Blodgett MT3855G Service Manual

Download

MT3855

CONVEYOR OVEN

SERVICE AND REPAIR MANUAL

BLODGETT OVEN COMPANY

www.blodgettcorp.com

50 Lakeside Avenue, Box 586, Burlington, Vermont 05402 USA Telephone (802) 658Ć6600 Fax: (802)864Ć0183

PN M8402 Rev B (6/01)

Duplication of the information in this manual is prohibited without the consent of the Blodgett Service Department.

TABLE OF CONTENTS

1. INTRODUCTION

Oven Specifications 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Ventilation Requirements 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Electrical Specifications 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Gas Specifications 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Illustrated Parts Lists 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2. ASSEMBLY

Oven Assembly Procedures 2-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Return Air Diverters 2-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Air Nozzles 2-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Conveyor Rack Assemblies 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Folding Conveyor Assembly 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Air Plates 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

End Plugs 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Conveyor Belt Tensioners 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Crumb Pans 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Mount Remote Control 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

False Front (If Applicable) 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3. OPERATION

Computer Controller 3-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Control Description 3-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Control Operation 3-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Programming Procedures 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Display Information 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sequence of Operation 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Oven Adjustments for Cooking 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Temperature 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Conveyor Speed Time vs. Temperature 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Air Flow Adjustments 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4. CALIBRATION AND ADJUSTMENT

Convection Blower Motors 4-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

To check motor rotation 4-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

To check lowĆlimit 4-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Regulated Gas Pressure 4-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Computer Control Configuration 4-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Temperature Calibration 4-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Belt Speed Calibration 4-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Closed Loop System 4-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Open Loop System - Single belt 4-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TABLE OF CONTENTS

Open Loop System - Twin Belt 4-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Motor Control Board Adjustment 4-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Rerating the Appliance 4-11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Checking the Firing Rate 4-12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5. TROUBLESHOOTING

DC Drive System 5-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Computer Control System 5-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Heating System 5-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Convection System 5-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6. TECHNICAL APPENDIX

Intermittent Ignition System 6-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Principles of Operation 6-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Service Procedures 6-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Servicing the Invent Hood 6-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Illustrated Parts List 6-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cleaning and Maintenance 6-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Servicing Access 6-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Pressure Conversion 6-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Conversion Factors 6-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cooking Computer - Temperature vs Resistance 6-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CHAPTER 1

INTRODUCTION

MT3855

OVEN SPECIFICATIONS

VENTILATION REQUIREMENTS

The hood should completely cover the unit with an overhang of at least 6" (15 cm) on all sides not adjaĆ cent to a wall. The distance from the floor to the lower edge of the hood should not exceed 7' (2.1 m). The ventilation system should replace 80% of the exhaust volume with fresh make up air. TABLE 1 should be used as a guideline.

Single Double Triple

CFM 1000Ć1400 2400Ć3300 3600Ć5000

M3/min 28 Ć 40 68Ć93 102Ć142

TABLE 1

ELECTRICAL SPECIFICATIONS

NOTE: Three Phase hookup is not permitted.

WARNING: DO NOT INSTALL A HIGH LEG" TO ANY CONVEYOR OVEN!

Installations within the U.S.

The MT3855 requires a 15 Amp, 60HZ, 1F, 208Ć240VAC, 4 wire service consisting of L1, L2, neutral and ground. See FIGURE 1. Use 90C wire and size to National Electric or local codes.

Installations outside the U.S.

The MT3855 requires a 15 Amp, 50Hz, 1F, 230 VAC, 3 wire service consisting of L1, neutral and ground. See FIGURE 1. Use 90C wire and size wire according to local codes.

120

208Ć240

OvenSupply

U.S. Installations

220Ć230

OvenSupply

Export Installations

FIGURE 1

MT3855

GAS SPECIFICATIONS

GAS CONNECTIONS

Domestic and General Export installations

The gas line should be large enough to accommoĆ date the peak demand of all the gas appliances. TABLE 2 reflects a straight line, 50 foot run with no coupling restrictions and no other appliances drawing service. Gas line installations MUST conĆ form to National Fuel Gas Code NFPA 54/ANSI Z223.1 Sec. 1.4 (Latest Edition). TABLE 2 should be used as a guideline only.

NOTE: For any pipe runs over 50 feet (15 m), conĆ

sult the factory.

Gas Specifications

Natural Gas Propane Gas

Gas Line Sizing

GAS REQUIREMENTS

The firing rate for the MT3855 is 150,000 BTU/Hr. (43.9 kW/Hr.)

NOTE: For natural gas meter sizing, consult your

local gas company to ensure that your meĆ ter will provide the proper supply.

Installations within the U.S.

1. Add the total BTU's/hr of all the gas appliances.

2. Convert BTU's to cubic ft/hr using the formula Cu Ft/Hr = 1000 BTU/Hr for natural gas.

3. Size the meter accordingly.

Installations outside the U.S.

1. Add the total M3/min of all the appliances.

2. Size the meter accordingly.

Single

Double

Triple

Orifice Size #5 #1/8

Incoming Gas Pressure W.C. kPa mbar W.C. kPa mbar

Static

Operational

5.5"

3/4" line

1Ć1/4" line

1.74

1.36

TABLE 2

17.4

13.7

12.5"

11"

3/4" line

1 line

1Ć1/4" line

3.11

2.73

31.1

27.4

MT3855

ILLUSTRATED PARTS LISTS

ELECTRICAL COMPONENTS

NOTE:  = ASAP Distributor Required Stocking Parts

Ref.

Part

No.

No. Description

Ref.

Part

No.

No. Description

1  M6474 Computer Control Kit, Closed

Loop SB (Qty 1)

1  FW525 Computer Control Kit, Closed

Loop SB (Qty 1) (Reconditioned)

M5635 Computer Control Kit, Open

Loop TB (Qty 1)

M3175 Decal, Lexan Control (Qty 1)

 M7427 Probe, Temperature RTD, 500

OHMS (Qty 1)

M7202 Conversion Kit, Open Loop to

Closed Loop (Qty 1)

M3347 Cable, Computer Control, 25

Pin, 10' (Qty 1)

 M3348 Cable, Computer Control, 9

Pin, 10' (Qty 1)

M3490 Cable, Computer Control, 25

Pin, 50' (Qty 1)

M3491 Cable, Computer Control, 9

Pin, 50' (Qty 1)

 M3349 Harness, Inter-Connecting DC

Drive, 3-Wire (For 9 Pin) (Qty 1)

M3353 Harness, Relay Board

(Open Loop) (For 25 Pin) (Qty 1) (Before 9/15/95)

M7237 Harness, Relay Board (Closed

Loop) (For 25 Pin) (Qty 1) (After 9/15/95)

2 M3314 Bracket, Computer Wall (Qty 1)

M5661 Bracket Assy., Cable Clamp

(Qty 1)

3  M0984 Pick Up, PV-2 (Qty 1) (After

9/15/95)

4 M7236 Board, Relay/Transformer

(Qty 1)

5  22672 Relay, Control (Qty 4)

6  M3352 Transformer, 120V to 24V

(Qty 1)

7  20349 Buzzer, 120V (Qty 1)

NOTE:  = ASAP Distributor Required Stocking Parts

* = Item is Too Large for UPS

8  M3295 Thermostat, High Limit

(Manual Reset) (Qty 1)

9  M1362 Snap Disc, L140/20F, 2 Pole

SPST (Qty 1)

 M2453 Snap Disc, L140/20F, 3 Pole

SPDT (Qty 1)

10  M0595 Switch, Air Pressure SPDT

(Qty 1)

11  M0152 Contact, Emergency Stop

Switch (Qty 1)

12 M3296 Activator, Emergency Stop

Switch (Mushroom Shape) (Qty 1)

M3297 Nameplate, Emergency Stop

(Qty 1)

13 M0593 Terminal Block, 2 Pole (Qty 1or

CE Qty 2)

 M2469 Fan, Axial 110 CFM 4 1/2" (Qty

4) (Before 11/14/95)

22718 Fan Guard & Hardware (Qty 3)

(Before 11/14/95)

 M0572 Cord, Axial Fan 30" Power (Qty

4) (Before 11/14/95)

14  M6381 Blower, Cooling (Qty 1) (After

11/14/95)

15  M3136 Breaker, 7 AMP Circuit (Qty 4)

16  M2772 Breaker, 4 AMP Circuit (Qty 2)

M6590 Plate Assy., Control SB (Qty 1)

M7482 Plate Assy., Control TB (Qty 1)

M1694 Cord Set & Plug Assy., 10 Foot

(Qty 1)

M0772 Receptacle, Twist Lock (Qty 1)

17  M0708 Contactor, 3 Pole, 120V Coil

(Qty 1)

18  M3322 Hood Interlock, Mechanical

(Qty 1)

CONVEYOR COMPONENTS

MT3855

Ref.

Part

No.

No. Description

Ref.

Part

No.

No. Description

19 M6338 Belt, Wire S/S (Total Length

38" SB (Per Foot) MT3870 18 FT, MT3855 16 FT)

M7889 Belt, Wire S/S (Total Length

18-1/2" TB (Per Foot) MT3870 18 FT)

20 M7272 Tensioner (After Assy., Belt

MT3870 (Qty 2) 9/15/95)

21 M2379 Speed Control Board, Bodine

(Qty 1)

M2254 Fuse, Line, 22 Bodine Board, 5

AMP, 125V (Qty 1)

M2316 Fuse, (Qty 1) 23 Armature,

Bodine Board, 200 MA, 250V

24 M3301 Capacitor, (SB Qty 1 or Speed

Control Board TB Qty 2)

25 M2378 Motor, (SB Qty 1 or Conveyor

Drive, Bodine 130V TB Qty 2)

M2500 Brush Set, Bodine (Qty 1)

M0391 Chain, Drive & Order (SB SpecĆ

ify 2 FT or TB Specify 4 FT M0112)

M0112 Masterlink, Drive Chain (Qty 1)

M6791 Guard, Drive 26 Chain SB (Qty

M6482 Guard, Drive Chain TB (Qty 1)

* M3981 Conveyor (Before Assy., Drive

SB MT3870 (Qty 1) 9/15/95)

27 * M6154 Conveyor (After Assy., Drive SB

MT3870 (Qty 1) 9/15/95)

* M3982 Conveyor (Before Assy., Idle

SB MT3870 (Qty 1) 9/15/95)

28 * M6155 Conveyor (After Assy., Idle SB

MT3870 (Qty 1) 9/15/95)

* M7592 Conveyor Assy., Drive TB

MT3870 (Qty 1)

* M7593 Conveyor Assy., Idle TB

MT3870 (Qty 1)

* M4432 Conveyor (Qty 1) Assy., Drive

SB MT3855G (Before 11/14/95)

* M4433 Conveyor (Qty 1) Assy., Idle SB

MT3855G (Before 11/14/95)

* M6777 Conveyor MT3855G Assy.,

Folding (Drive & Idle) SB (Qty

1) (After 11/14/95)

29 M2672 Shaft, Conveyor Drive (Qty 1)

30 M2673 Shaft, Conveyor Idle (Qty 1)

31 M0109 Sprocket, Motor Drive, 12 Tooth

(Qty 1)

M0110 Sprocket, Conveyor Drive, 15

Tooth (Qty 1)

32 M0108 Sprocket, Conveyor Belt, 11

Tooth (Qty 18)

MT3855

CONVECTION COMPONENTS

NOTE:  = ASAP Distributor Required Stocking Parts

Part

Ref.

No.

33 M4224 Motor & Blower Assy. CW

34 M4225 Motor & Blower Assy. CCW

M5419 Motor & Blower Assy. CCW

M2564 Capacitor, Motor MT3870

NOTE: Call factory if MT3855G oven was

manufactured before 2/27/94 to verify motor part number.

M5722 Insulation Kit for Blowers

M7991 Insulation Kit for Blowers

35 M6466 Nozzle Assy. w/ Diverter

M5466 Nozzle Assy. w/ Diverter

M7105 Nozzle Assy. w/ Diverter

M7106 Nozzle Assy. w/ Diverter

Description

MT3870 (Qty 2)

MT3855G (Qty 3) (After 2/27/94)

(Qty 4)

MT3870 (Qty 1)

MT3855G (Qty 1)

MT3870 (Qty 14) Generic

MT3855G (Qty 12) (Before 11/14/95)

MT3855G (Qty 6) (After 11/14/95) (See L-497)

Ref.

Part

No.

M1962 Hold Down, Nozzle MT3870

M7399 Hold Down, Nozzle MT3870

M5486 Hold Down, Nozzle MT3855G

M7380 Hold Down, Nozzle MT3855G

36 M3106 Diverter, Air (LH & RH) MT3870

M3106 Diverter, Air (LH & RH)

M5179 Diverter, Air (LH & RH)

M5453 Diverter, Air (Center) MT3855G

M7372 Diverter, Air (LH) MT3855G

M7374 Diverter, Air (RH) MT3855G

M7373 Diverter, Air (Center) MT3855G

Description

(Qty 1) (Before 9/15/95)

Qty 1) (After 9/15/95)

(Qty 1) (Before 11/14/95)

(Qty 1) (After 11/15/95)

(Qty 2)

MT3855G (Qty 2) (Before 11/14/95)

(Qty 1)(Before 11/14/95)

(Qty 1) (After 11/14/95) (See L-495 & L-496)

AIR PLATES

NOTE:  = ASAP Distributor Required Stocking Parts

Ref.

Part

No.

No. Description

37 M6470 Plate Assy., Air RH MT3870

Generic (Qty 1)

38 M6469 Plate Assy., Air LH MT3870

Generic (Qty 1)

M5767 Plate Assy., Air RH (R to L)

MT3855G Generic (Qty 1)

M5768 Plate Assy., Air LH (R to L)

MT3855G Generic (Qty 1)

M5648 Plate Assy., Air RH (L to R)

MT3855G Generic (Qty 1)

Ref.

Part

No.

No. Description

M5649 Plate Assy., Air LH (L to R)

MT3855G Generic (Qty 1)

24613 Hook, Air Pan (Qty 1)

39 M6597 Plate Assy., Block Off MT3870

Generic (Qty 6)

M6079 Plate Assy., Block Off MT3855G

Generic (Qty 6)

MT3855

GAS BURNER COMPONENTS

NOTE:  = ASAP Distributor Required Stocking Parts

Part

Ref.

No.

40 22132 Burner Assy. Complete (Specify

41 M0767 Blower Motor, Comb. w/ ConĆ

42 M2383 Blower Motor, Combustion

43 M2381 Transformer, 120V to 24V

44 M2382 Relay, Time Delay (Qty 1)

45 M0454 Orifice, Main Burner LP (Qty 1)

45 M0455 Orifice, Main Burner Natural

46 M2727 Pilot Burner & Igniter Assy. LP

46 M2726 Pilot Burner & Igniter Assy.

47 M6378 Shield, Pilot Burner (Qty 1)

48 M0415 Flame Sensor (Qty 1)

49 M2690 Orifice, Pilot LP (Qty 1)

49 M0697 Orifice, Pilot Natural (Qty 1)

50 M0248 Tube, Pilot Aluminum 1/4"

51 M0959 Fitting, Compression 1/4

52 M2799 Union, Compression (Qty 1)

53 21225 Fitting, Elbow (Qty 1)

54 4588 Nipple, Pipe 3/4 x 1-3/8 Close

55 M0280 Tee, 3/4 x 3/4 x 1/4 (Qty 1)

56 M0278 Bushing, 1/4 x 1/8 Hex (Qty 2)

57 M0281 Plug, Pipe 1/8 Black (Qty 2)

58 17874 Ell, Black 1/2 x 3/4 (Qty 1)

59 M0590 Nipple, Pipe 1/2 x 2-1/2

60 M0279 Union, 1/2 Inch Black (Qty 1)

61 1949 Nipple, Pipe 1/2 x 1-3/16

62 M0317 Elbow, 1/2 Inch Street 90 Deg

63 21278 Nipple, Pipe 1/2 x 3-1/2

Description

Model & Gas Type) (Qty 1)

trol Box (Qty 1)

(Qty 1)

Natural (Qty 1)

(1.583 Feet)

(Qty 2)

(Qty 3 or CE Qty 2)

(Qty 1)

Close (Qty 1)

(Qty 1)

Ref.

Part

No.

64 M3238 Tee, 1/2 x 1/2 x 1/4 (Qty 1)

65 23007 Spring, Solenoid Valve, LP to

65 18612 Spring, Solenoid Valve, Natural

23114 Conversion Kit, LP to Natural

21389 Conversion Kit, Natural to LP

M5259 Conversion Kit, LP to Natural

M5290 Conversion Kit, Natural to LP

66 M0282 Valve, Manual Gas (Qty 1)

67 M5495 Dual Solenoid/Pressure ReguĆ

67 22190 Dual Solenoid/Pressure ReguĆ

68 M1054 Spark Box, Johnson (Qty 1)

21242 Connector Kit, Gas Flex 48"

21826 Connector Kit, Gas Flex 36"

69 M7280 Flame Tube Assy., MT3870

M7390 Flame Tube Assy., MT3855G

Description

Natural (Qty 1)

to LP (Qty 1)

MT3870 (Qty 1)

MT3855G (Qty 1)

lator, Nat 24V (Qty 1)

lator, LP 24V (Qty 1)

(Qty 1)

MT3855

EXTERIOR COMPONENTS

NOTE:  = Doors are not returnable

Part

Ref.

No.

 M2868 Door Assembly, Pull Down S/S

M2188 Handle Kit, Door 2" (used

70  M3944 Door Assembly (used w/ false

71 M4275 Handle Kit, Door 22" (used w/

72 M1871 Plate, RH Pivot Slotted (Qty 1)

73 M1872 Plate, LH Pivot Slotted (Qty 1)

74 M3602 Bracket Assy., Mounting (Qty 2)

75 M3603 Bracket Assy., Mounting (Qty 2)

M5475 Filter Assy., MT3855G (Qty 1)

76 M3751 False Front Assy., MT3870

M4563 False Front Assy., MT3855G

M3751 Tape, Closed Cell Foam

M5032 Chimney Kit, Single (Qty 1)

M7464 Chimney Kit, Single (Qty 1)

M7160 Chimney Kit, Double (Qty 1)

M7463 Chimney Kit, Double (Qty 1)

21390 Legs, 17-1/4" w/ Casters

21391 Legs, 23-1/4" w/ Casters

14444 Casters, Cradle (Triple Oven)

77 M3783 Stop, Product S/S (Qty 1)

78 M3779 Extension Assy., Product 6"

M4223 Extension Assy., Product 10"

Description

(used w/enclosed Greenheck hood system) (Qty 1)

w/M2868) (Qty 1)

front) (Qty 1)

M3944) (Qty 1)

(Before 11/14/ 95)

(Qty 1)

(Before 11/95)

(After 11/95)

(Before 11/95)

(After 11/95)

(Double) (Set of 4)

(Single) (Set of 4)

(Set of 4)

(Qty 1)

Ref.

Part

No.

M7575 Extension Assy., Product 15"

M2824 Crumb Pan, Idle MT3870

79 M6168 Crumb Pan, Idle MT3870

M2823 Crumb Pan, Drive MT3870

80 M6167 Crumb Pan, Drive MT3870

M6910 Crumb Pan, Idle MT3855G

M6906 Crumb Pan, Drive MT3855G

M5612 Plug Assy., Lower RH MT3870

81 M7276 Plug Assy., Lower RH MT3870

82 M5612 Plug Assy., Lower LH MT3870

M7386 Plug Assy., Lower MT3855G

83 M3116 Plug Assy., Upper MT3870 &

84 M2460 Air Curtain, Upper End Plug

M3728 Support Assy., Upper End Plug

M3729 Support Assy., Upper End Plug

M7149 M7150

85 M3724 Handle, End Plug (Qty 2)

22229 Stacking Assy., Double (Qty 1)

M4633 Panel & Filter Assy. (Qty 1)

Description

(LaRosa's) (Qty 1)

(Qty 1) (Before 9/15/95)

(Qty 1) (After 9/15/95)

(Qty 1) (Before 9/15/95)

(Qty 1) (After 9/15/95)

(Qty 1)

Qty 1) (Before 9/15/95)

(Qty 1) (After 9/15/95)

(Qty 1)

(Qty 2)

MT3855G (Qty 2)

(Qty 2)

RH MT3870 (Qty 2)

LH MT3870 (Qty 2)

Support Assy., Upper End Plug RH MT3855G (Qty 2) Support Assy., End Plug LH MT3855G (Qty 2)

MT3870 (All) & MT3855G (Before 11/14/95)

MT3855

Ref.

Part

No.

No. Description

Ref.

Part

No.

No. Description

M5485 Panel & Filter Assy. MT3855G

(Qty 1) (After 11/14/95)

XXXXX Control Box Cover w/ Louvers

MT3855G (Qty 1) (Before 11/14/95)

M6799 Control Box Cover w/ Access

Door MT3855G (Qty 1) (After 11/14/95)

XXXXX Control Box Cover w/ Louvers

MT3870 (Qty 1) (Before 9/15/95)

86 M7266 Control Box Cover w/ Access

Door MT3870 (Qty 1) (After 9/15/96)

87 M6035 Latch, Access Door (Qty 1)

M2689 Body Back, MT3870 (Qty 1)

(Before 9/15/95)

M7254 Body Back, MT3870 (Qty 1)

(After 9/15/95)

M4248 Body Back, MT3855G (Qty 1)

MT3855

EXCLUSIVE TO EXPORT

NOTE:  = ASAP Distributor Required Stocking Parts

Ref. No.

88 M2276 Burner Assy., Complete

89 M4597 Motor & Blower Assy., CW

90 M4598 Motor & Blower Assy., CCW

91 M6000 Dual Solenoid/Pressure

91 M6001 Dual Solenoid/Pressure

92 M7283 Blower, Cooling Export (Qty 1)

93 M3128 Motor, Conveyor Drive

94 M3153 Digital Speed Control Board,

95 M2630 Fuse, Line, Bodine Board, 500

96  M2316 Fuse, Armature, Bodine

97 M7282 Board, Relay (Closed Loop)

98 M6025 Fuse, 25V 80 ma (Qty 1)

99 M6024 Transformer, 220V to 24V

100  20350 Buzzer, 240V (Qty 1)

101 R1580 Stop, End (Qty 1)

102 M6449 Filter, Noise (Qty 1) CE

103 M7880 Computer Control Kit, Closed

104 M7888 Relay, 1 Second Time Delay

105 M2386 Blower Motor, Combustion

106 M7333 Pilot Burner & Ignitor Assy.,

106 M7334 Pilot Burner & Ignitor Assy.,

107 M2497 Switch, Push Button (Qty 1)

Part No.

M5717 Board, Relay (Open Loop) SB

Description

(Qty 1)

MT3870 (Qty 2)

Regulator, Nat. (Qty 1)

Regulator, LP (Qty 1)

Bodine, 180V (Qty 1)

Bodine (Qty 1)

MA (Qty 1)

Board, 200 MA, 250V (Qty 1)

(Qty 1)

SB (Qty 1)

(Qty 1)

Loop SB (Qty 1) CE

(Qty 1) CE

LP (Qty 1) CE

Nat. (Qty 1) CE

Ref. No.

108 M2498 Switch, Contact (Qty 1) CE

109 M3330 Switch, Air Pressure DifferenĆ

110 M0706 Orifice, Main Burner (Specify

111 R0164 Terminal Block, Power (Qty 2)

112 R0166 Terminal Block, Ground

113  M3168 Spark Box, 240V (Landis &

114  M2247 Contactor, 240V, 50 HZ (Qty 1)

115 XXXXX Indicator Light (Qty 2) CE

116 16037 Indicator Light, 250V, Red,

117 16775 Relay, SPST, 240V, 30 Amp.

118 M3172 Timer, Fixed, 2 Second (Qty 1)

119 M3173 Timer, Fixed, 10 Second (Qty

120 M6029 Connector, Liquid Tight (Qty

121 10809 Nipple, Pipe 1/2 x 2 (Qty 1)

122 M2835 Fitting, Elbow 90 Street 1/8"

123 M3443 Bushing, Adapter (Qty 2) CE

124 M2841 Fitting, Pressure Tap (Qty 2)

Part No.

M2819 Switch, Air Pressure (in/wc)

18265 Indicator Light, 28V, Red,

M6589 Plate Assy., Control SB (Qty 1)

M7323 Plate Assy., Control SB Qty 1)

M6982 Piping Assy. (Qty 1) CE

Description

tial (mbr) (Qty 1) CE

(Qty 1) Australia

MTD) (Qty 1) CE

(Qty 1) CE

Gyr) (Qty 1) CE

Round (Qty 1) CE

Round (Qty 1) CE & Australia

(Qty 1) CE

1) CE

Australia

1) CE

(Qty 1) CE

MT3855

MT3855 CONTROL BOX

(Control Plate and/or Gas Burner Components not Shown)

MT3855

MT3855 GAS BURNER COMPONENTS

(Control Box not Shown)

MT3855

MT3855 SB CONTROL PLATE ASSY

(M6590)

MT3855

MT3855 EXTERIOR OVEN VIEW

CHAPTER 2

ASSEMBLY

MT3855

OVEN ASSEMBLY PROCEDURES

RETURN AIR DIVERTERS

For units manufactured prior to 11/14/95

1. Slide the return air diverters into the oven and clip to the lower rear of the baking cavity. The edge of the diverter should be 3" (7.6 cm) from the outside edge of the oven cavity.

IMPORTANT:

Note Orientation Of Return Air Diverters!

FIGURE 1

For units manufactured after 11/14/95

1. Lift the front end of the diverter and slide the clips up and behind the rear oven wall.

2. Lower the front end and slide the diverter into place. Be careful to install the diverters in the correct order as shown in FIGURE 2. Make sure that the edges of the end diverters line up with the cutout in the rear oven wall.

AIR NOZZLES

1. Install the nozzles from the center of the oven to the ends. The bottom of the nozzle must fit into the slot of the nozzle support located at the front of the oven.

2. Secure the nozzle holdĆdown strip across the inside front of the oven using the existing screws attached to the oven wall.

M7105

End Plug

Nozzle M7105 is

identified by one

hole in flange at

open end

M7106

TOP VIEW OF OVEN

End Plug

Nozzle M7106 is identified by two holes in flange at open end

Diverter

M7273

End Plug End Plug

TOP VIEW OF OVEN

Inner Diverter M7373

Diverter M7374

FIGURE 2

FIGURE 3

MT3855

CONVEYOR RACK ASSEMBLIES

For units manufactured prior to 11/14/95.

1. Slide the drive side conveyor rack assembly (with the sprocket on the end of the shaft) into the support tracks.

2. Push until the end sprocket is inserted into the control compartment.

3. Install the alignment bolt through the conveyor and control box.

4. Slide the idle side conveyor rack assembly into the support tracks from the exit end of the oven.

WIRE CONVEYOR BELT

NOTE: The conveyor belt has loops on all four

sides. The belt must be installed so the loops travel as shown in FIGURE 4.

1. Thread the wire belt from the right side of the oven, lower level first.

2. After pushing the belt through on the lower levĆ el, leave about 12" (30.5 cm) hanging out on the left side.

3. Take the remainder of the belt, loop it around the right shaft, and push it through on the upĆ per level. The two ends of the belt should be approximately 6Ć9" (15Ć22 cm) past the left shaft (right shaft if right to left travel is required) on the upper level of the belt support.

Side Belt Loops

4. Install the inner and outer master links as shown in FIGURE 5.

Master Link

Direction of

Travel

FIGURE 5

Unless otherwise specified, the conveyor travel is factory set for leftĆtoĆright operation when facing the front of the oven. If a direction change is reĆ quired, the polarity of the drive motor must be reĆ versed. To change the polarity of the drive motor, disconnect the oven from the power source and inĆ terchange the black and white motor leads at the D.C. Controller Board located within the control box. If the polarity of the motor is changed to

rightĆtoĆleft belt travel, the conveyor belt must be installed from the left side of the oven inĆ stead of the right side.

NOTE: Change the air plates whenever the conĆ

veyor belt direction of travel is changed. See FIGURE 6.

FIGURE 4

Direction of

Travel

DRIVE CHAIN

1. Install the drive chain around the drive motor and then around the sprocket on the conveyor belt support.

2. Push the conveyor motor back to tighten the drive chain.

3. Lock the motor into position by tightening the four 1/4Ć20 hex head screws between the conĆ veyor motor and the control box.

MT3855

FOLDING CONVEYOR ASSEMBLY

END PLUGS

For units manufactured after 11/14/95

The conveyor must be installed from the left side (control box side) of the oven.

1. Unfold the conveyor while inserting it into the support tracks. Be careful to avoid hitting the

emergency off switch on the side of the conĆ trol box.

2. Insert the conveyor in beyond the normal restĆ ing position.

3. Install the drive chain around the drive motor sprocket and the conveyor sprocket.

4. Pull the conveyor back out of the oven until the 1/4Ć20 thumb screw can be installed through the conveyor support and into the control box bracket.

NOTE: If the mounting hole cannot be lined up or

the chain is too loose, the drive motor will need to be repositioned.

AIR PLATES

Verify that the proper air plates were received. InĆ spect the orientation of the air plates. Refer to FIGURE 6.

1. Install the upper end plug support brackets at both ends of the oven.

2. Install the upper and lower end plugs at both ends of the oven.

CONVEYOR BELT TENSIONERS

For units manufactured prior to 11/14/95.

Each tensioner installs between the idle end of the conveyor (the side opposite the drive) and the oven's body side.

1. Compress the spring by hand to engage the tensioner pin with the hole in the oven's body side. (Refer to FIGURE 7).

Oven Body Side

NOTE: Standard air plates shown. Alternate plates

available for some installations.

Left Air Plate P/N M5767

Right Air Plate P/N M5768

FIGURE 6

FIGURE 7

CRUMB PANS

1. Install the crumb pans under each end of the conveyor.

MOUNT REMOTE CONTROL

1. Mount the remote control unit on a wall within reach of the computer cables.

2. Connect the computer cables from the controlĆ ler's rear connector to the connector located at the rear of the oven.

FALSE FRONT (IF APPLICABLE)

Hang false front. Install door handle.

CHAPTER 3

OPERATION

MT3855

COMPUTER CONTROLLER

45678

FIGURE 1

CONTROL DESCRIPTION

1. DIGITAL DISPLAY - Displays the time, temĆ perature and controller related information.

2. OVEN ON/OFF - Controls power to the oven.

3. NUMERIC KEYS - Used to enter numerical data in the programming mode.

4. CLEAR KEY - Used to clear the display if an error is made in the programming mode.

5. SET TEMP KEY - Used to view or program the temperature setpoint.

6. ACT TEMP KEY - Used to view the current oven temperature.

7. TIME KEY - Used to view or program the cook time.

8. PROG/ENTER KEY - Used to enter and exit the programming mode. Also used to lock in programmed settings.

9. STATUS LAMPS - When lit indicate that the fan or burners are operating.

This oven, supplied with remote control, is equipped with an emergency shut down switch. Should you need to stop the belt, fans, or heat press the emergency switch.

Do not use the emergency switch as a GENERAL on/off switch!

CONTROL OPERATION

To turn the oven on:

1. Press and hold the ON/OFF key (2). The disĆ play reads OFF when the oven is idle.

2. The display flashes WAIT  LOW  SET  TIME 

mmss.

3. The FAN and HEAT status lamps (9) light. The fans begin to run. The heat rises to the proĆ grammed temperature. The conveyor belt travels at the programmed speed.

To view the cook time setting:

1. Press the TIME key (7). The LED on the key lights and the display flashes SET  TIME 

mmss.

To display the actual oven temperature:

1. Press the ACT TEMP key (6). The LED on the key lights and the display reads ACTUAL 

nnnnF.

To view the temperature set point:

1. Press the SET TEMP key (5). The LED on the key lights and the display flashes SET  TEMP

 nnnnF.

To turn the oven off:

1. Press the ON/OFF key (2). The blower moĆ tor(s) continue to run regardless of the controlĆ ler status until the temperature drops below 180F (82C).

MT3855

PROGRAMMING PROCEDURES

DISPLAY INFORMATION

Programming the Cook Time:

1. Press the PROGRAM/ENTER key (8).

2. Press the TIME key (7). The display reads

PROGĆ?  SET  TIMEĆ?  _ _ _ _.

3. Use the NUMERIC keys (3) to enter the desired cook time. The display will read the numbers as they are entered. If an error is made, press the CLEAR key (4) and reĆenter the number.

4. Press the PROGRAM/ENTER key (8) a second time to lockĆin the new time. The new cook time will be stored in the computer's memory.

Programming the Temperature:

1. Press the PROGRAM/ENTER key (8).

2. Press the SET TEMP key (5). The display reads

PROGĆ?  SET  TEMPĆ?  _ _ _ _F.

3. Use the NUMERIC keys (3) to enter the desired temperature set point. The control displays the numbers as they are entered. If an error is made, press the CLEAR key (4) and reĆenter the number.

4. Press the PROGRAM/ENTER key (8) a second time to lockĆin the new temperature. The new temperature setpoint will be stored in the comĆ puter's memory.

Operation at the Programmed Settings:

 WAIT  LOW - indicates that the present oven

temperature is lower than the set point temperĆ ature. When the oven reaches the set point temperature the display changes to READY.

 READY - indicates that the oven is ready to acĆ

cept product.

 SET  TIME  mmss - indicates the current

cook time setting.

 HIGH  TIME - indicates that the temperature

is well above the set point. This usually occurs when moving from a higher āto a lower temperaĆ ture. Wait until the display reads ready before loading product.

 HIGH  TEMP  LIMIT - indicates that the oven

temperature exceeds the high limit from the 2nd level program. The Over Temperature Alarm buzzer will sound. Shut the oven off and wait for the unit to cool down.

 HIGH  TEMP  PANEL - indicates that the conĆ

trol area reaches an excessive temperature. Shut the oven off and wait for the unit to cool down.

 PROBE  OPEN  PROBE  SHORT - indicates

that the temperature sensor has failed. The Alarm buzzer sounds. Shut the oven off and contact a service representative.

1. Press and hold the ON/OFF key (2).

2. The FAN and HEAT status lamps (9) light. The fans begin to run. The heat rises to the temperĆ ature setting stored in the computer's memory. The conveyor belt begins to travel at the timed speed stored in memory.

3. The display will flash WAIT  LOW  SET  TIME

 mmss until the programmed bake temperaĆ

ture is reached. The HEAT lamp (9) will remain lit until the oven reaches the temperature set point.

4. The display reads READY and the HEAT lamp (9) goes out.

5. The oven is now ready to accept product.

6. Press and hold the ON/OFF key (2) to turn the oven off. The fans continue to run while the oven cools to a safe temperature.

MT3855

SEQUENCE OF OPERATION

COMPONENT REFERENCE

NOTE: Refer to FIGURE 2 for component locaĆ

tions.

1. COOKING COMPUTER

2. BURNER VALVE RELAY

3. BLOWER RELAY

4. MAIN CONTROL RELAY

5. SPEED CONTROL BOARD

6. SINGLE POLE SINGLE THROW THERMAL SWITCH

7. MANUAL RESET HIGH LIMIT SWITCH

8. CONVECTION FAN PRESSURE SWITCH

9. TRANSFORMER

10. COMBUSTION MOTOR

11. RELAY

12. CENTRIFUGAL SWITCH

13. IGNITION CONTROL MODULE

14. PILOT VALVE

15. MAIN VALVE

16. MOTOR CONTACTOR

17. CONVECTION FANS

18. COOLING BLOWER

19. SINGLE POLE DOUBLE THROW THERMAL SWITCH

OPERATION

1. Apply power to the oven. Program the time and temperature into the computer (1). The burner valve relay (2), blower relay (3) and main conĆ trol relay (4) energize powering up the oven.

2. The main control relay (4) sends power to the speed control board (5) and the single pole single throw thermal switch (6). If this switch is closed, power will be supplied to the manual reset high limit switch (7). If this switch is closed power flows to the convection fan presĆ sure switch (8).

NOTE: The convection fan pressure switch (8)

will close only if the convection fans are operating and putting a positive pressure on the switch.

When this switch closes power goes to the priĆ mary side of the transformer (9) located inside of the box mounted on top of the combustion motor (10). When the relay (11) mounted in the same box is energized the combustion motor (10) should start.

3. Next the centrifugal switch (12) in the motor closes sending 24 volts to the ignition control module (13). This powers up the pilot valve (14). After the pilot valve is lit and the pilot flame is established through rectification, then termiĆ nal three of the ignition control module (13) will send 24 volts to the burner valve relay (2). If this relay is closed, power goes to the main valve (15) allowing it to open and send gas into the burner for ignition.

4. The blower relay (3) sends 115 volts to the coil of the motor contactor (16). Once energized the three convection fans (17) in the rear of the oven and a cooling blower (18) located in the combustion burner compartment start. There is also a single pole double throw thermal switch (19) in this circuit that allows the cooling blower to come on when the oven is turned off just in case the convection fan compartment should overheat.

MT3855

FIGURE 2

MT3855

OVEN ADJUSTMENTS FOR COOKING

TEMPERATURE

The internal temperature of your product is very imĆ portant; and should be taken as soon as the prodĆ uct completely exits the cooking chamber. This reading will give a general indication of whether or not the product is fully cooked. A multiple topping pizza, for example, will be cooked if the internal temperature is over 160Ć165F (64Ć67C). For a single topping, such as cheese, the temperature should be greater than 170Ć180F (69Ć74C).

CONVEYOR SPEED TIME VS. TEMPERATURE

Typically, as the temperature increases, the time decreases. Conversely, as the temperature deĆ creases, the time increases. To find a good bake time and temperature, one or the other should reĆ main constant. For example, if the temperature is set at 480F (224C) and the belt speed is set at 7 minutes 30 seconds, but the pizza is not as brown as desired, keep the time setting the same and inĆ crease the temperature to 500F (234C).

AIR FLOW ADJUSTMENTS

Since a variety of products can be cooked in this oven, special settings for air flow must be made for your product. Unless otherwise specified, Blodgett Mastertherm conveyor ovens are shipped from the factory with only partial air flow above the conĆ veyor. This means that most of the air flow holes are blockedĆoff" via steel strips which stop the heated air from reaching the item being cooked. These strips or blockĆoff plates" can be easily relocated to regulate the amount of air for your particular needs. The area below the belt has all air flow holes open.

EXAMPLE:

A good bake time and temperature have been esĆ tablished, but more browning on top of the pie is desired. Relocate one of the blockĆoff plates" above the belt to open a few rows of holes toward the exit end of the oven. This will allow more of the superheated air to brown the top just prior to exitĆ ing the oven.

EXAMPLE:

The bottom of the pie is golden brown, but the top is a little too dark. Closing off some of the air flow from the top at the exit end of the oven will cure this problem. Leave the time and temperature at the same settings.

EXAMPLE:

The top of the pie is too dark, but either the bottom is not done enough, the center of the pie is doughy, or the ingredients are not fully cooked. Open some of the rows of holes above the conveyor at the entry half of the oven and close off the holes at the exit. This will allow the superheated air to penetrate the pie from the top and bottom (at the beginning of the cooking cycle) quicker. As a result the center of the crust and/or ingredients will be cooked before the pie starts the browning stage. Leave the time and temperature at the same settings.

WARNING!!

In the event of a power failure, all switches should be turned off, and no atĆ tempt should be made to operate the appliance until power is restored.

In the event of a shut-down of any kind, allow a five (5) minute shut off period beĆ fore attempting to restart the oven.

Here are some suggestions for setting up the air flow. Keep in mind that the first half of the oven is used for the initial baking of the product and the last half is used for browning. We will use pizza as an example.

CHAPTER 4

CALIBRATION AND

ADJUSTMENT

MT3855

CONVECTION BLOWER MOTORS

TO CHECK MOTOR ROTATION

1. Remove the back of the oven body and verify proper motor rotation. (See FIGURE 1)

For motor placement, the direction of rotation is viewed from the oven's rear and working from left to right, beginning at the control box. In most cases, the motor direction is referenced to the end of the shaft (EOS). However, due to the vertical poĆ sitioning of the motors in Mastertherm ovens, it is more instructive to reference the end of the motor (EOM) as looking from the rear of the oven. In FIGURE 1 all directions are taken from EOM. The correct rotation amperage draw is approximately 1 amp. If the measured amperage is less than .5, check for proper motor rotation direction.

(Side view rotation of Blower Wheel)

Slinger

Cooling

Blade

Blower

Motor

TO CHECK LOWĆLIMIT

1. Turn the oven on and let it heat up to approxiĆ

mately 200F (93C).

2. Shut the oven off. The blowers should come back on in several seconds.

3. Wait for the blowers to shut off.

4. Once the blowers are off, turn the oven back on. Press the ACT TEMP" key to verify that the blowers shut off between 135F (57C) and 170F (77C). If the blowers do not shut off reĆ fer to the Troubleshooting section page NO TAG.

Slinger

Cooling

Blade

Blower

Motor

Control

Box

Motor #1 Motor #2

(Top view rotation of Blower Wheel)

Motor #1

CCW

Motor #2

CCW

FIGURE 1

Motor #3

Control

Box

Motor #3

CCW

MT3855

REGULATED GAS PRESSURE

1. Let the oven run up to 510F (266C).

2. Set the time to 7 minutes. You may now verify the operational and regulated gas pressures.

Incoming static gas pressure to the unit, with all the gas appliances drawing from the supply, should be a minimum of 5.5" W.C. (13.7 mbar) for natural gas and 11" W.C. (28 mbar) for propane gas. The manĆ ifold pressure, if measured after the regulator loĆ cated inside the control box, must be 3.5" W.C. (9 mbar) for natural gas and 10" W.C. (25 mbar) for propane gas.

The pressure can be checked at the tap on the dual regulated gas valve or at the tap on the tee valve. If pressure adjustments are needed, turn the adĆ

Pressure

Ta p

Regulator Cap

Regulator

Adjustment

justing screw located under a screw cap on the left front side of the dual regulated valve. Adjust the gas pressure by turning the screw clockwise to raise the gas pressure and counterĆclockwise to lower the gas pressure. Be sure to reinstall the screw cap; should the diaphragm rupture this cap acts as a flow limiter

The air shutter disc on the burner blower motor, loĆ cated inside the control box at the top of the asĆ sembly, is factory adjusted to provide the most effiĆ cient blue flame possible at sea level. Visually examine the flame to verify it's quality. Should it need adjustment, increase or decrease the air mixĆ ture to attain the best flame quality.

Pressure Tap

Inlet

Regulator

Cap

Regulator

Adjustment

Outlet Pressure Ta p

Pressure Regulator (U.S. models)

Pressure Regulator (Some export models)

FIGURE 2

MT3855

COMPUTER CONTROL CONFIGURATION

INITIATING ACCESS MODE

The Cooking Computer provides a special Access Mode for setting and displaying certain computer special functions. To initiate the Access Mode place the control in the OFF state, (OFF is shown in the display when power is first applied to the control). Press the following sequence of keys to set the control to Access Mode: CLEAR 1 2 3 4 5 6 ENTER. The display will show ACCESS.

DISPLAY ACTION

DISPLAY ACTION TAKEN

TAKEN

F/CMODE? Press

POS OFFSET? Press

NEG OFFSET? Press

MAXĆT ENTRY? Press

PROG

T  F(C)

ENTER

PROG

0(0) Press

ENTER

PROG

0(0) Press

ENTER

PROG

600(315) Press or change then

ENTER

CONFIGURATION

When the controller is in the ACCESS" mode, press the following buttons: CLEAR 1 1 1 ENTER. With the exception of the positive and negative offĆ sets, to be addressed later, all display data should correspond to the entries in the chart below. If the data does not match the chart, it should be changed accordingly. When the correct data is disĆ played press the PROG/ENTER key, the display will cycle on to the next screen. If a step is missed, press the CLEAR button to backup.

Press again or hit any number and

press again.

PROG

ENTER

PROG

ENTER

PROG

ENTER

PROG

ENTER

it will change.

MAXĆT LIMIT? Press

READY BAND? Press

MINĆHT ON? Press

DISPLAY INTEG? Press

TĆCTRL INTEG? Press

PROG

625(330) Press

ENTER

PROG

10 Press

ENTER

PROG

60 Press

ENTER

PROG

30 Press

ENTER

PROG

10 Press

ENTER

TABLE 1

PROG

ENTER

PROG

ENTER

PROG

ENTER

PROG

ENTER

PROG

ENTER

MT3855

Boost Option - (versions 2.00 or 3.00)

When the controller is in the ACCESS" mode, press the following buttons: CLEAR 2 1 2 ENTER to enter the boost option.

DISPLAY

ACTION

DISPLAY ACTION TAKEN

TAKEN

BOOST / MODEĆ? (Flash alternately)

Press

PROG

ENTER

OPTĆ1 or OPTĆ2

Select OPTĆ1 to turn off boost mode.

OPTĆ1 Press

PROG

ENTER

DONE SAVE EXIT

EXITING THE ACCESS MODE

After pressing PROG/ENTER the last time, the disĆ play will show EXIT" then beep and return to the ACCESS" mode. Pressing and holding the ON/ OFF key will turn the oven on. A new time and temĆ perature must be entered upon exiting the ACĆ CESS" mode since the oven will automatically default to 0. The oven will not fire until both time and temperature are entered.

TABLE 2

Press any numeric key to toggle between OPTĆ1 and OPTĆ2

Press

PROG

ENTER

Firmware Model Version Display

Password: CLEAR 1 2 3 ENTER

MODEL Ć Computer Model Number - 6028 (Blodgett Conveyor Oven With Speed Control)

SWĆVER Ć Firmware version number. VĆxxyy xx = major version, yy = minor version

DATEĆ? ĆFirmware release date

CHKSUM Ć ROM checksum stored in PROM. xxxx Ć Value is display in hexadecimal format.

MT3855

TEMPERATURE CALIBRATION

TO ENTER THE CALIBRATION MODE

1. Press the ON/OFF key until OFF is displayed.

2. Press CLEAR 1 2 3 4 5 6 ENTER to enter the access mode. The display reads ACCESS.

3. Press CLEAR ACT_TEMP ACT_TEMP ACT_TEMP ENTER to access the Temperature Calibration mode.

4. Disconnect the white wire from the D.C. motor. Secure so the wire will not ground against any part of the oven. This will disable the conveyor.

NOTE: Disregard the controller display. The only

numbers of concern are the pyrometer reading and the temperature set point.

TO CALIBRATE THE OVEN TEMPERATURE

During operation, the temperature control is based on the measured temperature and the temperaĆ ture offset which is programmed into the control. If the temperature measured in the center of the oven is below the oven setpoint a positive offset is needed. If the temperature measured in the center of the oven is above the oven setpoint a negative offset is needed.

NOTE: In the calibration mode the display gives

the current measured temperature only.

To view the current temperature setpoint:

1. Press the SET_TEMP, key.

To change the temperature setpoint :

1. Press PROG/ENTER SET_TEMP.

2. Enter the desired setpoint.

3. Press the PROG/ENTER key.

To program the temperature offset:

To change the temperature calibration a positive or negative offset must be programmed.

1. Press PROG/ENTER followed by ACT_TEMP. The display flashes either POS * OFFSET or

NEG * OFFSET

NOTE: POS OFFSET is displayed if a value has

been programmed in for a positive offĆ set. NEG OFFSET is displayed if a valĆ ue has been programmed for a negaĆ tive offset. The only time both will be displayed is if a value of 0 has been enĆ tered for both.

2. Enter a value for the desired offset. The display flashes DISPLAY * INTEG?.

3. Press the PROG/ENTER key. The default value of 30 will be displayed.

4. Press the PROG/ENTER key. The display will flash TĆCTRL * INTEG?.

5. Press the PROG/ENTER key. The default value of 10 will be displayed.

6. Press the PROG/ENTER key.

The control will now resume using the new paramĆ eters.

Verify the temperature calibration once the unit has cycled for 5 minutes with the new settings. Repeat calibration using a new offset value if necessary.

TO EXIT THE CALIBRATION MODE

1. Press the CLEAR key twice.

2. The display flashes REBOOT then displays the set time and temperature. You must reĆenter a temperature for the oven to start heating again.

A.) Press PROG/ENTER SET_TEMP

B.) Enter the desired temperature.

C.) Press the PROG/ENTER key. The heat

light turns on and the burner begins to cycle at set point.

MT3855

BELT SPEED CALIBRATION

CLOSED LOOP SYSTEM

To enter the calibration mode:

1. Press the ON/OFF key until OFF is displayed.

2. Press CLEAR 1 2 3 4 5 6 ENTER to enter the Access mode. The display reads ACCESS.

3. Press CLEAR TIME TIME TIME ENTER to acĆ cess the Belt Speed Calibration mode. The disĆ play flashes INIT.

Belt speed calibration:

1. OVEN LENGTH - Set the length of the conveyĆ or belt using the information from TABLE 3.

2. MOTOR RATIO - Set the motor gear ratio from the information from TABLE 3.

3. SHAFT TEETH - Set the shaft teeth number from the information from TABLE 3.

4. MOTOR TEETH - Set the motor teeth number from the information from TABLE 3.

5. BELT RADIUS - Set the belt radius from the inĆ formation from TABLE 3.

NOTE: The values given are estimates. If you

reenter the calibration mode after setĆ ting the belt speed, the belt radius may differ from the table.

6. The display gives a four digit value followed by the letter K. Press ENTER twice to verify the belt time.

Belt speed verification:

1. ENTER TEST TIME - Enter a test time to verify the belt speed. The default setting is 7 minutes.

2. WAIT - 1 second delay before the belt moves.

3. ENTER ACTUAL TIME - Place an object on the belt. Note the time from entrance to exit. Enter the actual measured time.

4. ENTER TEST TIME - If the actual measured time is not within 5 seconds of the test time, reĆ peat the belt verification test to obtain better accuracy. If the actual measured time is acĆ ceptable, press the CLEAR key to continue the belt speed calibration.

5. MAX/MIN CALC TIME - The control sets the fastest and slowest cook time the user can proĆ gram. This requires a 1 minute delay in the calĆ ibration process.

NOTE: If the control cannot read the shaft enĆ

coder the display reads ERROR then ABORT before exiting belt calibration. Verify the connection of the encoder Restart the belt speed calibration.

6. The display flashes MIN SET TIME? Press the PROG/ENTER key to display the calculated minimum set time. Press the PROG/ENTER key to accept this value or enter a new time with a value higher than the default. Press PROG/ENTER again to accept.

7. The display flashes MAX SET TIME? Press the PROG/ENTER key to display the calculated maximum set time. Press the PROG/ENTER key to accept this value or enter a new time with a value lower than the default. Press PROG/ENTER again to accept.

8. The display reads DONE.

To save the new belt speed:

1. Press ENTER to save the belt speed calibraĆ tion program in the control's memory.

Oven Type Oven Length Motor Ratio Shaft Teeth Motor Teeth Belt Radius

MT3870 70 600 15 12 8,712

MT3855 55 600 15 12 8,712

MT3270 70 600 15 12 8,712

MT3240 40 600 15 12 8,893

MT2136 36 600 15 12 8,712

MT1828 28 600 24 24 7,209

TABLE 3

MT3855

OPEN LOOP SYSTEM - SINGLE BELT

To enter the calibration mode:

1. Press the ON/OFF key until OFF is displayed.

2. Press CLEAR 1 2 3 4 5 6 ENTER to enter the Access mode. The display reads ACCESS.

3. Press CLEAR TIME TIME TIME ENTER to acĆ cess the Belt Speed Calibration mode. The disĆ play flashes INIT.

Belt speed calibration:

1. The display reads BELT SIZE-?. Enter the length of the conveyor belt for your model. See TABLE 4. Press the PROG/ENTER key.

2. The display reads STEP-1. The controller is in Step 1 of the calibration procedure: maximum belt speed. The motor control is automatically set to its maximum output. Place an object on the belt and note the time from entrance to exit.

NOTE: Be certain to measure either the leadĆ

ing edge in and out or the trailing edge in and out. Do not use the leading edge in and the trailing edge out.

A.) The display reads STEP-1TIME-?. Enter

the time measured in STEP-1. Min: 0 Max: 59:59 (min:sec). Press the PROG/ ENTER key.

B.) The display reads STEP-1DIST-?. Enter

the belt length for your model. See TABLE 4. Press the PROG/ENTER key.

3. The display reads STEP-2. The controller is in Step 2 of the calibration procedure: minimum belt speed. The motor control is automatically set to its minimum output.

The belt will travel very slowly during this part of the calibration procedure. To minimize the time spent on STEP-2, measure off 10" on the conveyor support. Place an object on the belt and note the travel time for the 10" measured distance.

A.) The display reads STEP-2 TIME-?. Enter

the measured travel time for STEP-2. Min: 0 Max: 59:59 (min:sec). Press the PROG/ ENTER key.

B.) The display reads STEP-2 DIST-?. Enter

10". Press the PROG/ENTER key.

4. The display reads MIN-TM ENTRY? (the fastĆ est belt speed). Limits of this value are deterĆ mined by the Step-1 and Step-2 calibration values. See TABLE 4 for correct entry for this model. Press the PROG/ENTER key.

5. The display reads MAX-TM ENTRY? (slowest belt speed). Limits of this value are determined by the Step 1 and Step 2 calibration values. Use 1600 (16 min). Press the PROG/ENTER key.

6. The display flashes DONE and SAVE. Press the PROG/ENTER key to permanently store the calibration values in nonĆvolatile memory (NOVRAM).

NOTE: During these adjustments, pressing the

clear button will abort all entries and reĆ quire reprogramming of belt time mode. When exiting the Belt Speed Calibration Mode, enter a time. Otherwise the time deĆ faults to zero and the oven will not heat, and the belt will not move.

Oven

Type

MT1828 28 330 (3 min, 30 sec) MT3270 70 330 (3 min, 30 sec)

MT2136 36 200 (2 min) MT3855 55 330 (3 min, 30 sec)

MT3240 40 300 (3 min, 00 sec) MT3870 70 330 (3 min, 30 sec)

MT3255 55 300 (3 min, 00 sec)

Belt Length/

Distance

Minimum

Oven Entry

TABLE 4

Oven

Type

Belt Length/

Distance

Minimum

Oven Entry

MT3855

OPEN LOOP SYSTEM - TWIN BELT

To enter the calibration mode:

1. Press the ON/OFF key until OFF is displayed.

2. Press CLEAR FRONT BELT, FRONT BELT, FRONT BELT, PROG/ENTER to enter the AcĆ cess mode. The display flashes ACCESS.

3. The display reads ACTIVE BELT-?. Press front belt for Front Belt Calibration

4. The display reads FRONT-INIT-F.

Belt speed calibration:

1. The display reads BELT SIZE-?. Enter the length of the conveyor belt for your model. See TABLE 5. Press the PROG/ENTER key.

NOTE: Be certain to measure either the leadĆ

ing edge in and out or the trailing edge in and out. Do not use the leading edge in and the trailing edge out.

A.) The display reads STEP-1TIME-?. Enter

the time measured in STEP-1. Min: 0 Max: 59:59 (min:sec). Press the PROG/ ENTER key.

B.) The display reads STEP-1DIST-?. Enter

the belt length for your model. See TABLE 4. Press the PROG/ENTER key.

3. The display reads STEP-2. The controller is in Step 2 of the calibration procedure: minimum belt speed. The motor control is automatically set to its minimum output.

A.) The display reads STEP-2 TIME-?. Enter

the measured travel time for STEP-2. Min: 0 Max: 59:59 (min:sec). Press the PROG/ ENTER key.

B.) The display reads STEP-2 DIST-?. Enter

10". Press the PROG/ENTER key.

4. The display reads MIN-TM ENTRY? (the fastĆ est belt speed). Limits of this value are deterĆ mined by the Step-1 and Step-2 calibration values. See TABLE 5 for correct entry for this model. Press the PROG/ENTER key.

5. The display reads MAX-TM ENTRY? (slowest belt speed). Limits of this value are determined by the Step 1 and Step 2 calibration values. Use 1600 (16 min). Press the PROG/ENTER key.

6. The display flashes DONE and SAVE.

Repeat the procedure for the rear belt by pressing, CLEAR, REAR BELT, REAR BELT, REAR BELT, PROG/ENTER.

NOTE: During these adjustments, pressing the

Oven

Type

MT1828 28 330 (3 min, 30 sec) MT3270 70 330 (3 min, 30 sec)

MT2136 36 200 (2 min) MT3855 55 330 (3 min, 30 sec)

MT3240 40 300 (3 min, 00 sec) MT3870 70 330 (3 min, 30 sec)

MT3255 55 300 (3 min, 00 sec)

Belt Length/

Distance

Minimum

Oven Entry

TABLE 5

Oven

Type

Belt Length/

Distance

Minimum

Oven Entry

MT3855

MOTOR CONTROL BOARD ADJUSTMENT

High/low speed motor control board adjustĆ ment for 180 and 130 volt DC motors

NOTE: The motor control board is located on the

slide out control panel.

High Speed Motor Adjustment:

For closed loop systems follow Belt Speed VerificaĆ tion through STEP 5 (see page 6). For open loop systems follow Belt Speed Calibration through STEP 2 (see page 7 or 8).

1. With the motor connected (make no open cirĆ cuit voltage readings) measure the voltage at the motor leads (A1 & A2 in FIGURE 3) on the DC control board. If the voltage is not within 3 VDC of the specified voltage continue with step 3.

2. Turn the MAX trim pot counterĆclockwise to lower and clockwise to raise the voltage until it is within 3VDC of the specified voltage.

NOTE: For closed loop systems this adjustĆ

ment must be made quickly.

Low Speed Motor Adjustment:

For closed loop systems the computer automaticlĆ ly proceeds to low speed. For open loop systems continue Belt Speed Calibration through STEP 3 (see page 7 or 8).

1. With the motor connected (make no open cirĆ cuit voltage readings) measure the voltage at the motor leads on the DC control board (A1 & A2 in FIGURE 3). If the voltage is not 26VDC +/Ć 1 VDC, continue with step 3.

COMPUTERIZED OVENS

130 Volt System 180 Volt System

Model Low High Low High

MT1828 20 130 26 180

MT2136 20 130 26 180

MT3240 20 130 26 180

MT3270 26 130 26 180

MT3855 26 130 26 180

MT3870 26 130 26 130

NONĆCOMPUTERIZED OVENS

MT2136 20 130 26 180

MT3255 26 130 26 180

MT3270 26 130 26 180

MG3270 26 130

24 VDC SYSTEM

MT1820 3.0 21

TABLE 6

2. Turn the MIN SPEED pot clockwise to lower the voltage and counterĆclockwise to raise the voltĆ age.

NOTE: If any voltage adjustments were made hit

the CLEAR key to abort the calibration mode. Reenter the calibration mode to verify that voltage is locked in.

MT3855

Acceleration Adjustment

Yellow or Violet (pin 12)

Orange or Gray (pin 10)

Blue (pin 8)

Violet

Gray

Blue

Speed Pot

NOTE: Colors may vary

between early ovens.

Line Fuse

Minimum Speed

Maximum Speed

Socket J1

TB1

ACC MAX MIN

Test

Points

L N A1 A2

TP1

TP2

Torque (current) limiting adjustment (DO NOT ADJUST)

Switches 2,4,5,6,7

TORQ

DIP Switch on

early models only

REG

Regulation Adjustment

Armature Fuse

Line Hot (VAC)

Line Neutral (VAC)

PM Motor Armature

Barrier Terminal Block TB1

Power Line and Motor Ground

REMOVE RED PLUG FROM TOP OF DC MOTOR PRIOR TO OPERATING!

Warning: Circuit components are not at ground potential! Use only a nonĆmetallic or

insulated adjustment tool. Shock hazards may occur with conducting tools!

FIGURE 3

MT3855

RERATING THE APPLIANCE

Due to the lack of oxygen at higher elevations, the unit may need to be rerated. (The orifice size may need to be adjusted to accommodate different air pressures at higher elevations.) If not rerated, inĆ complete combustion may occur releasing AldeĆ hydes and CO or Carbon Monoxide. Any of these

are unacceptable and may be hazardous to the health of the operator.

To choose the correct orifice for different altitudes several factors must be known:

1. Altitude

2. BTUs per burner

3. Manifold pressure

4. Correct orifice size at sea level

5. BTU value of the gas

The following are generally accepted heating values:

A.) Natural Gas - 1000 BTU/Cu Ft

B.) Propane - 2550 BTU/Cu Ft

C.) Butane - 3000 BTU/Cu Ft

6. Specific gravity

The following are generally accepted values (Air = 1.0):

A.) Natural Gas - 0.63

B.) Propane - 1.50

C.) Butane - 2.00

NOTE: For other gases contact your local gas supĆ

plier for values.

Use the following formulas to calculate the correct orifice:

Firing rate

1. # of burners

BTU per burner

2. Heating value of Gas

CuFt/Hr

3. Specific Gravity Multiplier

4. Use TABLE FĆ1 from the National Fuel Gas

Code Handbook to determine the proper oriĆ fice size at sea level.

NOTE: The sea level orifice size is needed to

determine the proper orifice at any elevation.

5. Use TABLE FĆ4 from the National Fuel Gas

Code Handbook to determine the correct oriĆ fice for the applicable elevation.

6. Use TABLE FĆ3 from the National Fuel Gas

Code Handbook to determine the specific gravity multiplier.

EXAMPLE

Known factors:

1. Altitude = 5000 ft.

2. BTUs per appliance = 55,000

3. Number of burners = 2

4. BTU value of the gas = 900

5. Specific gravity = .50

Calculations:

=ąBTU per burner

=ąCuFt/hr

=ąEquiv. CuFt/h

55,000

1. 2

27,500

2. 900

30.55

1.10

Using the tables in the National Fuel Gas Code Handbook we can determine that:

1. Correct orifice size at sea level = #40

2. Correct orifice size at 5000 ft = #42

=ą27,500 BTU per burner

=ą30.55 CuFt/hr

=ą27.77 Equiv. CuFt/hr

MT3855

CHECKING THE FIRING RATE

Method #1

1. Turn off all other appliances on the line. Press the ON/OFF key on the unit to call for heat.

2. Using either the 1/2 cu. ft. or the 2 cu. ft. dials, note the time it takes the indicator to complete one revolution. See FIGURE 4.

3. Use the following formula to determine the firĆ ing rate of the meter.

3600 x size of test dial x 1000

=ĂBTU/burner

# of seconds per revolution

Example:

A.) 3600 x 2 = 7200

7200

B.)

=Ă120 Cu. Ft./Hr

C.) To convert to BTU/Hr, multiply by one of the

following generally accepted heating valĆ ues:

Natural Gas - 1000 x 120 = 120,000 BTU Propane - 2550 x 120 = 306,000 BTU Butane - 3000 x 120 = 360,000 BTU

NOTE: You may also use TABLE XII from the

National Fuel Gas Code Handbook to determine the firing rate of the apĆ pliance.

Locate the time observed in STEP 2. Move across the table to either the 1/2 cu. ft. or the 2 cu. ft. column to find the gas input to the burner.

FOOT

HALF

100 THOUSAND 10 THOUSAND 1 THOUSAND1 MILLION

TWO

FEET

CUBIC FEET

TYPICAL DOMESTIC GAS METER INDEX

FIGURE 4

Method #2

You may also determine the firing rate by sizing the main burner orifice and measuring manifold gas pressure. Either way is accurate, however method #1 is faster.

MT3855

This page intentionally left blank.

CHAPTER 5

TROUBLESHOOTING

MT3855

DC DRIVE SYSTEM

POSSIBLE CAUSE(S) SUGGESTED REMEDY

Symptom #1 - Conveyor Belt will not run

 Oven in OFF mode.

 Loose computer controller cord connection.

 Time not programmed into computer.

 Turn to ON position.

 Adjust and retighten cables and set screws.

 Program in a cook time. See page 2 of the OperaĆ

tion section.

 Emergency stop switch on OFF.

 Control circuit breaker tripped.

 Belt hooked on something in oven.

 5 amp line fuse blown.

 200 milliamp armiture fuse blown.

 Hall Effect Pickup not connected. (Closed loop

systems only)

 Pull switch out to ON.

 Reset breaker.

 Turn oven OFF, unhook and repair problem.

 Replace fuse. Determine amp draw.

 Verify the unit is set for a single pulse pickup. If

not, reset for a single pulse pickup. If yes reattach the pickup.

 Motor brushes worn out.

 Defective conveyor drive motor.

 Defective conveyor drive motor controller.

 Wire from pickup open or misplaced.

 Replace brushes.

 Replace conveyor drive motor.

 Replace conveyor drive motor controller.

 Repair or replace wire.

Symptom #2 - Computer error code MOTOR Ć SPEED Ć ERROR

 Belt speed needs calibration.  See Calibration section page 6.

 Voltage from Bodine controller to DAC not presĆ

ent. The DAC (Digital Analog Control) is a nonĆreĆ pairable component of the computer. There should be approximately 20 VDC between the red and green wires on the 3 pin connection of the DC drive board.

 DAC voltage is present but not regulated beĆ

tween 4.7 and .47 VDC when different times are programmed into the cooking computer. MeaĆ sure the voltage between the green and blue wires of the 3 pin connection.

 Replace the drive motor controller.

 Replace the computer.

MT3855

COMPUTER CONTROL SYSTEM

POSSIBLE CAUSE(S) SUGGESTED REMEDY

Symptom #1 - Computer controller displays: PROBE Ć OPEN Ć PROBE Ć SHORT and

alarm buzzer sounds

 Internal problem with computer controller.

 Verify display integ. in the 2nd level programĆ

ming. If the controller has been programmed the computer may need to be replaced.

 Loose connections at computer controller.

 Shorted or open RTD probe.

 Tighten connections.

 Use the chart on page 6-10 of the Technical ApĆ

pendix to determine if probe is bad. Replace if necessary.

Symptom #2 - Computer controller displays: ERROR Ć HIGH Ć TEMP Ć LIMIT

 Actual temperature exceeds programmed limit

 Faulty burner valve relay. Replace relay.

value. Default 605F (319C).

 Internal problem with computer controller.

 Verify display integ. in the 2nd level programĆ

ming. If the controller has been programmed the computer may need to be replaced.

MT3855

HEATING SYSTEM

POSSIBLE CAUSE(S) SUGGESTED REMEDY

Symptom #1 - Burner will not fire

 Oven in OFF mode.

 Emergency stop switch on OFF.

 Control circuit breaker tripped.

 Combustion motor not running.

 Main Temperature Controller not set above ambiĆ

ent temperature.

 Manual gas valve closed.

 Intermittent Ignition Device (IID) system locked

out.

 Air pressure switch may be open.

 Blower motor(s) not running.

 High Limit control tripped.

 Turn to ON position.

 Pull switch out to ON.

 Reset breaker.

 Check transformer for primary and secondary

voltage.

 Check main control and burner valve relays to

see if closed.

 Check relay in combustion burner box. If bad reĆ

place relay.

 Set to desired temperature.

 Open valve.

 Reference Technical Appendix pages 6-1

through 6-3.

 Check convection blower (or 3 convection fans)

for proper operation.

 Verify voltage to motor. If voltage is present, reĆ

place the motor or start capacitor.

 Verify that 625F (330C) high limit is proĆ

grammed into the controller. If so reset the high limit. Set the computer to 500F (260C). Use a pyrometer to verify the oven temperature. If the oven climbs significantly above the setpoint, use the chart on page 6-10 of the Technical AppenĆ dix to check the probe. If the probe is alright the computer may need replacement.

 Thermal switch in control compartment tripped.

 Excessive intake air temperature.

 If pilot fails to go out when the unit is shut down,

the solenoid valve is bad.

 Check hood system.

 Replace valve.

MT3855

POSSIBLE CAUSE(S) SUGGESTED REMEDY

Symptom #2 - Oven will not reach desired temperature

 Gas pressure to oven is too low.

 Top air plates missing.

 Faulty RTD probe.

 Blower motor(s) running backward.

 Controller out of calibration.

 Excessive food/debris accumulation blocking

the airflow.

Symptom #3 - Burner operates sporadically

 Air pressure switch may be open.

 Contact local gas representatives.

 Install air plates.

 Use the chart on page 6-10 of the Technical ApĆ

pendix to determine if probe is bad. Replace if necessary.

 Verify voltage to motor. If voltage is present, reĆ

place the motor or start capacitor.

 Recalibrate the controller. See Calibration secĆ

tion page 5.

 The inside of the oven should be cleaned to reĆ

move any materials that could have dropped off the conveyor belt and possibly blocked some of the air flow holes. This would include the removal of the conveyor belt, conveyor belt supports, and the nozzles. The oven interior and all parts reĆ moved should then be cleaned with an appropriĆ ate oven cleaner safe for aluminum.

 Check convection blower (or 3 convection fans)

for proper operation.

 Thermal switch tripped.

 Faulty RTD probe.

 Excessive food/debris accumulation blocking

the airflow.

 Determine the ambient temperature in the conĆ

trol compartment. If above 140F (60C) check the cooling fan operation.

 Use the chart on page 6-10 of the Technical ApĆ

pendix to determine if probe is bad. Replace if necessary.

 The inside of the oven should be cleaned to reĆ

MT3855

CONVECTION SYSTEM

POSSIBLE CAUSE(S) SUGGESTED REMEDY

Symptom #1 - Blower motor(s) not running

 Oven in OFF mode.

 Emergency stop switch on OFF.

 No power to oven.

 Motor circuit breaker tripped.

 Faulty start capacitor.

 Motor(s) burnt out.

 Motor contactor open.

 Thermal overload tripped.

 Press ON/OFF key.

 Pull switch out to ON.

 Verify power to motor(s). If there is voltage presĆ

ent, replace the motor. If voltage is not present, check the motor contactor.

 Replace fuse. Determine amp draw.

 Replace capacitor.

 Check draw (3amps or greater).

 Check that the computer is turned on and that a

cook time and temperature have been proĆ grammed. Check for voltage to the coil of the moĆ tor contactor. If voltage is present, replace the contactor. If voltage is not present, check that the blower relay is closed. If not, check for voltage at the blower relay coil. If a 12 VDC voltage is presĆ ent at the coil the blower relay is bad. If there is no voltage present at the coil the computer may need to be replaced.

 Determine if the cooling blower (or fans) are operĆ

ating. If not, verify voltage to the cooling blower. If voltage is present, replace the cooling blower motor. If voltage is not present, verify voltage through the thermal switch. If no voltage is presĆ ent, replace the thermal switch.

Symptom #2 - Blower motor(s) do not shut off

 Faulty motor contactor.

 Faulty blower motor relay.

 Faulty auxiliary contact.

 Faulty probe.

 Faulty computer.

 Replace contactor.

 If the temperature probe is good check for voltĆ

age at the coil of the blower relay. If voltage is not present the relay is bad. Replace the blower relay.

 Replace auxiliary contactor.

 Check the resistance values of the temperature

probe for values from 135Ć170F (57Ć77C). RefĆ erence TABLE 6 on page 6-10 of the Technical Appendix. If the values do not agree with the chart change the probe.

 If voltage is present at the blower relay, the comĆ

puter is bad. Replace the computer.

MT3855

POSSIBLE CAUSE(S) SUGGESTED REMEDY

Symptom #3 - Hood system does not operate when oven is on

 Fan exhaust/supply problem.

 Defective interlock circuit.

Symptom #4 - Blower motor running backward

 Motor off by thermal overload (other fans forcing

blower to spin).

 Faulty capacitor.

 Contact HVAC service.

 Replace auxiliary contactor.

 Determine if the cooling blower (or fans) are operĆ

 Replace capacitor.

MT3855

This page intentionally left blank.

CHAPTER 6

TECHNICAL APPENDIX

MT3855

INTERMITTENT IGNITION SYSTEM

PRINCIPLES OF OPERATION

Pilot flame sensing is a very important aspect of the ignition controls operation. Three zones are needĆ ed to give the proper airĆgas ratio to produce a blue pilot flame.

Zone 1 - an inner cone that will not burn because excess fuel is present.

Zone 2 - around the inner, fuel rich cone is a blue envelope. This zone contains a mixture of vapor from the fuel rich inner cone and the secondary or surrounding air. This is where combustion occurs, and is the area of highest importance for proper flame sensor location.

Zone 3 - Outside the blue envelope is third zone that contains an excessive quantity of air.

FLAME RECTIFICATION

To identify a current conducted by the flame, we use flame rectification. Place two probes in Zone 2 of the pilot flame. When the surface area of one probe is larger than the other, current tends to flow more in one direction. DC current flows in only one direction, as opposed to AC current, which alterĆ nates its direction. The current is rectified from AC to DC by increasing the surface area of one probe and decreasing the surface area of the other.

In the IID system the probes exposed to the pilot flame are the Flame Sensor and the Pilot Burner Hood. Since the surface area of the pilot hood is larger than the flame sensor, the current rectificaĆ tion process takes place. Current is conducted from terminal 4 at the control through the flame sensor cable to the flame sensor. As the current is conducted through the flame to the pilot hood, it is rectified from AC to DC because of the difference in surface area. The pilot hood is grounded back to the control, thereby completing the circuit.

Flame Sensing Circuit Current

For the ignition control to function properly, a miniĆ mum amount of current must flow through the flame sensing circuit.

As the pilot flame is established and current begins flowing in the flame sensing circuit, the current enĆ ergizes a relay. A minimum amount of current is reĆ quired to pullĆin the relay. When the relay pulls in, one set of contacts opens which shuts off the high energy spark. Another set of contacts closes, puttĆ ing 24 volts on terminal 3 which opens the main gas valve.

Current vs. Voltage

In normal operation an AC voltage will be present from terminal 4 to ground and a current will be present in the flame sensing circuit.

Current

AC Voltage

Positive Probe

FIGURE 1

DC Current

Current

AC Voltage

Transformer

Flame

Negative Probe

Ground

Even though an AC voltage is present, flame rectifiĆ cation occurs and a DC current flows in the sensing circuit.

For service checkout purposes, measuring these voltages and currents can provide useful informaĆ tion regarding the integrity of the ignition control.

Measuring the current flow rather than voltage is the preferred procedure. Due to the internal circuitĆ ry of the ignition control and varying input impedĆ ance of voltmeters, the measured voltage will vary depending on type and model of voltmeter being used. However, measuring the current provides a more precise evaluation of the ignition control and flame sensing circuit.

A proper reading not only indicates a functional control, but also verifies all components of the cirĆ cuit such as flame sensor, cable and ground.

MT3855

SERVICE PROCEDURES

Service the IID system as follows:

1. Make certain the thermostat contacts are open.

2. Check for proper supply voltage at primary and secondary of system transformer.

3. Close thermostat contacts and observe sysĆ tem.

4. Determine which system condition exists:

A.) No spark, system does not function

B.) Spark present but pilot will not light

C.) Pilot lights but main valve will not open

5. Follow the appropriate service checkout proĆ cedure to troubleshoot and repair system.

6. Observe the system through several complete operating cycles.

VOLTAGE AND CURRENT MEASUREMENTS

When servicing the electronic ignition control there are several times when voltages and currents must be measured or observed.

NOTE: All voltages measured will be AC voltage

and all current measured will be DC curĆ rent.

Terminal Terminal Use

1 Pilot valve connection between terĆ

minal #1 and ground

2 Wire from thermostat

3 Main valve connection between terĆ

minal #3 and ground

4 Flame sensor

TABLE 1

To Measure AC Voltages:

1. Set the selector switch on the voltmeter to the AC voltage position.

2. Connect the meter leads in parallel with the voltage to be measured.

To Measure DC Flame Sensing Current:

1. Turn off the power supply to the ignition conĆ trol.

2. Disconnect the flame sensor cable from termiĆ nal #4 on Johnson units or terminal #1 on LanĆ dis & Gyr units.

3. Set the selector switch on the meter to microĆ amp scale. connect the positive (red) lead to terminal #4 and the negative (black) lead to the sensor cable.

4. Disconnect the main valve lead from terminal #3. This will prevent the main burner from ignitĆ ing. A proper measurement of flame sensing current is taken with the pilot light only.

5. Turn the power back on and close the thermoĆ stat contacts. Read the current at the meter.

NOTE: The minimum current required for the

Johnson G770 is 0.15DCmA. The miniĆ mum current required for the Landis & Gyr is 2.0DCmA. (This unit is polarity specific.)

6. Turn the power off to disconnect the meter and reconnect terminal #3 and #4.

To Measure DC Flame Sensing Current Using the Johnson Y99AUĆ3 Signal Transducer:

1. Set the function selector switch to the DC voltĆ age position.

2. Turn off the supply voltage to the control.

3. Disconnect the flame sensor cable from termiĆ nal #4 on the ignition control.

4. Connect the male 1/4" spade connector (-) to the flame sensor cable. Connect the female 1/4" spade connector (+) to terminal #4.

5. Disconnect the main valve lead from terminal #3 on the ignition control.

6. Turn the supply voltage on and close the therĆ mostat contacts to cycle the system.

7. When the pilot lights, read the current on the meter display.

NOTE: The conversion factor is 1DC volt - 1

DC microamp.

3. Read the voltage at the meter.

MT3855

REPAIRING THE ELECTRONIC IGNITION SYSTEM

Flame Sensing Current Maintenance:

The flame sensor is made of carbon steel and subĆ ject to contamination and oxidation buildup. Any buildup on the sensor can add enough resistance to drop the signal below the required minimum. Carbon and oxidation can also build up on the pilot hood. The pilot hood is part of the circuit and must be kept as clean as the flame sensor.

1. Clean the flame sensor with steel wool or an emery cloth.

2. Clean the pilot hood with a small wire brush to remove any carbon or oxidation buildup.

Flame Sensor Replacement:

If the ceramic portion of the flame sensor is broken or if the contamination is extensive, the flame senĆ sor may have to be replaced.

CAUTION!

Shut off all gas to the appliance by closing the shutoff valve in the supply line to that appliance. Disconnect the power supply to prevent electrical shock or possible damage to the equipment.

1. Disconnect the sensing probe cable from the old sensing probe.

2. Remove the old sensing probe from the pilot burner.

3. Check the length of dimension B to be sure the correct replacement probe is being used. See FIGURE 2.

4. Compare the sensing probe rod lengths, diĆ mension A. If required, trim the length of the Y75 rod being installed to the same length as the sensing rod being replaced.

5. Install the Y75 sensing probe into the pilot burner. Reconnect the sensing probe cable. The connections to the sensing probe and control terminal must be secure.

6. Restore the power and the gas supply to the appliance.

7. IMPORTANT: Using a microammeter, check the signal passing through the sensing probe.

8. If the microamp signal is marginal, trim the flame sensing probe in increments of 1/8". Be sure that there is still proper flame impingeĆ ment on the flame sensing probe.

Flame must surround sensing probe tip for approximately 1/2".

9. Observe at least three complete operating cycles to see that all components are functionĆ ing correctly.

Ground Connection

Another important requirement for proper operaĆ tion is the existence of a good electrical ground beĆ tween the pilot assembly and the ignition control. This ground provides the path for sensing current to return to the control, thereby completing the sensing circuit.

In most systems we assume the pilot burner is grounded back to the control through the pilot tubĆ ing and gas valve. The gas valve would be grounded to the ignition control when the control is mounted on the valve. Controls that are not mounted to a gas valve require a separate groundĆ ing wire connecting the control to the pilot assemĆ bly.

In some instances this ground can become weak and cause a low sensing current signal. To assure that a proper ground exists between the control and pilot, a wire can be installed from one of the ground terminals to the pilot bracket. This will asĆ sure a strong ground and maintain a proper sensĆ ing current signal.

FIGURE 2

Using a 1/4" female spade connector, connect one end of the new wire to the ground strip on the igniĆ tion control. Attach the other end of the wire to a bolt or screw on the pilot burner bracket. Be sure to use a wire with a high temperature rated insulaĆ tion.

MT3855

SERVICING THE INVENT HOOD

ILLUSTRATED PARTS LIST

QTY PART DESCRIPTION (SEE FIGURE 3) ITEM

1 AMU/Exhaust Manifold/Duct Connection 1

1 AMU Duct Extension, 10 x 18 x 9"h 2

1 Exhaust Duct Extension, 9 x 18 x 12"h 3

1 AMU Support Bracket, Right 4

1 AMU Support Bracket, Left 5

1 Lower Front AMU Panel 6

1 Middle Front AMU Panel 7

1 Upper Front AMU Panel 8

2 Filter Trough/Receptacle 9

2 Filter,10x16" 10

2 Filter, 10 x 20" 11

1 Vertical Exhaust Manifold, Right 12

1 Vertical Exhaust Manifold, Left 13

1 Cooling Fan Exhaust Enclosure 14

1 Upper Exhaust Enclosure, Right 15

1 Lower Exhaust Enclosure, Right 16

1 Upper Exhaust Enclosure, Left 17

1 Lower Exhaust Enclosure, Left 18

1 Hardware Bag (includes the following)

2 Alignment Pins (qty 2)

1/4"Ć20 x 5/8" Hex Head Cap Screw (qty 4)

1/4" Flat Washer (qty 6)

1/4"Ć20 Lock Nut (qty 1)

1/4"Ć20 Shoulder Bolt (qty 1)

1/4"Ć20 x 1/2" Thumb Screw with Shoulder (qty 5)

4 Oven Securing Clip 20

TABLE 2

MT3855

FIGURE 3

CLEANING AND MAINTENANCE

CAUTION!

The oven and the ventilation system get hot during operation. Allow the oven/ ventilation system assembly to cool so as to avoid possible injury.

EVERY MONTH

1. Remove the End Enclosures (items 15-18) by lifting them up and pulling them away from the oven.

2. Remove the Filters (items 10 and 11) by lifting them up and then swinging the bottom out and down.

3. Remove the Filter Trough Receptacles (item

9).

4. Clean the parts by running them through a dishwasher or wash them by hand with hot, soapy water. Do not use scouring pads

(plastic or metal) on the exterior surfaces.

They will scratch and mar the exterior finish.

Rinse the panels in warm water and dry them.

5. Reinstall the Filter Trough/Receptacles, Filters and End Enclosures.

EVERY THREE MONTHS

1. Remove the End Enclosures (items 15-18) by lifting them up and pulling them away from the oven.

2. Remove the Filters (items 10 and 11) by lifting them up and then swinging the bottom out and down.

3. Remove the Filter Trough Receptacles (item

9).

4. Lift off the Cooling Fan Exhaust Enclosure (item 14).

5. Remove the Vertical Exhaust Manifolds (items 12 and 13) by removing the thumb screws.

6. Clean the parts by running them through a dishwasher or wash them by hand with hot, soapy water. Do not use scouring pads

(plastic or metal) on the exterior surfaces. They will scratch and mar the exterior finish.

MT3855

Wipe out the exhaust channel portion of the AMU/Exhaust Manifold/Duct Connection (item

1) assembly. Brush and clean the guards of the oven cooling fans.

7. Dry the parts and return them to their positions.

NOTE: This regular maintenance is in addition to

the daily, quarterly, semiĆannual and annual cleaning schedule included in the oven opĆ erating manual.

Exhaust Duct

AMU Duct

Clamping Collar

SERVICING ACCESS

For servicing the oven, disconnect the gas and electric services from the oven. Use the following procedure to move the oven/ventilation system asĆ sembly for maintenance.

1. Release the overĆcenter latches on the exhaust and Air MakeĆUp duct collars.

2. Slide the clamping collars up and secure them out of the way.

3. Release the brakes on the front locking casters of the oven assembly.

4. Roll the oven out away from the wall. (See FIGURE 4).

Clamping Collars

OverĆCenter Latches

Exhaust

Supply

AIR REQUIREMENTS

Duct Size CFM Static Pressure

9" x 18"

(22.9 x 45.7 cm)

10" x 18"

(25.4 x 45.7 cm)

1600

1.10" W.C. (.274 kPa)

1200

0.09" W.C.(.022 kPa)

FIGURE 4

MT3855

PRESSURE CONVERSION

PRESSURE CONVERSION CHART

in/H2O P.S.I in/Hg mm/H2O mm/Hg kg/cm

1 .0361 .0735 25.41 1.868 .0025 .0025 2.489 248.9 .2489

2 .0722 .1470 50.81 3.736 .0051 .0050 4.978 497.8 .4978

3 .1083 .2205 76.22 5.604 .0076 .0075 7.467 746.7 .7467

4 .1444 .2940 101.62 7.472 .0102 .0099 9.956 995.6 .9956

5 .1804 .3673 127.0 9.335 .0127 .0124 12.44 1244 1.244

6 .2165 .4408 152.4 11.203 .0152 .0149 14.93 1493 1.493

7 .2526 .5143 177.8 13.072 .0178 .0174 17.42 1742 1.742

8 .2887 .5878 203.2 14.940 .0203 .0199 19.90 1990 1.990

9 .3248 .6613 228.6 16.808 .0228 .0224 22.39 2239 2.239

10 .3609 .7348 254.0 18.676 .0254 .0249 24.88 2488 2.488

11 .3970 .8083 279.4 20.544 .0279 .0274 27.37 2737 2.737

12 .4331 .8818 304.8 22.412 .0304 .0299 29.86 2986 2.986

13 .4692 .9553 330.2 24.280 .0330 .0324 32.35 3235 3.235

14 .5053 1.029 355.6 26.148 .0355 .0348 34.84 3484 3.484

bar mbar Pa kPa

15 .5414 1.102 381.0 28.016 .0381 .0373 37.33 3733 3.733

16 .5774 1.176 406.4 29.879 .0406 .0398 39.81 3981 3.981

17 .6136 1.249 431.8 31.752 .0431 .0423 42.31 4231 4.231

18 .6496 1.322 457.2 33.616 .0457 .0448 44.79 4479 4.479

19 .6857 1.396 482.6 35.484 .0482 .0473 47.28 4728 4.728

20 .7218 1.470 508.0 37.352 .0507 .0498 49.77 4977 4.977

21 .7579 1.543 533.4 39.22 .0533 .0523 52.26 5226 5.226

22 .7940 1.616 558.8 41.09 .0558 .0547 54.74 5474 5.474

23 .8301 1.690 584.2 42.96 .0584 .0572 57.23 5723 5.723

24 .8662 1.764 609.6 44.82 .0609 .0597 59.72 5972 5.972

25 .9023 1.837 635.0 46.69 .0634 .0622 62.21 6221 6.221

26 .9384 1.910 660.4 48.56 .0660 .0647 64.70 6470 6.470

27 .9745 1.984 685.8 50.43 .0685 .0672 67.19 6719 6.719

28 1.010 2.056 710.8 52.26 .0710 .0696 69.64 6964 6.964

MT3855

in/H2O kPaPambarbarkg/cm

29 1.047 2.132 736.8 54.18 .0736 .0722 72.19 7219 7.219

30 1.083 2.205 762.2 56.04 .0761 .0747 74.67 7467 7.467

31 1.119 2.278 787.5 57.91 .0787 .0772 77.15 7715 7.715

32 1.155 2.352 812.8 59.77 .0812 .0796 79.63 7963 7.963

33 1.191 2.425 838.2 61.63 .0837 .0821 82.12 8212 8.212

34 1.227 2.498 863.5 63.49 .0862 .0846 84.60 8460 8.460

35 1.263 2.571 888.9 65.36 .0888 .0871 87.08 8708 8.708

36 1.299 2.645 914.2 67.22 .0913 .0896 89.56 8956 8.956

37 1.335 2.718 939.5 69.08 .0938 .0920 92.04 9204 9.204

38 1.371 2.791 964.9 70.95 .0964 .0945 94.53 9453 9.453

39 1.408 2.867 990.9 72.86 .0990 .0971 97.08 9708 9.708

40 1.444 2.940 1016 74.72 .1015 .0996 99.56 9956 9.956

41 1.480 3.013 1042 76.59 .1040 .1020 102.0 10204 10.20

mm/Hgmm/H2Oin/HgP.S.I

42 1.516 3.086 1067 78.45 .1066 .1045 104.5 10452 10.45

43 1.552 3.160 1092 80.31 .1091 .1070 107.0 10701 10.70

44 1.588 3.233 1118 82.18 .1116 .1095 109.5 10949 10.95

45 1.624 3.306 1143 84.04 .1142 .1120 112.0 11197 11.20

46 1.660 3.378 1168 85.90 .1167 .1144 114.5 11445 11.44

47 1.696 3.453 1194 87.76 .1192 .1169 116.9 11694 11.69

48 1.732 3.526 1219 89.63 .1218 .1194 119.4 11942 11.94

49 1.768 3.600 1244 91.49 .1243 .1219 121.9 12190 12.19

50 1.804 3.673 1270 93.35 .1268 .1244 124.4 12438 12.44

51 1.841 3.748 1296 95.27 .1294 .1269 126.9 12693 12.69

52 1.877 3.822 1321 97.13 .1320 .1294 129.4 12941 12.94

53 1.913 3.895 1346 98.99 .1345 .1319 131.9 13190 13.19

54 1.949 3.968 1372 100.8 .1370 .1344 134.4 13438 13.44

55 1.985 4.041 1397 102.7 .1395 .1369 136.9 13686 13.69

56 2.021 4.115 1422 104.6 .1421 .1393 139.3 13934 13.93

TABLE 3

MT3855

CONVERSION FACTORS

COMMON CONVERSION FACTORS

Multiply By To Get

BTU/hr .001054804 MJ/hr

.0002931 kW

.29285 W

BTU/Ft

.0372589 MJ/m

8.905102 kcal/m

MJ/hr 948.0434279 BTU/hr

Mj/m

26,839225 BTU/ft

kW 3414.71732 BTU/hr

.02832 m

.09290304 m

inches 25.40005 mm

feet .3048 meters

PRESSURE CONVERSIONS FACTORS

Multiply By To Get

in/H2O 0.0361 P.S.I.

25.41 mm/H2O

1.868 mm/Hg

.0025 kg/cm

.0025 bar

2.489 mbar

248.9 Pa

.2489 kPa

P.S.I 27.71 in. H2O

2.036 in. Hg

703.1 mm/H2O

51.75 mm/Hg

meters 3.281 feet

pounds .4536 kg

inches W.C. .249082 kPa

2.49082 mbar

kPa 4.01885 inches W.C.

10 mbar

mbar 0.401474 inches W.C.

kW 3.6 Mj/hr

kcal/m

Kwh/m

.1122952 BTU/ft

96.65 BTU/ft

TABLE 4

.0703 kg/cm

.0689 bar

68.95 mbar

6895 Pa

6.895 kPa

TABLE 5

MT3855

COOKING COMPUTER - TEMPERATURE VS RESISTANCE

T/F Res/Ohms T/F Res/Ohms T/F Res/Ohms T/F Res/Ohms

70 541.12 230 711.43 390 877.15 550 1038.293

75 546.51 235 716.68 395 882.26 555 1043.255

80 551.9 240 721.92 400 887.36 560 1048.212

85 557.28 245 727.16 405 892.46 565 1053.165

90 562.66 250 732.4 410 897.55 570 1058.113

95 568.04 255 737.63 415 902.63 575 1063.057

100 573.4 260 742.85 420 907.72 580 1067.997

105 578.77 265 748.05 425 912.8 585 1072.931

110 584.13 270 753.29 430 917.87 590 1077.862

115 589.48 275 758.5 435 922.94 600 1087.709

120 594.84 280 763.71 440 928.002 605 1092.626

125 600.18 285 768.91 445 933.062 610 1097.539

130 605.53 290 774.11 450 938.118 615 1102.447

135 610.86 295 779.31 455 943.17 620 1107.35

140 616.2 300 784.5 460 948.216 625 1112.249

145 621.52 305 789.68 465 953.259 630 1117.1

150 626.85 310 794.87 470 958.296 635 1122

155 632.17 315 800.04 475 963.33 640 1126.9

160 637.48 320 805.21 480 968.359 645 1131.8

165 642.8 325 810.38 485 973.383 650 1136.7

170 648.1 330 815.54 490 978.403 655 1141.6

175 653.4 335 820.7 495 983.419 660 1146.4

180 658.7 340 825.86 500 988.43 665 1151.3

185 663.99 345 831.01 505 993.436 670 1156.1

190 669.28 350 836.15 510 998.438 675 1161

195 674.57 355 841.29 515 1003.436 680 1165.8

200 679.85 360 846.43 520 1008.429 685 1170.7

205 685.12 365 851.56 525 1013.417 690 1175.5

210 690.39 370 856.69 530 1018.402 695 1180.4

215 695.66 375 861.81 535 1023.381 700 1185.2

220 700.92 380 866.93 540 1028.356

225 706.18 385 872.04 545 1033.327

TABLE 6

Blodgett MT3855G Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual