostat cycling with a temperature swing of 45 to 50 When checking calibration first allow the thermostat to cycle a minimum of four 4 times second place your temperature sensor in the geometric center of the empty oven Once the
24. tects the flame current and shuts the spark generator off At the same time the second operator main gas valve is opened in the gas control allowing gas flow to the main burners The pilot flame ignites the main burner conventionally SAFETY LOCKOUT TIME The safety lockout timer circuit starts timing the moment the trial for pilot ignition starts When the timing period runs out the trial for ignition ends and the control module goes into lockout Before another attempt to start can be made the S86 must be reset Reset by adjusting the thermostat or controller or to its OFF position An alternate method is to shut the system power OFF If normal ignition does not occur use the trouble shooting table to determine the problem START THERMOSTAT CONTROLLER CALLS FOR STAGE 1 E TRIAL FOR et abs ple open Gp IGNITION PEE 7 PILOT BURNER OPERATION Pilot burner lights OR Pilot burner does not light Module senses flame After 90 second system current locks out must be manually reset Shutoff lockout timing is stamped on module STAGE2 FLAME CURRENT SENSED MAIN BURNER Do ark generator off OPERATION 9 POWER INTERRUPTION Second valve operation main opens System shuts off restarts when power is restored BURNER OPERATION Module monitors pilot flame current PILOT FLAME FAILURE Main valve closed Module starts trial for ignition THERMOSTAT CONTROLLER SATISFIED
25. the right and decrease if rotated to the left The controller determines if the oven is at set temperature by the RTD sensing probe If the controller senses that the oven is below the displayed set temperature the controller activates the bake relay calling for heat At the same time the temperature digits begin to blink indicating that the controller is calling for heat Once the controllers set temperature is satisfied the temperature digits will stop flashing and remain constant and deactivating the bake relay NOTE The temperature digits will remain constant unless the set temperature is altered If altered the digits will again blink until the new set temperature is reached The controller will hold a tolerance of 5 To access the actual oven temperature depress the start key for three 3 seconds and the temperature will now display the actual oven temperature OPERATION OF THE TIMER FUNCTION To enter a desired cook time rotate the left time dial The digits will display in the first hour minutes amp seconds Above the first hour the timer will display in hours amp minutes The diplay will continue to blink until the START TIMER key is depressed The resolution of the timer can be altered to display only hours and minutes if desired see User Preference Programming in the following pages At the end of the timed period an alarm will sound until operator depresses the Cancel Timer key The timer in standard mode has
26. umper or stud terminal This is a very high voltage circuit and electrical shock can result Perform the test immediately upon energizing the system before the S86H goes into safety lockout and interrupts the spark circuit 4 arc length of 1 8 3 2 mm or more indicates satisfactory voltage output Replace the 586 if no arc can be established or the maximum gap is less than 1 8 3 2 mm and the fuse and power to the S86 input terminal was okay CONTROL MODULE FLAME SENSOR CIRCUIT 15 The control module provides AC power to the ignitor sensor which the pilot burner flame rectifies to direct current If the flame signal back to the control module is not at least 1 0 A DC the system will lockout The output of the flame sensing circuit cannot be checked directly so check the flame sensing circuit indirectly by checking the flame sensing current from the ignitor sensor to the control module as follows 1 Connect a meter DC micrometer scale in series with the flame signal ground wire Burner Ground Terminal Disconnect the ground wire at the control module Connect the red positive lead of the meter to the free end of the ground wire Connect the black negative meter lead to the quick connect ground terminal on the control module 2 Restart the system and read the meter The flame sensor current must be at least 1 0 A and the reading must be steady If the reading is below the value designated or the reading is unsteady check
27. with two hex nuts 1 4 20 25 4 Insert shaft of motor 2 through the hub of the blower wheel Space the blower wheel 25 14 away from the inner motor mounting plate 2 5 Secure the blower wheel 2 to the shaft of the motor 25 by tightening the two set screws 25 on the blower wheel hub Use a torque wrench and tighten to 180 inch pounds for proper securing For warranty replacement we require that you use the motor assembly Order motor assembly part CK1003090 2 Speed 115 Vac or CK1003091 2 Speed 208 240 Vac Export or Special CK1003092 1 Speed 115 208 240 Vac Main Burner Pilot Burner Removal amp Door Micro Switch Location 24 To access the Burners Pilot or Door Switch remove the lower combustion chamber not show This exposes these components also you will note that the rating or data plate is on the inside of the combustion shroud For ovens that are 80 000 B T U s there are four burners 60 000 B T U s there are three burners as shown in the above illustration and 40 000 B T U s there are two burners On 40 000 B T U models the pilot is located where the left or first burner usually is The two main burners are located in the center of the burner manifold By centering the burners it provides more uniform heating of the oven cavity 25 SECTION 4 COMMON WiRE DIAGRAMS 26 27 28 29 30
28. y and blue Adjust pilot flame X If problem persists replace module MAIN BURNER LIGHTS Check for 24 Vac across MV MV PV terminals If no voltage replace module NO p Check electrical connections between module and gas control If okay replace gas control or gas control operator NOTE If S8600B H S8610B goes into lockout reset system For S8600M wait 6 minutes nominal for retry or reset system Check continuity of ignition cable and ground wire NOTE If ground is poor or erratic shutdowns may occur occasionally even though operation is normal at the time of checkout Check that pilot flame covers flame rod and is steady and blue If checks are okay replace module CALL FOR HEAT ENDS NO SYSTEM SHUTS OFF Check for proper thermostat controller operation Remove MV lead at module if valve closes recheck temperature controller and YES hod wiring if not replace gas control TROUBLESHOOTING ENDS Repeat procedure until troublefree operation is obtained S86 CHECKOUT AND TROUBLE SHOOTING CHECK GROUNDING A common ground is required for the pilot burner the ignitor sensor the GND terminal of the S86 and the main burner The main burner generally serves as the common ground If the ground is poor or erratic safety shutdowns may occur occasionally even though operation is normal at the time of the checkout Therefore if nuisance shutdowns have been reported be sure to check the grounding
Download Pdf Manuals
Related Search