Vulcan Materials VSX24E, VSX36G, VSX36R, VSX24G, VSX42GT User Manual

...

SERVICE MANUAL

VSX BOILER BASE SERIES

CONVECTION STEAMERS

(GAS, ELECTRIC, DIRECT AND REGENERATED)

VSX24G ML-52163 VSX24D ML-52827 VSX36G ML-52360 VSX36D ML-52830 VSX42GT ML-52376 VSX42DT ML-52834 VSX24E ML-52164 VSX36R ML-52831 VSX36E ML-52829 VSX42RT ML-52835 VSX42ET ML-52833

VSX24G SHOWN

This Manual is prepared for the use of trained Vulcan Service Technicians and should not be used by those not properly qu alif ied. If yo u have attend ed a Vulcan Service School for this product, you may be qualified to perform all the procedures described in this man ual.

Thi s manu al i s no t i nten ded to be al l en comp assi ng . I f you have not atte nded a Vulca n Servic e School f or this produc t, you should read, in its entirety, the repair procedure you wish to perform to determine if you have the necessary tools, instruments and skills required to perform the procedure. Procedures for which you do not have th e n ecessary too ls, in strument s and skills should be performed b y a trained Vu lcan Service Technician.

Reproduction or other use of this Manual, without the express written consent of Vulcan, is prohibited.

- NOTICE -

A product of VULCAN-HART LO UISVILLE, KY 40201-0696 Form 24627 ( 12/98)

VSX SERIES STEAMERS

TABLE OF CONTENTS

GENERAL............................................................................. 4

Introduction ........................................................................ 4

Compartment Pan Capacity ........................................................ 4

Model Designations .............................................................. 4

Specifications ...................................................................... 5

Gas Steamers .................................................................. 5

Electric Steamers................................................................ 5

Steam Supply ................................................................... 5

Water Supply ................................................................... 6

Tools ............................................................................. 6

Water Conditi oning .................................................................. 6

STEAMER OPERATION.................................................................. 7

Cabinet Base Boilers ................................................................. 7

Gas Powered Steam Boiler ........................................................ 7

Electrically Powered Steam Boiler ................................................... 8

Direct Steam Powered Cooker ...................................................... 8

Regenerated Steam Powered Boiler .................................................. 8

Boiler Blowdown and Steamer Shut off ................................................... 8

Cooking Compartment Controls......................................................... 9

COMPONENT FUNCTION AND LO CA TION ................................................. 10

Cabinet Base Boiler Controls .......................................................... 10

Cooking Compartment Controls........................................................ 14

SERVICE PRO CE DURE S ................................................................ 15

Cabinet Bases ..................................................................... 15

Boiler ........................................................................ 15

Descaler...................................................................... 16

Water Level Controls

(Low Level Cut-Off and Different ial) ............................................. 16

Water Level Gauge Assembly ..................................................... 17

Pressure Switches (Gas and Electric Models) .......................................... 17

High Limit Thermostat ........................................................... 18

Removing The Boiler Assembly .................................................... 18

Fill and Cold W ater Solenoid Valv es ................................................ 18

Water Not Being Supplied to Boiler ................................................. 19

Blowdown Solenoid Valve Does Not Drain ............................................ 19

Steamer A chieves Pressure Slower Than Normal ...................................... 20

Inlet Water Strainer ............................................................. 21

Gas Models ................................................................... 21

Pilot , Thermoc ouple or Main Burner s ............................................ 21

Automatic Ignition Systems.................................................... 22

Gas Combination Control Valve Replacement ..................................... 23

Manifold Pressure Adjustment ................................................. 23

Electric Models ................................................................. 24

Magnetic Cont actor .......................................................... 24

Heating Element............................................................ 24

Direct Steam Models ............................................................ 26

Regenerated Steam Models (Steam Coil) ............................................. 26

COOKING COMPARTMENT.......................................................... 26

Controls ...................................................................... 26

Steam Supply Solenoid .......................................................... 26

Water Accumulating in Compartment................................................ 27

Cooking Cycl e Cannot Be Activated ................................................. 27

Intake Shut-Off Valve Adjustment (Steam Flow)........................................ 27

Door......................................................................... 27

Page 2 of 80

VSX SERIES STEAMERS

ELECTRICAL OPERATION .............................................................. 30

Water Level Controls................................................................ 30

Solid State -

Low level Cut-Off & Differential Control .......................................... 30

Electro Mechanical - Low level Cut-Off & Differential Contr ol .............................. 32

Sequence of O per ation .............................................................. 34

Gas Models ................................................................... 34

Electric Models ................................................................. 37

Schematics, Gas Steamers, Boiler Controls

VSX24G, 36G and 42GT ......................................................... 41

Manual Igni tion, St andar d Controls .............................................. 41

Electronic Ignition, Standar d Controls ............................................ 42

Manual Igni tion, CSD-1 Code Cont r ols ........................................... 43

Electronic Ignit ion, CSD-1 Code Controls ......................................... 44

Wiring Diagrams, Gas Steamers, Boil er Controls

VSX24G, 36G AND 42GT ........................................................ 46

Manual Igni tion, St andar d Controls .............................................. 46

Electronic Ignition, Standar d Controls ............................................ 48

Manual Igni tion, CSD-1 Code Cont r ols ........................................... 50

Electronic Ignit ion, CSD-1 Code Controls ......................................... 52

Schematics, Electric Steamers, Boiler Controls

VSX24E, 36E AND 42ET ......................................................... 54

Auto Blowdown, Standard Controls .............................................. 54

Auto Blowdown, Cal-Code Controls .............................................. 55

Auto Blowdown, Standard Controls .............................................. 56

Auto Blowdown, Cal-Code Controls .............................................. 57

Wiring Diagrams, Elec tric Steamers, Boiler Controls

VSX24E, 36E AND 42ET ......................................................... 58

Auto Blowdown, Standard Controls .............................................. 58

Auto Blowdown, Cal-Code Controls .............................................. 60

Auto Blowdown, Standard Controls .............................................. 62

Auto Blowdown, Step Down Transformer, S tandard Controls .......................... 64

Auto Blowdown, Step Down Transformer, Cal-Code Controls (2 contactors) ............... 66

Auto Blowdown, Step Down Transformer, Cal-Code Controls (4 contactors) ............... 68

Wiring Diagr ams, Electric Heater Circuits

VSX24E, 36E AND 42ET ......................................................... 70

Schematic, Direct Steamers, Cabinet Base

VSX24D, 36D and 42DT .......................................................... 73

Wiring Diagram, Direct Steamers, Cabinet Base

VSX24D, 36D and 42DT .......................................................... 73

Wiring Diagrams, Regenerated Steamers, Boi ler Controls

VSX36R and 42RT (Older Models) .................................................. 74

Schematic All Models - Compart ment Controls ............................................ 76

Wiring Diagram, All Models - Compartment Controls ........................................ 77

TROUBLESHOOTING .................................................................. 78

Page 3 of 80

VSX SERIES STEAMERS - GENERAL

GENERAL

INTRODUCTION

General

This manual is applic able for all models listed on the cover page. A conv ection steam er on a 42 inch base with a til ting kettle is pictur ed below for reference.

VSX42RT SHOWN

Steam Cooking

Pressure-less steamers offer an ef ficient way to produce many foods in smal l portions or l ar ger batches. Pressure-less, convecti on steam cooking will steam cook fresh foods or will steam defrost and cook froz en foods providing the maxi mum color, flavor and nutr itional value with the least expendit ur e of energy and l abor . The pressure-less steaming compartment allows the operator to open and close the door, anyti me during a cooking cycle. The steam supply will shut off when the door is opened, then re-start when the door is closed.

Compartment P an Capacity

NUMBER OF

PANS PER

COMPARTMENT

24.0

DEPTH

(INCHES)

Boiler Code Descriptio ns

Vulcan-Hart incorporates redundant c ontrols in compliance with California Code (Cal-Code) and CSD-1 as an option on steam equipment when required by stat e and/or local building code requirements. Descriptions of the codes are listed below.

Cal-Code Construct ion electrical safety circuits that, i f tri pped, must manually be reset after the condit ion causing the trip subsides. These controls consist of - (1) dual function water level cycling and low level cut off control and ( 1) si ngle funct ion low water level cut- off control ( A ux - LLCO) and a hi gh pr essure rel ief switch in conj unc tion with a m ec hanical pressure relief valve.

CSD-1 Constructi on electrical safety circuits that, i f tri pped, must manually be reset after the condit ion causing the trip subsides. These controls consist of - (1) dual function water level cycling and low level cut off control and ( 1) si ngle funct ion low water level cut-off control ( LLCO) and a high pressure reli ef switch in conjunction with a mechanical pressure relief valve. Additi onally, both circui ts have individual indicator lights that will illum inate for a visual verification of the shutdown mode.

Cal-Code and CSD-1 constr uc tion both requi r e operator intervention in the event of a shutdown. CSD-1 is mor e informative by using indicator lights to show which safety system was shutdown.

Model Desi gnations

S X XX X X

- Redundant controls in the

T - Tilting kettle (24 qt.) found on 42" wide cabinet base onl y .

Heating System: G - Gas

E - Electric D - Direct R - Regenerated

Cabinet Base Width ( inches) Pressure-less Steamer Vulcan

32.5

61.0

Pan Size 12" x 20"

Page 4 of 80

Gas Steamers

VSX SERIES STEAMERS - GENERAL

SPECIFICATIONS

INPUT

(BTU/HR)

MODEL NAT. PROP. NAT. PROP. RECOMMEND MIN RECOMMEND MIN

VSX24G 200,000 200,000 4.0 10.0 7.0 5.0 11.0 11.0

VSX36G

VSX42GT

200,000 200,000 4.0 10.0 7.0 5.0 11.0 11.0 240,000 240,000 4.0 10.0 7.0 5.0 11.0 11.0 200,000 200,000 4.0 10.0 7.0 5.0 11.0 11.0 240,000 240,000 4.0 10.0 7.0 5.0 11.0 11.0

MANIFOLD

PRESSURE

(INCHES W.C.)

NATURAL PROPANE

LINE PRESSURE

(INCHES W.C.)

Electric Steamers

AMPERAGE

1 PHASE 3 PHASE 3 PHASE - 4 WIRE

MODEL

VSX24E 24* 116 100 67 58 29 34

VSX36E

VSX42ET

*std

TOTAL

208V 240V 208V 240V 480V 220/380V & 240/415V

24* 67 58 29 34 36 100 87 44 50 42 117 48 116 58 67 24* 67 58 29 34 36 100 87 44 50

MAX

14.0

LOAD (WATTS)

360 3.0

AMPS (MAX)

120V 60HZ

Steam Supply

Dry steam must be prov ided to the steam er . If t he steam is heavy with condensate, a Ball Fl oat Trap must be used in the line and plumbed in before the pr essure reducing valve. To ensure rapid heat up of heavy c old loads, the steam supply line must be si z ed to maint ain pressure as outlined bel ow.

DIRECT STEAM

STEAMERS (POTABLE)

Supply Pressure 15 psi (max.) 15 psi (max.)

Flow Rate 100 lb. per hour total

Pre ssure Reducing

Valve Output

*Potable stea m is no t required for regenerated models but could be used.

(min.)

10 psi (furnished) set accordingly for good

REGENERA TED STEAM

STEAMERS

(*NON-POTABLE)

125 lb. per hour total

(min.)

steam gene ration but no higher than 15 psi. (furnished)

Page 5 of 80

VSX SERIES STEAMERS - OPERATION

Water Supply

Supply pressure should be 20-80 psig In line strainer f or suppl y line (Not Supplied) Supply connection cold Total dissolved solids (TDS)* less than 60 ppm Total alkalinity less than 20 ppm Silica less than 13 ppm Chloride less than 30 ppm PH fact or 7 to 8

(*17.1 ppm = 1 grain of har dness)

TOOLS

Standard

Standard set of hand tools.



Volt-Ohm-Meter (VOM) with AC current tester.



(Any quality VOM wit h a sensit ivity of at least

20,000 ohms per volt c an be used)

Gas leak checking equipment.



Gas Pressure Manometer



Special

CLR Treatm ent Kit - Used to remov e



Calcium/Lime/Rust fr om a boiler ( Contact

Vulcan Authorized Service Cent er s ).

Adaptor to test thermocouple closed circuit



voltages (DC) on gas models with manual

ignition (purchase locally).

NOTE:

An exam ple of one adaptor type is pict ur ed

below.

Adaptors v ary between manuf ac turers.

WATER CONDITIONING

Furnishing the boiler wit h soft water to reduce scale formation is important. Scale formation will reduce steam output, cause premature c omponent f ailure, and shorten equipm ent life. Most water supplies contain scal e pr oduc ing miner als such as Calcium and Magnesium. A s steam is generated, the minerals remain and dissolve into the water. As the concentration of these minerals inc r eases past a certain point, they pr ec ipitate from the water and coat the inside of the boiler, heating elements, thermostat bulbs and water level probes. Because of the high temperature of these surfaces, the precipitated minerals bake onto them and become very difficult to remove.

This causes several problems:

1. Reduce the heat transfer efficiency of the heating system .

2. Cause premature failure of E lectric heaters.

3. Water l evel pr obes will give false readings.

4. Thermostat bulbs will sense temperature incorrectly.

These problem s are common to any manufacturer's steamer regardless of design, but t hey c an all be prevented by furnishing the boiler with soft water. Vulcan recommends the water cont ain less than 60ppm of “ total dissolved soli ds” (TDS) and hav e a PH fact or between 7 to 8. These water properties can be achieved by using a properly maintained water softener.

Other chemical pr oper ties in water supplies can also affect good steam generation and vary fr om within each state and locality.

The water level probes in the boiler use ions i n the water to detect the water level. demineralized or de-ionized water since it is "non conductive" and the water level can not be detect ed.

Do not use

fully

NOTE:

remove mi nerals from the water. Vulcan recommends that a local water treatment

specialist be consulted before t he installat ion of any steam generating equipment.

Steamers that operate over a long peri od of time without the benefit of a water softener, which have developed a heavy scale build up, should be cleaned bef or e using a water softener.

Page 6 of 80

The use of strainers, or filters will not

VSX SERIES STEAMERS - OPERATION

STEAMER OPERATION

WARNING:

SERVICING THE STEAMER. THE COOKING COMPARTMENT CONTAINS LIVE STEAM. STAY CLEAR WHEN OPENING EACH DOOR.

Ensure that all utility connections to the steamer have been made and are turned on.

On model s that are Cal-Code/CS D- 1 equipped, amber col ored lights for Hi pressure and low water level will illuminate and stay on until the boiler is full and the manual reset switch pressed.

Gas Powered Steam Boiler

1. Open the cabinet door and turn main power

THE STEAMER AND ITS PARTS ARE HOT. USE CARE WHEN OPERATING, CLEANING OR

On Models with Automatic Ignition

CABINET BASE BOILERS

switch ON. The red light will illuminate, water will begin filling the boiler and the blowdown solenoid valve will close. The boiler should fill, in four to eleven minut es. Observe water l evel gauge glass to verify that water is in boi ler and that the l evel in the gauge glass is about hal f full. Both valves on gauge glass assembly m ust be open to fill the gauge. Older models equipped with a manual “ball” type blowdown valve must be closed for the boiler to fill. The cycling pressure switch will maintain the proper steam pressure in the boiler by cyc ling the heating system on and off to generate steam pressure.

On Models with Manual Ignition

knob on the gas combination contr ol valve has three positions (O n- P ilot-O ff) for control of main burners and pilot. Turn knob on gas combination valve to PILOT then depress and light pilot burner with a lit taper. Maintain knob in depressed position for about 30 seconds and release. Observe that pilot burner flame stays on. If the flame should go out, wai t 5 minut es before relighti ng.

- The

The knob on the gas com bination cont r ol valve has two positions (On-Off) for control of main burners and pilot. For the automatic ignition system t o work, the knob must be set i n the ON position or gas for the pilot and main burners will not flow. Also, the ignition c ontrol module ON/OFF/RESET switch must be in the ON position to operate. Thi s switch is located on the upper left side of the electrical control box for the ignition control module. A red light will illuminate when the switch is in the ON posi tion. DO NO T ATTEMPT TO MANUALLY LIGHT THE PILOT IN AN AUTOMATIC TYPE IGNITION SYST EM.

After the main power switch is turned ON and the ignition control modules RESET switch is in the ON position, sparking will begin three seconds lat er to light the standing pilot. If the pilot light s, a si gnal is sent back through the igniti on c able indicat ing the presence of pilot flame and sparking stops. If the water level i n the boiler has reached the minimum level, the burners will ignite and begin to heat t he water in the boi ler. After approximately 15 minut es, st eam should be present f or cooking product. Observe that the boi ler pressure gauge indicates steam pressure of 8-10 psi. If a pilot flame i s not established immedi ately, sparki ng will continue for 90 seconds. After that duration, the ignition control module will lock out and needs to be r eset to start the pilot and burner lighting cycle again.

Turn knob on gas combination cont r ol valv e to ON. If the water level in the boiler has reached the minimum level, burners will ignite and begin to heat the water in the boiler . After approximately 15 minutes, steam should be present for cooking product. Observe that the boiler pressure gauge indicat es steam pressure of 8-10 psi.

Page 7 of 80

VSX SERIES STEAMERS - OPERATION

Electrically Powered Steam Boiler

Open the cabinet door and turn m ain power switch ON. The red light will illuminate, water will begin filling the boiler and the blowdown solenoid val ve will close. The boiler should fill, in 4 to11 minutes. Observe water level gauge glass to v er ify t hat water is in boiler and that the level in the gauge gl ass is about half full. Both valves on gauge glass assembly m ust be open to fill the gauge. Older models equipped wi th a manual “ball” type blowdown valve must be closed for the boiler to fill. If t he water level in the boiler has reached the minimum level, the magnetic cont ac tors will close, the heaters will energize and begin to heat the water in the boiler. After approx imately 15 minutes, steam should be present for c ook ing product. O bserve that the boiler pressure gauge indicates steam pr essure of 11-13 psi.

Direct Steam Powered Cooker

1. Open the cabinet door and turn main power switch ON.

A. The red light on the switch will illuminate. B. If steam pr essure is above the m inimum

setting on the cooking compar tment pressure switch then the switch will close, ready light will come ON and power to the other controls will be supplied.

C. Observe that the steam pressure gauge in

the cabinet base, indicates 10-12 psi.

2. Steamer is ready t o c ook pr oduc t.

Regenerated Steam Powered Boiler

BOILER BLOWDOWN AND

STEAMER SHUT OF F

Turn the steamer off at least once daily and blow down the boiler t o r emov e sedi ments, scalants and lime build-up in the boil er . Always blowdown the boiler when it is under maximum pressure and no steam is bei ng used.

Automatic blowdown.

A. Newer Models

and turn main power switch OFF. The switches’ red light will go out, the blowdown/drain solenoid valve will be deenergized and the boiler will begin to drain. The cold water condenser solenoid will continue to operat e, as needed, to condense steam and to cool the water going into the drain.

B. Older Models

and depress blowdown timer butt on. Blowdown timer will operate for 4 minutes. At the end of blowdown, turn fill switch to ON and allow boi ler to f ill.

Manual blowdown.

A. All Models

blowdown valve loc ated on the bottom front of the cabi net base. After the boiler has completely drained, c lose blowdown valve and t ur n fill switch to ON and allow boiler to fill.

- Open the cabi net door

- Turn power switch OFF

- Turn power switch OFF. Open

1. Open the cabinet door and turn main power switch ON. The pilot light will illuminate, water will begin filling the boiler and the blowdown solenoid valve will close. Models equipped with a manual “ball type” blowdown valve need to be closed for the boiler to f ill. The boiler should fill, in approximately 15 minutes. Observe water level gauge glass to verify that water i s i n boiler and t hat the level i n the gauge glass is about half full.

Both valves on the gauge glass assembly must be open to fill the gauge. When the water reaches the minimum level, the steam solenoid valve will open, allowing steam to enter the steam coil in the heat exchanger tank and begin heating the water. Af ter approxi mately 20 minut es, a sufficient amount of pressuriz ed steam should be present for cooking pr oduc t.

Page 8 of 80

VSX SERIES STEAMERS - OPERATION

COOKING COMPARTMENT

CONTROLS

When the steam pressure in the c ook ing compartment manifold reaches approximately 3 psi , the cooking compartment pressure switch closes, suppling power to the ot her c ontrols. The ready lights will illuminate and after approximately one minute, the steam pressure in the boiler will reach the upper li mit of 10 psi. If the pressure drops below approximately 3 psi , the pressure switch will open, removing power f r om the cooki ng c ompartm ent controls.

NOTE:

the ready light comes on, a loud clanki ng sound wil l be heard (oil c anning) and the ready l ights will flash for several seconds. This condition is caused by the manifold pressure being on t he “fringe” of the pressure switch set point. When a cook t imer i s set, the compartment steam solenoid valve opens causing the manifold steam pressure to drop, slightly below the pressure switch set point. At the same time, steam pressure is still increasing in the boiler. This opposing condit ion causes a pressure “bounce” to occur but after the steam pressure passes approximat ely 4 psi this condition subsides. Under normal steam cycling pressures, this conditi on will not be seen.

If a cook ing timer is set immediat ely aft er

5. When timer knobs reach "0", buz z ers will sound, steam generation will cease, cooking lights will go off and ready lights will come on. To silence buz z er s, turn timer knobs to off position.

6. During a cooking cycle, the heat ing system will cycle on and off as necessary to maintain steam pressure in the boiler.

NOTE:

occur due to the r egulated constant steam supplied from the building. Steam will come on for cooking when a cook tim er is set and go off at the end of that time.

7. Turn power switch off t o r emov e power from

8. Blowdown boiler. See “BOILER BLOWDOWN

On direct st eam units, no steam cycling will

the steamer and the red light will go out.

AND STEAMER SHUT-OFF” under “STEAMER OPERATION”.

1. With both tim er knobs at the off position, open the compartment doors and observe that no steam has entered the c ook ing compart ments, then close the doors.

2. Set both tim er knobs at 2 minut es. The ready lights will go off, the cooking lights will come on, and steam will begin to enter the compartments.

3. After one minute, open each door and observe that steam has ceased to enter each compartment, cook ing light s go back to ready, and one minut e is remaining on each cook timer.

4. Close doors and steam generation and cook timing will resume. Observe the floor drain to ensure that live steam from compart ments is being cooled by cold water fr om the cold water condenser solenoid valve.

Page 9 of 80

VSX SERIES ST E A M E RS - COMPONENT FUNCTION AND LOCATION

COMPONENT FUNCTION AND LOCATION

CABINET BASE BOILER

CONTROLS

WARNING

HOT. USE CARE WHEN OPERATING, CLEANING OR SERVICING THE STEAMER. THE COOKING COMPARTMENTS CONTAIN LIVE STEAM. STAY CLEAR WHEN OPENING EACH DOOR.

Water Level Gauge Assembly

confi r mation that water level is bei ng maintained in the boiler during operati on. The correct water level is a point one-half of the height of the glass. The manual valves at the top and bottom of this assembly m ust be full y open and only closed if the glass tube is damaged.

Observe that the water is clean and clear in the glass tube. The appearance of ext r eme murkiness in the water i ndicates inadequate water quality and will cause failure of controls and the steamer. War ranty does not cover mal functi on due to poor water conditions. Blowdown and/or clean out t he boiler as outlined in “BOILER BLOWDOWN AND STEAMER SHUT-OFF” under “STEAMER OPERATION” and “BOILER” under “SERVICE PROCEDURES”.

Water Level Control and Level Sensing Probes

these controls al low water to enter the boiler to f ill and maint ain the proper water l evel. They will also shut off the heat source to the boiler i f the water level drops too low.

The water level cont r ol works by using three different probe lengths to monitor the water level. The probes consist of a high level (HL), low level (LL) and low water cut-off (LLCO). The level sensing probes may easil y be r emov ed to inspect f or lime build up. A s a rule, the condi tion of these devic es will indicate the overall water condition of t he boiler. Clean the probes if needed.

NOTE:

clogging will occur if a daily blowdown procedure is not followed.

Boiler Fill Solenoid Valve

boiler when dem anded by the water level control to maintain the correct water level in the boiler.

Cold Water Condenser Solenoid Valve

cold water flow into the boiler blowdown drain box to condense steam and cool the hot water before its discharge int o the drain.

: THE STEAMER AND ITS PARTS ARE

- permits visual

Controls m ay not function and serious

- admits water to the

- allows

Cycling P ressure Switch

between prescribed limit s by t ur ning the heat source on and off.

High Limit Pressure Sw itch

design to the cyc ling pressure switch but used as a high li mit. The pressure settings are at hi gher and lower limits than the cycli ng pressure switch in order to turn off the heat sourc e before the boi ler pressure reaches its limit and automati c ally resets af ter the pressure drops below the lower limit set point.

Blowdown/Drain Solenoid Valve

plumbed into the drai n pipe of the boiler. Newer steamer models will automatically blowdown when power is turned off by using a normally open solenoid valve. Older models can have a solenoid valve t hat is activated by depr essing a separate blowdown timer button or have a manual “ball” type valve. Daily boiler blowdown is essential to proper operation and component life by removing sediment and scalants that may be lodged in the chamber of the boiler .

Strainers

to prevent foreign matt er from becoming lodged in the fill or cold water condenser solenoid valves and to keep unwanted parti c les out of the system. A "Y" strainer should be inserted upstream of the fill solenoid valve.

On model s using a direct steam suppl y , a strainer i s used in the pressure regulating valve.

Power Switch

to the controls and the steam generat ing process is started in the boiler. The power switch is located on the front of the boiler contr ol box.

Water Inlet Valve

stop water fl ow to t he steamer when the steamer is being serv iced. Newer models will have a sm all Petcock type val ve whil e older model s will be a “ball” type valve. This valve should remain open during normal operati on.

High Limit Thermostat

shuts off the heat source if the boil er temperature exceeds a specified limit . All standard models are equipped with a surface high limit .

Descaler

boiler and is used to help control boiler surf ac e scaling. Two descalers are used in each boiler.

Handhole Cover Assembly

removed, allows internal ex amination and cleaning of boiler shell and its components if required.

- a strainer is used in the water inlet line

- when turned ON, power is suppli ed

- the water inlet v alve is used to

- hangs submerged in water i nsi de the

- control s boi ler pressure

- a switch of identical

- this valve is

- a protective device that

- when unbolted and

Page 10 of 80

VSX SERIES ST E A M E RS - COMPONENT FUNCTION AND LOCATION

Pressure Gaug e

- indicates boiler steam pressure.

Normal operating pressures are listed below.

STEAMER

TYPE

Gas 8 -10 Electric 11 - 13 Direct 10 - 12 Regenerated 10 - 12

- drains steam c ondensate and water from

Drain

PSI

cooking compartments and boiler.

Check Valve

- On models with the deli me piping assembly option, prevents the ejection of hot water and steam out of the deli me funnel if the manual delime fill valve were to be opened.

Delime Port Assembl y

- On models with the deli me piping assembly option, allows the boiler and other internal components to easily be delimed to remove calcium, lime and rust bui ld up. See ”BOILER” under “SERVICE P ROCEDURES”.

Standing Pilot (Gas Boilers)

- should always remain lit t o light the main burners upon a cal l for heat unless the steamer will not be in use for an extended period. If the pilot flame goes out, wait 5 minut es before relighting.

Main Burn ers ( Gas Boilers)

- heats the water in

the boiler to generate steam.

Combination Control Valve (Gas Boilers)

- a gas solenoid that opens t o allow gas flow when a call for heat is made and also regulates the m anifol d gas pressure.

Pressure Regul ating Valve (Direct & Regenerated Steam)

- regulates the manifold

steam pressure between 10-12 psi.

Magnetic Contactor (E lectric Boil ers)

- when coil is energized, suppl ies power to the electric heating elements.

Heating Elements (Electric Boilers)

- heats the

water in the boi ler to generate steam.

Page 11 of 80

VSX SERIES ST E A M E RS - COMPONENT FUNCTION AND LOCATION

Page 12 of 80

VSX SERIES ST E A M E RS - COMPONENT FUNCTION AND LOCATION

Page 13 of 80

VSX SERIES ST E A M E RS - COMPONENT FUNCTION AND LOCATION

COOKING COMPARTMENT

CONTROLS

WARNING:

HOT. USE CARE WHEN OPERATING, CLEANING OR SERVICING THE STEAMER. THE COOKING COMPARTMENT CONTAINS LIVE STEAM. STAY CLEAR WHEN OPENING EACH DOOR.

The upper section of the steam er c onsi sts of two separate cooking compartm ents. Each compartment functions independently with its own set of contr ols. Power is supplied to t he c ontrols only after the steam pressure rises above 3 psi to close the compartment pressure switch. The switc h remains closed as long as steam pressure stays above 3 psi but will open i f the pressure drops below that setting.

Ready Light (Green)

is ready to cook.

Cooking Light (Red)

is in a cooking cycle.

Cooking Timer

tim e between 0-60 minutes. When a timer i s set, the steam supply solenoid valve is energized to al low steam int o the cooking compartment but only after the boiler has reac hed its operating pressure. Also, energizes the buzzer when time expires.

THE STEAMER AND ITS PARTS ARE

- when lit, indicates steam er

- use to set desired cooking cycle

Steam Solenoid Valve

allow steam into the cooking compartment (normally closed v alve).

Compartment P r essure Switch

the control s only after the steam pressure rises above 2. 3 psi to close the compartment pr essure switch. The switch remains closed as long as steam pressure stays above 2.3 psi but will open if the pressure drops below that setting.

Manifold Pressure Gauge

of steam pressure in manifold. T he intake shut-off valve should be adjusted so manifold pressure remains at 9 psi with both compartments on.

Steam Supply Manifold

from the boiler for each cook ing compart ment. Supplies steam up to the steam sol enoid valve.

Intake Shut-Off Valve

from the boiler to the steam suppl y manifold. This valve should NOT be left fully OPEN to boiler steam supply. See “INTAKE SHUT-OFF VALVE ADJUSTMENT (STEAM FLOW) under “SERVICE PROCEDURES”.

- when energized, opens to

- supplies power to

- indicates the amount

- main st eam supply line

- main st eam supply shut-off

Buzzer

turned off manually.

Door Switch

timer.

- signals end of a cook cycl e, must be

- removes electr ical power to the

Page 14 of 80

VSX SERIES ST E AMER - SERVICE PROCEDURES

SERVICE PROCEDURES

WARNING:

MEASUREMENTS WHILE POWER IS APPLIED TO THE MACHINE. EXERCISE EXTREME CAUTION AT ALL TIMES. IF TEST POI NT S ARE NOT EASI LY ACCESSIBLE, DISCONNECT POWER, ATTACH TEST EQUIPMENT AND REAPPLY POWER TO TEST .

BOILER

Inspection

It is recommended that the boiler be thoroughly inspected f or excessive scale and li me build up on a quarterly basi s. In hard water areas or for units heavily used, a more frequent interval should be used. This inspection consists of an i nternal examination and cleaning of the boiler shel l, an examination and possibl e r eplacement of the descaler, a check of li me build up on the water level sensing probes, and a check of all boiler controls, including the pressure switches.

Periodic servi c e must be perfor med as outlined in these procedures. See “WATER CONDITIONING” under “GENERAL”.

WARNING

INSTRUCTI ONS ON THE CLR BO TTLE. USE PLASTIC OR RUBBER GLOVES TO AVOID SKIN CONTACT. IF CLR LIQUID COMES IN CONTA CT WIT H THE SKI N, RINSE WITH CLEAN W AT ER.

Clean-Out (All Boiler Models)

1. Turn steamer OFF and drain boiler.

2. Remove hand hol e plate and gasket (top front)

3. Remove ol d descaler retaining springs if

CERTAIN PROCEDURES IN THIS SECTION REQUIRES ELECTRICAL TEST OR

CABINET BASES

: READ AND FOLLOW THE

from the boiler by removing the nut and clamp, then tapping t he c over lightly to free i t while holding the c over stud. This prev ents the cover from dropping into boiler.

present.

NOTE:

to nine gallons for both gas and el ec tric m odels depending on the boiler size and BTU/KW rating.

NOTE:

contact wit h steamer components, lightly rinse of f with clean water.

Boiler water c apac ities vary between seven

If deliming solution acc idently comes in

A. Models with Blowdown Timer

deliming solution into boiler shell. Mix the solution in accordance with the instructions on its container. Proceed to step 9.

B. Models without Blowdown Timer

the incoming water supply. Turn the unit ON to close t he dr ain valve. Pour deliming solution into boiler shell. Mix the solution in accordance with the instruct ions on its container. Proceed to step 9.

C. Models with Del iming P ort Assembly

Before mixing and pouring del iming solution into boiler , clean the seati ng surfaces for the hand hole gasket and then install a new gasket. Position t he hand hole plate and tighten down. Turn off the incoming water supply. Tur n the unit ON to close the drain valve. Open the deliming assembly valve and pour the deliming solution into the port. Mix the solution in accordance with the instructions on its contai ner. Close the deliming assembly valve and proceed to step 10.

- Pour

- Turn off

4. With a wire brush, or equivalent, dislodge and

remove all loose scale from boiler shel l. The loose mater ial must be either scooped fr om the boiler or flushed through t he dr ain.

5. Check probe canister and f loat valve assembly

(regenerated models) for a scale build up and clean as necessary.

6. Check drain hole f or obstructions.

7. Install two new descalers.

8. Mix the deliming solution according to the

instructions for the chemical in use then add solution to boiler.

Page 15 of 80

9. Clean the seating surfac es for the hand hole gasket and then Instal l a new gasket. Position and tighten t he hand hole plate.

VSX SERIES ST E AMER - SERVICE PROCEDURES

10. Cooking c ompartm ent timers are to be in the OFF position. Turn the boiler switch ON and open water valve if necessary.

11. Boiler is to operate under pressure for 90 minut es or per the instructions for the chemical in use.

12. Drain boiler by normal methods. Refill boiler and allow heat until f ully pressurized.

13. Repeat step 12 thr ee times.

14. The steamer is now ready for nor mal operation.

Deliming Only (Models with Deli ming Port Assembly)

Boiler delim ing should be perfor med on a weekly, bi-weekly or monthly basi s, depending on the quali ty of the local water supply.

On steamers using a water purifi c ation system, follow the instructions for that system to deli me the boiler. Only use the type of chemical recommended or described in the instructions for deliming wit h this type of system.

1. Turn steamer OFF and drain boiler.

2. Mix the deliming solution according to the instructions for the chemical in use then add solution to boiler.

NOTE:

Boiler water c apac ities vary between seven to nine gallons for both gas and el ec tric m odels depending on the boiler size and BTU/KW rating.

NOTE:

If deliming solution acc idently comes in contact wit h steamer components, lightly rinse of f with clean water.

Models with Blowdown Timer

- Open the deliming assembl y valve and pour the deliming solution into the port. Mix the solution in accordance with the instructions on its contai ner. Close the deliming assembly valve and proceed to step 3.

Models without Blowdown Timer

- Turn off the incoming water supply. Turn the unit ON t o close the drain valve. Open the deliming assembly valve and pour the deliming solution into the port. Mix the solution in accordance with the instructions on its contai ner. Close the deliming assembly valve and proceed to step 3.

3. Top compartments are to be in the OFF position. Turn the boiler switch ON and open water valve if necessary.

4. Boiler is to operate under pressure for 90 minut es or per the instructions for the chemical in use.

5. Drain boiler by nor mal m ethods. Refill boiler and allow to heat up and build steam pr essure.

6. Repeat step 5 three times.

7. Unit is now ready for normal operation.

Descaler

The descaler i s accessible through the hand hole opening. It is a coiled wire wound around a solid cylindrical cor e, and hangs by an open loop from the shell's horiz ontal stay rod, about 4 inches from the front of the shell . If t he wi r e is eaten through, or if the core of the descaler is eaten away to half its original size, a new descaler should be i nstalled.

To install a new descaler, stretch its wire coil so that the descaler hangs with i ts core completely below the mi nimum water level in the boiler, but hanging free. The descaler must not contact the bottom of the boiler shell, elec tric heating element s or t he regenerating steam coil s on uni ts so equipped.

Water Level Cont rols (Low L evel Cut-Off and Different ial)

Solid State

1. Ensure that water is filling the boiler.

2. Check for correct voltage being applied to the board.

3. Verify the water level control boar d oper ation as outlined in “WATER LEVEL CONTROLS” under “ELECTRICAL OPERATION”.

A. Does the HL LED light up and the HL r elay

energize to change the contact stat e at power on?

B. As the boiler fills, does the LLCO LED light

up and the LLCO relay energize to change the contact state after the water level reaches the LLCO probe?

Page 16 of 80

VSX SERIES ST E AMER - SERVICE PROCEDURES

C. Does the HL LED go out and the HL relay

de-energize, allowing the cont ac t state to switch back to i ts starting condition after the water level reaches the HL pr obe?

4. If water is in t he boiler but is not being detected by the water level probes, the probes may need cleaned and/or boiler delimed. See “BOILER”.

5. After checking the abov e items, if the water level control board does not appear to be functioning as outlined, then repl ac e the board.

6. Check unit for proper operation.

Electro Mech anical WARNING:

DISCONNECT THE ELECTRICAL POWER TO T HE MACHINE AT THE MAIN CIRCUIT BO X. P LA CE A TAG ON THE CI RCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.

Loose electri c al connections may prev ent the heat from coming on or may cause the boiler to overfill. Accumulation of boiler scale on or near the sensing probes may cause them to retain water on the insulator surface. This may prevent the boiler from filling or cause dry firing. Dry firing will result in damage to heating elements or to the boiler. Verify the water level cont r ols operation as outlined in “WATER LEVEL CONTROLS” under “ELECTRICAL OPERATION”.

With the individual probe l ead wir e r emov ed, check the probes and contactor s as outl ined below:

1. With an ohmmeter , check the probe bet ween

the wire connection and shell. An open c ircuit should be present when the boiler is empty. If resistance is present, r emov e and c lean the probes. Also check for a cracked insulator, then reinstall probes and check. When the boiler is full of water, a resistance reading should be measurable bet ween the probes and shell only.

NOTE:

Actual resistance reading will depend on

water qualit y and pr obe c ondition.

2. Check low level and dif ferenti al water level

controls. Wi th the power switch ON, use a voltmeter to check the i nput voltage across terminals 1 & 2. Meter shoul d r ead 115V . With the boiler empty, ac r oss terminals 9 & 10, y ou should read 300 to 350V. If you do not r ead this voltage, then coil is bad and contac tor should be replaced.

3. Remove sensing probe. First rem ove the

bolted cover over the sensor cluster. Then remove the wire from the pr obe and unscrew the probe with a wrench. Be c ar eful to note the locati on of each probe and the number of the wire connected to it. Incor r ec tly connected wires will cause the controls to malfunction.

4. Clean probe thoroughly, r emov ing ALL deposits from the insulat or . Do not use an abrasiv e on the insulator; use a soft cl oth.

5. Inspect through the probe socket for the presence of water. Water must drain from the probe housing. If in doubt, pour water into the housing and observe that it drains quickly. If the housing fails to drai n, remove the housing or housing cover and clean the interior mechanically.

Water Level Gauge Assembly

Close the valve at the top and at the bottom of the gauge assembly. Unscrew the packing nuts at the top and bottom of the glass tube. Slide the glass tube upwards, until the bottom of the tube is clear of the fitting and lift it out.

When r einstalling the tube, use new sealing washers. Do not over t ighten the packing nuts; it could break the gauge glass. Check that both top and bottom valves are f ully open.

Pressure Swit ches (Gas and E lectric Models) WARNING:

DISCONNECT THE ELECTRICAL POWER TO T HE MACHINE AT THE MAIN CIRCUIT BO X. P LA CE A TAG ON THE CI RCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.

Remove the boil er control box cov er to access the two controls. T he pr essure switch on the left is the cycling or prim ar y c ontrol; the one on the right i s the high li mit c ontrol. They ar e identical switches, differing only in their settings.

Turn the power ON and l et the boiler c ome up to pressure. Aft er the ready light comes ON, t ur n one of the cook ing compartment timers on to exhaust steam f rom the boi ler. Observe boiler pr essure gauge readings for sev eral cycles and compare them with the pressure settings in the chart. If the readings differ, adjust the pressure settings as described below.

Two slotted and square headed adjustment screws extend thr ough the top of t he swit c h c ase with dials and pointers to indicate the appr oxim ate setting. The adjustment screw directl y above the dial changes both the cut-out (off) and the cut-in (on) points. Set it first to give the proper off setting. Turning the scr ew cl oc k wise i ncreases the pressure. Then set the second adjustment screw to give the proper on setting. The pressure settings for eac h switch are li sted below.

PRESSURE SETTINGS (PSI)

CYCLING HIGH LI MIT

UNIT ON OFF ON OFF

Gas 8 10 6 15

Electric 11 13 6 15

Page 17 of 80

VSX SERIES ST E AMER - SERVICE PROCEDURES

High Limit Thermostat WARNING:

DISCONNECT THE ELECTRICAL POWER TO T HE MACHINE AT THE MAIN CIRCUIT BO X. P LA CE A TAG ON THE CI RCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.

Remove thermostat (bi-metallic disk type) and inspect f lat surfac e of thermostat for c or r osi on or rust. Replace if rusted.

Clean thermostat mount ing and thermostat surfaces before remounting or r eplacing. A good metal -to-met al contact is essential for pr oper functioning of the thermostat. This service m ust be performed at least once a y ear .

On gas boilers, the high li mit t her mostat is loc ated on the face of the boiler close to t he si ght glass on the right side. For access, remove t he small metal cover placed ov er the therm ostat.

On electr ic boil er s, the high li mit t her mostat is located behi nd the contactor box cover. On elec tric boilers with two heating elem ents, the therm ostat is connected to one of the heating element lugs. On electric boiler s with four heati ng elements, t he thermostat is located bet ween the center pair of element s at the top of t he elements.

Removing The Boi ler Assembly WARNING:

DISCONNECT THE ELECTRICAL POWER TO T HE MACHINE AT THE MAIN CIRCUIT BO X. P LA CE A TAG ON THE CI RCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.

WARNING:

SHUT OFF THE GAS BEFORE SERVICING THE UNIT.

WARNING:

ALL GAS JOINTS DISTURBED DURING SERVI CING MUST BE CHECK E D FOR LEAKS. CHECK WITH A SOAP AND WATER SOLUTION (BUBBLES). DO NOT USE AN OPEN FLAME.

A. CHECK ALL JOINTS PRIOR TO THE

GAS VALVE (SOLENOID) BEFORE LIGHTING UNIT.

B. CHECK ALL JOINTS BEYOND GAS

VALVE (SOLENOID) AFTER UNIT IS LIT.

Blow down the boiler and

Newer Steamer Mod els

allow to cool, if necessary. Ensure that all utilities to the steamer are off. Drain any ex cess water from the boiler . Disconnect the steam supply line, power leads and drain l ines from the cooking compartment top to the boi ler base. Remove the cooking compartment top by unscrewing the bolts holdi ng the cooking compartment top to the boiler base. The bolts are loc ated behind the small louvered access panels on the left and right side of the steamer. Lift the top of f the boiler base and place to t he si de.

Remove the remaining plumbing and elec trical connections from the boiler to t he c ontrols. Remove the bolts securi ng the boiler t o the frame and lift it out. Reverse procedure to i nstall a new boiler.

Older Steamer M odels

- Blow down the boiler and allow to cool, if necessary. Turn off all utilities to the steamer and di sconnect supply lines. Dr ain any excess water from the boiler. Remove the screws holding any control box that would obstruct removal of the boiler through the front of the base.

Disconnect the 1/4 inch diameter water inlet tubing. Disconnect the wir e and c onduit fr om the low water cut-of f probes, high limit thermostat, and the automatic blowdown valve (if so equipped). Uncouple the uni on on the steam outlet and blow down the lines.

Remove all t he scr ews holdi ng the flue and flue collector to the base. Remove t he anc hor screws holding the boiler to the frame. Sli de the boiler forward. T he bur ner box, anchored onl y by the boiler, must be prevented fr om slidi ng forward with the boiler .

Fill and Cold Water Solenoid Valves WARNING:

DISCONNECT THE ELECTRICAL POWER TO T HE MACHINE AT THE MAIN CIRCUIT BO X. P LA CE A TAG ON THE CI RCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.

Removal

1. Turn off the water supply to the steamer.

2. Open the base doors and remov e the two

screws from the top of the boiler control box.

3. Pull the quick connect power leads off the

solenoid valve being serviced.

4. Disconnect the water li nes for the valve being

servi ced and remove the valve from the unit.

5. Reverse procedure to install.

Disassembly NOTE:

It is recommended that the v alve be removed from the unit for cl eaning to prevent damage to the lines and fittings when the stem is removed from the body.

1. Remove the c oil assembly from the valve stem

by lifting up on t he retaining c ap at the top of the solenoid valve and sliding the met al cov er plate off.

2. Clamp the body of the v alve in a vise.

3. Mark a scribe line on the stem nut to the valve

body for proper retightening.

Page 18 of 80

VSX SERIES ST E AMER - SERVICE PROCEDURES

4. Remove the stem locking nut to remove t he stem f rom the valve body.

5. All parts are now accessible for inspecti on and cleaning.

NOTE:

If internal solenoid parts appear to be damaged or worn, then r eplace the solenoid valve. Do not reuse damaged or worn parts. No internal solenoid parts are available as a service replacement. Pay careful attention to proper orientation and placement of parts during reassembly.

A. Check rubber seal on bottom of plunger . B. Check plunger spring. C. Check O-ring in valve body. D. Check ports in valve body.

6. Reverse procedure to install.

Water Not Being Supplied to Boiler

Turn the steamer on. Check that water suppl y is available to the steamer. A fter approximately 10 minut es, if no water is observed in t he water level gauge sight glass, then chec k for a problem with the water solenoid valve or water level cont r ol probe.

WARNING:

DISCONNECT THE ELECTRICAL POWER TO T HE MACHINE AT THE MAIN CIRCUIT BO X. P LA CE A TAG ON THE CI RCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.

Scalants may be cov er ing the water level cont r ol probe giving a f alse indicat ion of a suf ficient water level in the boiler. Detach, remove and thoroughly clean the water level probe and canister assembl y to remove scalant s and l ime build up. This condition indicat es extremely poor water quali ty being supplied to the boiler and/or boiler cl ean out/and deliming has not been performed. T he water conditi on must be cleared up imm ediately wit h a proper water condit ioner to avoid f ur ther problem s with the steam er . Replace the water l evel pr obes and canister assembl y . Perform a boiler c lean-out and deliming procedure. S ee “BOILER”.

Water may be draining through an open boiler blowdown solenoid v alve as qui c k ly as it’s fed to the boiler. Loose wiring, a burned out coil or particles of scale trapped i n the valve seat may prevent the valve from closing.

Newer steamer models use a plunger type rod that raises and lowers to permit steam/water flow out of boiler. If debris has accumulated around the water orif ice, the plunger may not seat pr oper ly to close off the opening. I f this symptom i s suspect, remov e the solenoid as outlined in “FILL AND COLD WATER SOLENOID VALVES”. Remove any debris found on seali ng surfaces, reassemble and install. If the solenoid valve still does not function properl y , replace it with a new valve and chec k for proper operation.

Older steamer model s have a movable blade and when closed, the blade reac ts as a guillotine that should be free t o move fully down into the valve pocket (projection at bottom of valve) so that the pierced hole in the blade aligns perfectly with the body opening. If debris has accumulated in the bottom of the valve pocket, then the blade will not move into the pocket completely. If this symptom is suspect, remove the solenoid as outlined i n “FILL AND COLD WATER SOLENOID VALVES”.

NOTE:

On this valve body, remove t he two assembly bolts holding the brass body together and remove the loose i nternal parts. Remove any debr is found on seali ng surfaces, reassemble and install. If the solenoid valve still does not func tion properly , replace it with a new valve and chec k for proper operation.

Blowdown Solenoid Valve Does Not Drain

If your steamer has an automatic blowdown drain valve.

Older Models

- when the blowdown timer button is pressed, the boiler blowdown valve opens. If y our steamer has a manual blowdown drain v alve, close the v alve.

Newer Models

- are equipped with nor mally open solenoid valves that close when energized by the main power switch. When the main power switch is turned off, the solenoid valve is de-energized and the boiler blowdown valve re-opens.

The water contai ned in the boil er , being under pressure, should be blown through this valve and be noticeabl y visible exhausting out the steam er dr ain.

If t he blowdown operation appears to func tion sluggishly or not at all, considerable scalants may be lodged in the dr ain pipe and/or the valve. Disconnect the valve f rom the drain line and i nspect both the valve and the drain pipe fixed to the boi ler. If consi derable scalants or l ime build up is apparent, then not only the valve, but also the boiler and water level control must be thoroughly cleaned. S ee “FILL AND COLD WATER SOLENOID VALVES” for a cleaning procedure of a solenoid valve and "BOILER” for a cleaning proc edur e of the boiler.

Page 19 of 80

VSX SERIES ST E AMER - SERVICE PROCEDURES

Steamer Achieves Pressure Sl ower Th an Normal

If t he boiler requires more than 15 minutes (20 minut es for regenerated models) to achi eve normal operating pressure as li sted in below, then check the following conditions.

NORMAL OPERATING

STEAM PRESSURES

UNIT RANGE (PSI)

Gas 8 - 10

Electric 11 - 13

Direct 10 - 12

Regenerated 10 - 12

All Models (With Boiler)

A. A heavy bui ld-up of scal ants has possibly

coated the interior of the boil er . The insulating eff ect of the scalants hampers heat transfer. Unbolt and remov e the hand hole cover plate and gasket assembly. Exam ine interior of boiler and if scalants and/or li me buil d up is apparent, perform a boiler clean-out and deliming pr oc edur e. See “BOILER”. If consi der able scalants are evident, then bot h the boiler blowdown solenoid valve and the water level control must also be examined.

Gas Model s

A. Low incoming gas pressure causes

reduced BTU output . Check incoming line and manifold gas pressures as outlined i n “MANIFOLD PRESSURE ADJUSTMENT.”

B. Gas combination control valve

malfunction. Check incoming and manifol d gas pressures as outlined in “MANIFOLD PRESSURE ADJUSTMENT.” If pressure adjustment s are made and mani fold pressure remains low, replace the combination valve and test unit for proper operation.

C. Gas burner ports clogged or obstruction

around air shutter . After a per iod of time, gas burners can accumul ate carbon in their ports or become clogged by food and grease debris from kitc hen c leaning, restrict ing performance. To clean burners, remove them from burner box and boil in water for 10 -15 minutes to dislodge clog. Clean-out any remaining debris from the gas ports using a wire brush, scribe or pic type met al instrument. Remove any other forei gn objects that appear to be obstructing the gas ports or air shutters.

D. Gas orifice clogged or obstructed around

air shutter. It is possible for debris to become lodged in the smal l gas orifice opening over time. Clean-out the gas orif ice using a round m etal instrument of the same hole diameter or sl ightly sm aller. Clean as needed. If clogging r eappear s, the orifice should be remov ed, cleaned and reinstalled. Remove any other foreign objects that appear to be obstructi ng the gas orifice or air shutt er s.

Electric Mo dels

A. Heavy scale build up on heating element

causes reduced heating.

B. One or more elec tric heating element s

malfunctioning.

C. One or m or e magnetic c ontactors not

pulli ng in, to power heati ng elements.

D. If unit operates under three phase power,

then one of t he phases m ight be lost.

Direct Steam Models

A. Building steam supply pressure low. B. Cooking compart ment steam sol enoid

valve malf unc tion.

C. Steam pr essure regulator adjusted too

low.

D. Clogging in the steam line reduces steam

supply.

Regenerated (S t eam Coil) Steamers

A. Heavy scale build up inside copper steam

coil. B. Building steam supply pressure low C. Cooking compartment steam solenoid

valve malf unc tion.

Page 20 of 80

VSX SERIES ST E AMER - SERVICE PROCEDURES

Inlet Water Strainer

The in-line Y strainer shoul d be located upstream of the fill valve solenoid. Unscrew the cap f r om the body on the leg of the Y that shoul d be pointing downwards toward the floor. Remove the screen and any foreign particles trapped in the opening. Rinse the screen thoroughly to remove accumulated debris and replace the screen in the valve body. If screen can not be thoroughly cleaned, replace it with a new one. Reinstall the cap and ensure that the Y strainer is positioned with t he c ap pointing downward to catch debris.

The pressure regulating valve strainer will become clogged if dirty steam lines are connected to dir ec t steam models. Remove the hex nut on the bottom of the pressure regulating valve to clean the strainer and valve seat.

GAS MODELS

Pilot, Thermocouple or Main Burners WARNING:

POWER TO T HE MACHINE AT THE MAIN CIRCUIT BO X. P LA CE A TAG ON THE CI RCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.

DISCONNECT THE ELECTRICAL

NOTE:

settings are m ade, always replace the adj ustment cover scr ew to assure proper gas control operation.

If adjustments in gas or pilot pressure

WARNING:

SERVICING THE UNIT. The pilot thermoc ouple supplies a millivolt signal

(DC) to an int ernal solenoid valve on the gas combination control valve when heated. This solenoid valve is designed to shut off the gas flow to the pilot and main bur ner s i n c ase of a malfuncti on in the system . When ener gized by the thermocouple voltage, the valve is held in the open positi on to permit gas flow. The pilot burner flame is controlled by an adjustable needle valve located under a small cap screw on the combi nation control valve.

When experiencing nuisance pil ot outages, v isually check pilot flame for the proper contact on thermocouple and the flame color. Also, chec k to see that unusually str ong floor drafts are not interfering with pr oper heating of the thermocouple by the pil ot flame.

The pilot flame should be a steady blue flame that envelopes the thermoc ouple tip. The flame should be about one inch l ong wi th half its length extending beyond the outer edges of the pilot shield. If the pilot flame does not appear to be this length and color , then an adjustment is necessary. See the diagram below for an example of un satisf ac tory pilot flames. Turn cloc k wise to dec r ease pi lot flame and counterclockwise to increase.

SHUT OFF THE GAS BEFORE

If adjustment does not resul t in a pil ot flame of proper size, t hen gas might not be flowing properly to the pilot. Check for a plugged pi lot orifice, a kinked or plugged pilot gas supply tube and for l ow gas supply pressure. The pil ot operates unregulated at gas supply pressures while the pressure regulat or in the combination control valve regulat es pressure to the main burners only. V isually check the thermocouple tip (hot end) and tube lead for kinks or pinches that might be causing a short between the tube and the wire i nsi de. Also, check t he threaded connector tip for cor r osi on, tarnish or dir t which can cause a poor connection. If t he thermocoupl e shows either of these signs, it shoul d be r eplaced with a new one.

NOTE:

thermocouple tip t o the control valve is an elec trical connection and must be clean. Do not use any sealing compound on the threads or over tight en the threaded connection. Finger tighten the nut plus 1/4 turn with a wrench. O ver tightening the nut could crush the insulat or , shorting the ther mocouple.

If t he pilot flame is correct and ther e ar e no dr afts, then the problem is in t he thermocoupl e output voltage or the gas solenoid valve in the combination control.

The connecti on of the tubing from the

Page 21 of 80

VSX SERIES ST E AMER - SERVICE PROCEDURES

Check the thermocouple output voltage (DC millivolts) with a VOM. If a meter is not available, replace the t hermocouple with a new one and recheck operation. Fir st, take a closed ci r c uit reading (adaptor r equired) with the pilot on. Next, take an open circuit readi ng by disconnecting the thermocouple tube from the valve and connecting meter leads to the tube and threaded end. Manually press and hold down OFF/PI LOT/ON knob and light the pilot. All ow the pilot to heat the therm oc ouple for one to two minutes and compare the readings with the chart bel ow.

THERMOCOUPLE

READINGS

CLOSED CIRCUIT

Typical 15

Range 10 - 20 20 - 35

OPEN

CIRCUIT

If either of the readings is less than the minimum or thermocouple is not operating as described, replac e the therm ocouple. To replace, rem ove the pilot assembly by di sconnecting thermocouple and pilot gas supply tubing from the c ombination control valve and remov e the two screws holding the pil ot to its brack et. Replace the thermocoupl e or pilot assembly and check for proper operat ion. If after replacing thermocouple, the pilot or main burners are still not functioning properly, then a problem in the gas combination control valve exists as well. Replace the combination control valve as outlined in “GAS COMBINATION CONTROL VALVE REPLACEMENT” then check for pr oper oper ation.

NOTE:

Gas combination control valves are not servi ceable and should not be di sassembl ed. Once you have isolated the problem to t his control, replace it. Do not attempt to repair the assembly.

The mai n burners are lanced port steel burners (5 or 7 burners, depending on the unit) and have adjustable air shutters. Fi xed orifice type hoods are used to establish the gas flow to each burner. Set each burner air shutter opening just large enough to eliminate any yellow tip i n the burner flame.

To remove main burners, lift burner and sl ide it to the rear just enough to clear the gas ori fice hood. Lower the front end of burner and bri ng it for ward under the manifold pipe. When reinstal ling burners, ensure that locating pin i s i n the hole for pr oper positioning and to prevent burner f r om roll ing over .

Automatic Ignitio n Systems

When the main power switch is turned ON and the ignition control modules reset switch is i n the ON position, the ignit ion control module is energized with 24 v olts between terminals five and six.

High voltage is sent from t er minal nine to the spark electrode and an out put of 24 volts i s sent from terminals two and three to the pilot coil in the combination valve, allowi ng gas to flow to the pilot. The sparking will continue for 90 seconds or until the flame sensor has confi r med that an adequate pilot flame is present.

Once the pilot flame is confirmed, a 24 volt output from terminal one will be sent, allowing the cycling coil of the com bination valve to operat e at the request of the cycl ing pressure switch.

Terminals:

1. Main Voltage

- 24V AC will be present on terminal #1 with the pilot sensing elec trode sensing an adequate pilot fam e. This output will remain present as long as the pilot flame remains adequat e.

2. Common (MV/P V ).

3. Pilot Voltage

- 24V AC will be present on terminal #3 at the instant an input voltage is supplied to the module. This voltage will remain present on terminal #3 providing an adequate pilot flame is established within 90 seconds. In the event that an adequate pilot flame is not establ ished within 90 seconds this output voltage will drop out.

4. Ground (burner).

5. Ground (24VAC Neutral) .

6. 24V AC Input.

7. High Voltage to spark el ectrode (The pi lot flame current is sensed by the Ignitor Module via the spark elect r ode high voltage wire and terminal #9).

Page 22 of 80

VSX SERIES ST E AMER - SERVICE PROCEDURES

Spark Ignition Control Test

1. If the ignition contr ol modul e does not appear to be sparking to ignite gas, perform t he following checks.

A. Check to ensure that all electrical terminal

connections on the igniti on c ontrol module and the ignitor are clean and t ight.

B. Verify that the ignition contr ol module and

the ignitor have good ground wire connections. The ignitor mounting brac k et should have good metal t o metal c ontact to its m ounting surfac e.

C. Turn the main power switch ON. Turn the

ignition control modules re-set switch OFF then ON.

D. Check f or 24V A C output on the ignition

control module transformer.

1) If 24VAC is present then replace ignition control module and re-t est.

2) If 24VAC is not present t hen ensure that transformer is receiving 120VAC input. I f igni tion control module transformer is recei ving pr oper voltage, then replace ignition control module t ransformer and r e- test.

2. If the ignition contr ol modul e and transform er are funct ioning properly, then check the following ignitor conditions.

A. The gap between the spark probe and the

ground clip should be approximately 1/8 inch. If the gap appears to be excessive or poor sparking is occur r ing, remove the electronic ignition pil ot and adjust gap.

C. Check the i gnition cable for tightness or

damaged insulation.

3. Check unit for proper operation.

Gas Combination Co ntrol Valve Replacement WARNING:

DISCONNECT THE ELECTRICAL POWER TO T HE MACHINE AT THE MAIN CIRCUIT BO X. P LA CE A TAG ON THE CI RCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.

WARNING:

SHUT OFF THE GAS SUPPLY BEFORE SERVICING THE UNIT.

WARNING:

ALL GAS JOINTS DISTURBED DURING SERVI CING MUST BE CHECK E D FOR LEAKS. CHECK WITH A SOAP AND WATER SOLUTION (BUBBLES). DO NOT USE AN OPEN FLAME.

A. CHECK ALL JOINTS PRIOR TO THE

GAS VALVE (SOLENOID) BEFORE LIGHTING UNIT.

B. CHECK ALL JOINTS BEYOND GAS

VALVE (SOLENOID) AFTER UNIT IS LIT.

NOTE:

Gas combination control valves are not servi ceable and should not be di sassembl ed. Once the problem has been isolated to t his control, replace it. Do not attempt to repair the assembly.

Remove the two screws on the control box cov er . Disconnect electrical supply wires and conduit running to the c ombination control valve. Disconnect the thermocoupl e lead and pilot gas supply tube f rom control and pipe connections on each side of t he control. Reverse procedure t o install and check unit for proper operat ion.

Manifold Pressure Adju st ment

B. Inspect the ceramic flame rod insul ator for

cracks or evidence of exposure to ex treme heat, which can permit leakage to ground. If either of these conditions exist, then replace the pilot i gnitor assembly.

Page 23 of 80

WARNING:

DISCONNECT THE ELECTRICAL POWER TO T HE MACHINE AT THE MAIN CIRCUIT BO X. P LA CE A TAG ON THE CI RCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.

WARNING:

SHUT OFF THE GAS SUPPLY BEFORE SERVICING THE UNIT.

1. Open the front cabinet doors and turn the Gas

Combinat ion Control Valve OFF.

2. To measure the manifold pr essure, remov e the

1/8 inch NPT plug (pressure tap) on the outlet side of the valve and attach a manometer .

3. Turn the gas combinat ion control valve and the

main power switch to ON.

4. Observe the m anometer pressure reading and

compare to the pressure chart near the end of this procedure.

VSX SERIES ST E AMER - SERVICE PROCEDURES

A. If other appliances are connected t o the

same gas line, turn them all ON and check manometer pressure reading again. If a pressure drop of ½ inch water column or more is observed, then t he gas supply needs to be checked by the gas line installer or the local gas company for adequate sizing.

B. If no other gas appliances are connected

to the gas line and the manifold pressure still requires adjustment, proceed to step

5. Remove the adjustment screw cap to ac c ess the pressure adjustment screw.

A. To increase pressure, turn the screw

clockwise

B. To decrease pressure, turn the screw

counterclockwise

7. Once the correct pressure has been set, turn the power switch OFF, replace the adjustment screw cap and 1/8 inch NPT plug (pressure tap) on the outlet side of the valve.

8. Check unit for proper operation.

ELECTRIC MODELS

Magnetic Contactor WARNING:

POWER TO T HE MACHINE AT THE MAIN CIRCUIT BO X. P LA CE A TAG ON THE CI RCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.

The contactor can be serviced by removing t he cover of the contac tor box.

A noisy contactor (hum or chatter) is general ly due to enough dust or dirt on the armat ur e pole faces or around the armature core that the magnet coil cannot pull the armatur e into a completely sealed position. This can usually be c or r ec ted by blowing or wiping the pol e faces clean. To inspect electrical contacts, remov e c over at top of contac tor by removing two screws which hold it in place. Replace contactor if the electric al contacts appear to be pitted or burned.

DISCONNECT THE ELECTRICAL

NOTE:

Accurate gas pressure adjustments can only

be made with the gas O N and the burner lit.

6. After the burner lights, set t he pr essure as outlined below:

PRESSURE READINGS

(INCHES W.C.)

GAS TYPE MANIFOLD

Natural 4.0 7.0 5.0

Propane 10.0 11.0 11.0

RECOMMENDED MIN MAX

* If t he incomi ng line pressure is

LINE

less than

the minimum st ated, then the manifold pressure can not be set correctly.

Heating Element WARNING:

THE FOLLOWI NG ST EPS REQUIRE POW E R TO BE APPLIED TO THE UNI T DURING THE TEST. USE EXTREME CAUTION AT ALL TIMES.

1. Measure the voltage at the heating element

terminals and v er ify it against the dat a plate voltage.

A. If voltage i s corr ec t then proceed to step 2. B. If voltage i s not c or r ec t, check the

following:

1) Voltage supply to the uni t. a. Fuses or breaker blown. b. Power to contactor coils. c. Contactors not pulling in.

(Mechanical)

2. Check current draw (amps) through the heating element lead wires.

See table below for

proper values.

A. If current dr aw is corr ect then heati ng

element is ok.

B. If current dr aw is not c or rect then proceed

to step 3.

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