Victory Refrigeration VBC-70, VBC-480, VBC-350, VBC-660 User Manual

R e f r i g e r a t i o n a t i t s b e s t

Blast Chiller Operator’s Manual

Reach-In Models: VBC-35, VBC-70, VBC-75 & VBC-100 Roll-In Models: VBC-175, VBC-220, VBC-350,VBC-480 & VBC-660

Manual Part No. 50850502

Rev: 00

Print Date: 11/5/04

1 1 0 W o o d c r e s t R o a d , C h e r r y H i l l , N J 0 8 0 0 3

Phone: [phone] Fax: [phone] Website: www.victory-refrig.com

E-Mail: [e-mail] ● [e-mail] ● [e-mail]

PART OF AGA FOODSERVICE GROUP

T H A N K Y O U

Thank you for purchasing a Victory Refrigeration Reach-In or Roll-In Blast Chiller! This unit has passed our strict Quality Control Inspection and meets the high standards set by Victory Refrigeration. You have made a quality investment that with proper maintenance will give you years of service.

Please read the following installation and maintenance instructions before installing or using your unit. If you have any questions, please call our Customer Service Department at [phone].

IMPORTANT INFORMATION - PLEASE READ

●Please read these instructions carefully before installing or using. If recommended procedures are not followed, warranty claims will be denied.

●Your Warranty Registration information is located on the next page of this manual. Please complete the card and submit it to Victory Refrigeration within 10 days of installation. Failure to properly register equipment can void the warranty.

●Victory Refrigeration reserves the right to change specifications and product design without notice. Such revisions do not entitle the buyer to corresponding changes, improvements, additions or replacements for previously purchased equipment.

●A detailed Owners Manual with a troubleshooting guide, parts lists and additional information can be ordered from the factory or may be downloaded free from the website at www.victory-refrig.com.

Warranty

(Continental USA Only)

The Seller warrants to the original purchaser, equipment manufactured by Seller to be free from defects in material and workmanship for which it is responsible. The Seller's obligation under this warranty shall be limited to replacing or repairing at Seller's option, without charge, F.O.B. Sellers factory, any part found to be defective and any labor and material expense incurred by Seller in repairing or replacing such part, such warranty to be limited to a period of one year from date of purchase or thirteen months from date of shipment from Seller's factory, whichever is earlier, provided terms of payment have been fully met. All labor shall be performed during regular working hours. Overtime premium charges will be at Buyer's expense.

Proof of purchase must be supplied to Seller to validate warranty. This warranty is valid only if equipment is properly installed, started-up and inspected by the dealer or authorized Victory Service agent.

Removal or alteration of the serial/data plate from any equipment shall be deemed to release Seller from all warranty obligations or any other obligations, expressed or implied.

This warranty does not cover Thermostat or Defrost Timer calibration and/or adjustment, freight damage, normal maintenance items outlined in Owner's Manual, adjustment of door mechanisms or replacement of light bulbs, fuses or batteries.

Any repairs or replacement of defective parts shall be performed by Seller's authorized service personnel. Seller shall not be responsible for any costs incurred if the work is performed by other than Seller's authorized service personnel. Reimbursement claims for part(s) or labor service costs must be made in writing. Model, cabinet serial numbers and installation location must be shown on the claim. A receipted bill from the servicing agency must accompany the claim, together with full details of the service problems, diagnosis and work performed. Victory reserves sole discretion whether further documentation on a claim is to be submitted.

Seller shall not be liable for consequential damages of any kind which occur during the course of installation of equipment, or which result from the use or misuse by Buyer, its employees or others of the equipment supplied hereunder, and Buyer's sole and exclusive remedy against Seller for any breach of the foregoing warranty or otherwise shall be for the repair or replacement of the equipment or parts thereof affected by such breach.

The foregoing warranty shall be valid and binding upon Seller if and only if Buyer loads, operates and maintains the equipment supplied hereunder in accordance with the instruction manual provided to Buyer. Seller does not guarantee the process of manufacture by Buyer or the quality of product to be produced by the equipment supplied hereunder and Seller shall not be liable for any prospective or lost product or profits of Buyer.

THE FOREGOING WARRANTY IS EXCLUSIVE AND IN LIEU OF ALL OTHER EXPRESS AND IMPLIED WARRANTIES WHATSOEVER. SPECIFICALLY THERE ARE NO IMPLIED WARRANTIES OF MERCHANTABILITY OR OF FITNESS FOR A PARTICULAR PURPOSE.

The foregoing shall be Seller's sole and exclusive obligation and Buyer's sole and exclusive remedy for any action, whether in breach of contract or negligence. In no event shall Seller be liable for a sum in excess of the purchase price of the item.

You may register online at www.victory-refrig.com, fax this completed page to [phone], or copy and mail form below to Victory.

*NOTE: The following mail-in form or online registration must be filled out and forwarded to Victory by the installer or customer within 10 days after start-up. Failure to do this will invalidate the warranties. Retain this information for your records.

110 WOODCREST ROAD CHERRY HILL, NJ 08003-3648

TEL: [phone] ● FAX: [phone]

WARRANTIES NOT VALID UNLESS REGISTERED AT FACTORY WITHIN 10 DAYS AFTER START-UP DATE.

Cabinet Model No.______________________

Cabinet Serial No._________________

(Data plate information located inside cooler on the upper left wall)

ORIGINAL DATE OF INSTALLATION __________________________________________________________________

INSTALLATION COMPANY NAME ____________________________________________________________________

STREET_______________________________ CITY_____________________ STATE______ ZIP CODE___________

DISTRIBUTOR’S NAME_____________________________________________________________________________

STREET_______________________________ CITY_____________________ STATE______ ZIP CODE___________

		TABLE OF CONTENTS
Page 2	Receiving Shipment
	Unpacking
	Installation
	Electrical Supply
	Start-Up
	●	Main Control Breakers
	● Initial Start-Up Error Code & Checks
Page 3	Principals of Operation
	Loading and Packing
	Food Storage Time
	Operation of Blast Chillers
Page 4	Operation of Blast Chillers (continued)
	Defrost
	Roll In Blast Chillers with Storage Pod
	The Controls
Page 5	The Controls (continued)
	Programming A Blast Chill Cycle
	Alarm and Warning Levels
Page 6	Alarm and Warning Levels (continued)
	The Printer
Page 7	Printer Set Up
	Logger Paper Installation
	Print Cartridge Removal & Installation
Page 8	Power Failure
	Maintenance
	●	Cleaning
	●	Door Gasket
	●	Condenser Cleaning
Page 9	Technical Service & Replacement Parts
	Rules of Thumb
Page 10	Before Calling Service Guide (for Common Problems)
Pages 11-27	Parts Lists
Pages 2840	Wiring Diagrams

Proper installation is the first step to operation. We recommend that your refrigerator or freezer be installed by an authorized Victory Certified Installer.

RECEIVING SHIPMENT

All units are performance tested and thoroughly inspected prior to shipment. Upon leaving the factory, all units are in perfect condition. Upon receipt, examine the exterior of the shipment packaging for any signs of rough handling. If the cabinet is damaged, it should be noted on the delivery slip or bill of lading and signed. A claim must be filed immediately against the carrier indicating the extent and estimated cost of damage incurred.

UNPACKING

Remove all external and interior packing and accessories. Ensure all packaging is disposed of safely.

INSTALLATION

The cabinet should stand level to ensure correct operation of self closing doors and proper drainage of condensate from the evaporator.

Models fitted with casters are non-adjustable, therefore a level platform/floor should be provided where the cabinet is to be located. On models fitted with adjustable legs leveling may be achieved by adjustment of the bottom section of the legs. For marine specification models with flanged feet for deck fixing and bulkhead fixings, installation should be carried out by a specialist marine company.

For top mounted refrigeration systems please ensure there is 20” [500mm] between the top of the cabinet and ceiling for service technician access and ventilation.

If the cabinet has been laid on its back or tipped, DO NOT switch on immediately. Leave the cabinet in the upright position for at least 12 hours before switching on.

ELECTRICAL SUPPLY

Wiring should be done by a qualified electrician in accordance with local electrical codes. All models, with the exception of the VBC-100 and all Roll-In VBC’s, come fitted with a NEMA plug for safety and must be grounded. We recommend that if the plug or cable fail, contact Victory’s parts department for a replacement part.

The VBC-100 and Roll-In VBC’s are 3-phase and requires connection to a suitable supply.

START-UP

MAIN CONTROL BREAKERS

Should the equipment fail to run on initial connection, please check that all Main Control Breakers (MCBs) are in the "ON" position at the back of cabinet. (*Note: The "ON" position is confirmed by red indicators on the MCBs.)

INITIAL START-UP ERROR CODES & CHECKS

An “a7” error code (indicating a loss of power) with an audible alarm sound off will always occur during an initial start-up of a blast chill cabinet. Press the "CANCEL" button (red with symbol), the error code and audible alarm will discontinue.

A “Battery Failure Configuration Suspect” error message ticket will always print during an initial start-up. Do not be alarmed when the error message prints; it is only indicating that the back-up batteries that hold the cabinets data during a power failure is not fully charged. Full battery charge should be within 24 hours after start-up.

Check the time and date on the printed tickets. If the ticket has printed an incorrect time and date or the printer logger paper is not feeding properly, see page 7 for further instruction.

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PRINCIPLES OF OPERATION

Victory blast chillers have been designed to quickly reduce the temperature of food in accordance with Department of Health guidelines on the chilling of cooked foods. All operators should be conversant with Department of Health publication, Chilled and Frozen Guidelines on Cook-Chill and Cook-Freeze Catering Systems.

Fast temperature reduction is not brought about by placing the food in a very cold cabinet like a deep freeze. This would only dry the food badly and take a very long time to reduce its temperature to the required level. The secret of fast temperature reduction is in delivering the correct blast of air and ensuring correct and unobstructed horizontal air flow inside the cabinet.

This is why Victory has the option of soft and hard facility on blast chill.

Exceptions: depending on the density types and sizes of the portions the chiller might not be capable of achieving the required guidelines, therefore, the load and/or depth of the food layers should be reduced. You may find it necessary to experiment with different amounts of food and loading methods in order to achieve the optimum performance with your blast chiller.

LOADING AND PACKING

Regulations state that product should be placed in the Blast Chiller within 30 minutes from completion of cooking. The packaging of food and the way in which it is loaded or placed within the apparatus can have a significant effect on the time within which the temperature can be reduced to the required level and the amount of food which can be processed in each chilling batch.

When blast chilling always use metal or foil containers which are good conductors. Plastic or polyurethane containers insulate the food from the cold air. When chilling unportioned food we recommend the use of the appropriate pan that is at least 2-1/2” [63.5mm] in depth. Likewise, placing lids or covers on food will also increase the chilling time but may be of some use when processing some delicate foods to avoid dehydration.

Always load your machine in such a way that it is possible for the cold air to contact all sides of the containers. Avoid stacking containers directly on top of one another as this will drastically extend the chilling time and take special care not to block the air ducts.

Always load the machine before selecting the blast cycle. Unless it is unavoidable do not open the door of the machine while the blast cycle is engaged.

In the case of roll-in rack models, bumper bars are fitted to the walls inside the machine. This assists in the correct positioning of the rack(s) so as to avoid blocking the air flow.

FOOD STORAGE TIME

Chilled foods can be stored for up to 5 days at between 32°F/0°C and 38°F/+3°C.

OPERATION OF BLAST CHILLERS

Your machine has been set-up at the factory and no further adjustments should be necessary.

Note: The control systems employed are micro-processor based and contain no user serviceable components. Instructions on setting up the control panel thermostats are available from the manufacturer. These should only be reset by a qualified service technician.

Normal Storage:

This is the storage temperature at which food can be held and the Blast Chiller automatically switches into this mode at the end of each cycle.

Storage Mode

On some chillers there is more than one fan installed these may not all operate during the storage mode giving a reduced air circulation within the chiller. All other models have one or more Aerofoil fans. The unit cycles on the store thermostat, the sensor of which is placed in the air.

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Blast Chill Cycle:

All machines have the facility for the operator to use any of the 4 pre-programmed timed cycles and a probe control blast chilling cycle, with the option of soft or hard blast.

The probe controlled blast cycle functions via the food core probe supplied. The probe monitors the core temperature of the food and will not permit the blast cycle to stop until the default temperature (37°F\3°C) is reached. When controlling the cycle with the food probe make certain that the probe or probes are located in the product before the blast cycle is started.

Pressing the selections automatically adopt the previous settings on the first push. So the repeating of blast is just pushing buttons 1- 2- 3 & Blast .

Blast Chill Cycle (Hard or Soft):

During the blast chill hard cycle the air temperature inside the approximately 14°F (-10°C). This is for the timed chilling cycle only.

temperature stays above 32°F (0°C ). All blast chillers have 3 basic modes:

cabinet should go down to During soft chill cycle the air

1.Normal storage: 34°F (1°C) to 37°F (3°C)

2.Blast Chill Hard: 14°F (-10°C)

3. Blast Chill Soft:

34°F (1°C)

DEFROST

At the end of each cycle, a defrost will automatically clear any ice from the evaporator ready for the next cycle.

During the operation in storage mode a defrost will be performed automatically at the factory preset intervals of 6 hours.

Furthermore, if a blast cycle is cancelled and the defrost thermostat is measuring 34°F (+1°C) or less, the machine will automatically proceed to defrost.

When the machine is in the defrost mode the ‘Cabinet Temp’ window of the control panel will display ‘DEF’. When the defrost cycle is finished the compressor will run for approximately 90 seconds before the fans cut in.

Following every defrost period there is a 3 minute period during which a blast cycle cannot be selected. This short interval is to allow defrost water to drip away from the evaporator.

The cabinet is now ready to start another cycle if desired. During the defrost operation it is safe to leave products inside the machine.

ROLLIN BLAST CHILLERS WITH STORAGE POD

On roll-in chillers fitted with storage refrigeration pods, the roll-in blast chiller will function as a small cold storage room when the chiller is in store mode. A defrost will occur every six hours for 20 minutes.

When the blast facility is engaged, the storage pod will be disengaged and the main compressor and main evaporator fan will take over until the end of the blast cycle. Immediately following the blast cycle, a main defrost period will occur. When the defrost period is complete the main compressor will start up again, followed 1-2 minutes later by the main evaporator fan for a period of 10 minutes. After 10 minutes the blast chiller will revert to storage mode until the blast facility is once more engaged.

THE CONTROLS

The control panel enables the display of detailed information about the machine and its performance. If the machine is also fitted with a printer (standard on roll in machines, optional on reach in cabinets), detailed historical information can be printed out for immediate use or archived.

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1.The ‘Cabinet Temp’ display window can be used:

To show the cabinet wall temperature.

As a count up timer in probe blast.

2.The ‘Probe’ window can show:

Temperature during a blast cycle, (blank during store).

During a blast if a food probe fails it will display ‘pf’ in its own window. At the end of a blast cycle it will indicate alarm code in Probe 1 window.

3.For a timed blast, the green row of LEDs show the progress of the blast. Each LED indicates another 1/10 of the total blast time has started. When there is only approximately 50 seconds left to blast, the right hand LED will flash. For a probed blast, the green LEDs again show the blast progress, but this time each LED indicates 1/10 of the temperature excursion between the products starting temperature and the target end temperature. Cabinet temperature window also acts as a count up timer showing in minutes the duration of the probed blast.

PROGRAMMING A BLAST CHILL CYCLE:

1.Switch on the chiller at least half an hour before use.

2.Check that the chiller is operating at storage temperature.

3.Load the products to be chilled (see notes on loading).

4.By pressing button ‘1’ select the ‘Chill’ mode.

5.By pressing button ‘2’ select the desired type of blast, hard or soft.

6.By pressing button ‘3’ select the timer for the desired duration, or probed blast.

7.When you are content with your selected program press the to start the blast cycle.

8.If you are not content with your selection press the button to cancel your 1/2/3 selection.

As each selection is made, the indicator LED will illuminate to show what is chosen. Press to accept, or to cancel.

On completion of a cycle, there will be an audible alarm which will cancel automatically after 15 minutes or may

be cancelled with the button. ‘DEF’ will then be displayed in the ‘Cabinet Temp’ window of the control panel and the chiller will then revert to a store mode appropriate to the blast just completed.

During the defrost operation the temperature in the chiller will not exceed 38°F (+3°C) and it is therefore safe to leave products in the chiller during the defrost cycle.

To save time for repeated identical blast operations, the blast selections are remembered, so when 1 2 3 are pressed the selections automatically adopt the previous settings on the first push. So the repeat a blast, just push 1 2 3 .

ALARM AND WARNING LEVELS

For the following alarm and warning conditions, an audible alarm will be activated and a warning ticket will be printed if the printer is fitted. A faulty sensor alarm will be initiated if a sensor fault condition is detected. If there is an alarm condition, probe 1 window will display an alarm number a0 to a7 during store (*see alarm table at the top of the next page), but will show the probe temperature during blast.

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7-SEG DISPLAY	ALARM CONDITION
a0	Air on sensor failure
a1	Wall sensor failure
a2	Fin sensor failure
a3	Food probe 1 failure
a4	Food probe 2 failure
a5	Food probe 3 failure
a6	Spare
a7	Power cut detected

Note: If a wall sensor fails it will also read -50.

For each probe only one audible alarm and alarm printout is allowed to be issued each day. This is to prevent excessive paper use and noise nuisance in the event of an intermittent probe failure. However, repeated probe failures are displayed on the probe display window, (top window in the case of 3 probe panels).

To cancel the audible alarm press the button. If the alarm condition still exists the display will continue to indicate there is a fault.

THERE IS NO RE-SET FACILITY.

THE PRINTER

If fitted and “ON”, the printer is activated after each blast cycle. The printer provides hard copy historical data of cabinet performance or warning tickets to archive or act upon.

The formats available are:

Midnight Ticket (if programmed)

At midnight a ticket is automatically printed for archiving in the morning. The midnight ticket provides the following information:

Time and date of printout and cabinet number

Cabinet temperature at time of printout

A graph of cabinet temperature over the preceding 24 hours

Demand Ticket

A ticket may be requested from the control panel by holding the printer ‘On/Off’ button for 5 seconds.

This ticket provides the same information as the midnight ticket except that up to seven days of historical data are printed.

Alarm or Warning Ticket

A ticket is automatically printed if any condition is detected by the micro controller which may need attention.

The print function may be terminated by pressing the printer ‘On/Off’ button.

Mains Power Failure Ticket

If mains power fails for more than 5 seconds a ticket is automatically printed which gives the time of power failure and the time at which power is restored.

Sensor Failure Ticket

If the controller detects that one of its sensors has failed then a warning ticket will be printed.

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PRINTER SET UP

(CAUTION!!! : DO NOT CHANGE any other parameters when setting the date & time! If additional parameters are changed, there is a great possibility that the VBC Cabinet will not function properly and will void warranty!)

TIME AND DATE SET UP

A.Enter the Engineering Switch Mode by doing the following:

1.Turn control panel "off" by pressing the "standby" button.

2.Press and hold the "1" button.

3.While continuing to hold the "1" button, press and release "standby" button.

B.Press the “2” or "3" button to step through the engineering settings. When the display shows "ute", you have reached the time and date settings.

*Note: The setting functions (i.e. "ute","hr") are only displayed when the "3" button is depressed. When the button is released, the actual setting value will appear and can then be set.

●Minute (shown as "ute") Press " " to increase or " " decrease minute

●Hour (shown as "hr") Press " " to increase or " " decrease hour

●Day (shown as "day") Press " " to increase or " " decrease day

●Month (shown as "nth") Press " " to increase or " " decrease month

●Year (shown as "yr") Press " " to increase or " " decrease year

*Note: When entering the year, there could be only one character displayed. Examples are below:

1 = the year 2001

2 = the year 2002

3 = the year 2003, etc.

C.When entry is complete, press "standby" once to exit the Engineering Switch Mode. Then press "standby" again to turn on the cabinet.

D.Print demand ticket by holding printer "on/off" button for five (5) seconds. A printout will be produced to confirm new information entered.

*Special Note: If there is information entered by error, wait approximately two (2) minutes before starting the process over.

LOGGER PAPER INSTALLATION

Logger paper should be installed as shown. It is best to tear the end of a new roll at a 90 degree angle for easy installation.

Once logger paper roll has been inserted into the printer, use the “feed” button on the control panel to automatically bring paper forward.

PRINT CARTRIDGE REMOVAL & INSTALLATION

●Remove printer cover and logger paper.

●Press the end of print cartridge that calls out "PUSH" & "EJECT".

●Once cartridge is pressed at "PUSH" & "EJECT" end, simply remove cartridge from the printer.

●Place new cartridge by carefully putting at designated location.Turn

*Note: (1) If printer does not work, check the print cartridge and logger paper for proper installation. (2) Exposed print cartridge ribbon can dry out. Adjust to printable fresh ink by turning the wheel in the direction indicated by the arrow. Change out print cartridge with the spare provided if adjusting the ribbon does not work. (3) All blast chillers are shipped with a spare print cartridge and logger paper. Print cartridges and logger paper can be purchased from a local office supply store.

“Paper Installation”

“Print Cartridge Removed”

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POWER FAILURE

A power cut does not cause the loss of any accumulated historical data and no re-programming is necessary. The controller’s battery is continually charged and provides emergency back up under normal power failure conditions.

MAINTENANCE

The cabinets are fully automatic in operation. Cleaning, loading printer paper, and changing out the print cartridge is the only maintenance required. Read the following topics.

CLEANING

Exterior: The exterior of the cabinet is stainless steel and if cared for correctly will keep its ‘as new’ finish for many years. Normal day to day cleaning should be carried out with a soft cloth and soapy water. Always wipe the cabinet vertically in the same direction as the grain

in the stainless steel. Whilst stainless steel is a very strong and robust material, the stain smooth finish can be spoiled by wiping against the grain. Never use abrasive materials or cleaners, or chemical cleaners, as they can damage the surface and cause corrosion. Occasionally, the exterior should be polished with a good stainless steel polish to protect the surface.

Do not use abrasive cleaners, chemicals or scouring pads on the control panel. Clean the control panel only with a soft damp cloth. Avoid excess water on the control panel, and other areas where electrical components are fitted.

Interior: The racking can be removed for easy cleaning (see Fig 1). This should be done on a regular basis with warm water and a soft cloth, dry thoroughly afterwards. To remove the racking and shelf supports follow this procedure: First remove the shelves, then remove the shelf supports by

grasping firmly in the center and lifting slightly. Turn the shelf support towards Fig 1 the interior of the cabinet by pushing it in the center as you twist the support

through 90°. The shelf support will be released. (Note: the supports are designed to be anti-tilt and you may therefore experience some resistance at first which will be overcome with practice). When all shelves have been removed, remove the racking by lifting up and over the nylon retaining blocks.

Door Gasket

Clean the gasket weekly with warm soapy water and a soft cloth taking care not to damage it. DO NOT use a sharp knife to clean or scrape the gasket. Regularly check the gasket for any damage. Damage can be caused by striking the gasket with a sharp object such as the corner of a tray. Damaged gaskets do not seal correctly and can increase the amount of electricity consumed, seriously affecting the efficiency and performance of the cabinet.

Damaged gaskets are easily replaced. To fit a new gasket - simply pull out the old gasket and push the new gasket into the channel (gasket retainer) at the center and work along the gasket pushing it into the channel, continue in the same way on the other three sides, pushing the corners in last (see Fig 2).

Condenser Cleaning

Retainer Channel

Gasket

Fig 2

The condenser, which is part of the refrigeration unit, is sited in the unit compartment and requires cleaning, approximately 4 times per year or when the LED indicates. To clean the condenser, disconnect main power supply before starting, then brush the fins vertically with a stiff brush, taking care not to damage the fins or push dirt or dust further in and vacuum away. Remember to reconnect main power supply once finished.

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TECHNICAL SERVICE & REPLACEMENT PARTS

Victory Refrigeration strives to provide excellent customer service along with quality equipment. To help us better assist you, a serial number and/or model number must be provided when contacting the technical service or parts department. The data plate is located inside the reach-in cabinet on the right side wall. Roll-in blast chiller data plates are placed on the exterior of the back panel that supports the controller. All serial numbers are recorded and kept indefinitely.

RULES OF THUMB

Pre-chill the cabinet for thirty (30) minutes before you do first load (to remove interior residual heat).

Doubling the food thickness triples the pull-down time.

Don’t stack food and/or containers on top or alongside of each other.

Covering the food increases pull-down time by 10% - 30%.

Pull-down rate initially is about 2°F per minute and approaching final temperature is about 2 minutes per degree Fahrenheit.

Factors affecting blast chill pull-down times:

1.Entering food temperatures (the hotter the initial temperature, the longer the pull-down time).

2.Final food temperature (the colder the final temperature, the longer the pull-down time).

3.Food “thickness” (the greater the distance from geometric “core” center of food to it’s surface pull-down time).

4.Food density (the greater the density, the longer the pull-down time).

5.Food thermal conductivity (the lower the conductivity, the longer the pull-down time).

6.Food specific heats (the higher the specific heat, the longer the pull-down time).

7.Container surface area (the smaller the surface area, the longer the pull-down time).

8.Container material (metals are conductors and render a shorter pull-down than plastics which are insulators).

9.Covering material (metal preferred instead of plastic for reasons above).

10.Covering method-cover such as aluminum foil or a “stretch wrap film” placed in direct contact with food eliminates the “dead air space” between the cover and the food. Since “dead air space” is an insulator, elimination of reduction of it shortens pull-down time.

11.“Delta T” is temperature difference between the food and the blast of air. The greater the “Delta T” the quicker the pull-down time.

12.Air velocity (the greater the air velocity across the food, the faster the pull-down time).

13.Amount (weight) of food put in as compared to rated capacity of machine. Exceeding the capacity increases the pull-down time.

14.Mechanical problems (equipment not operating at full efficiency takes longer to pull down)

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