Used Ultra Low Freezer in Cold Storage

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Showing all 6 results

The Cold Truth about Freezers

Whether you buy Like New, Used, or New, scientific lab freezers are substantial investments necessary to insure compliance with storage regulations, cold storage for laboratory reagents, chemicals and experimental samples. If there’s one kind of instrument that labs of all types (such as universities, startups, biotech, clinical, and pharma) use abundantly it’s a freezer.

Freezers range in temperature from -20 deg C to – 150 deg C. Storage application and sample stability will dictate the correct freezer for you. There are a variety of freezers available such as Revco, Nor-Lake, and Fisher Scientific, Lab-line and many others that you can choose from.

Freezers can come in different sizes such as benchtop, upright or chest. They can include various options such as manual defrost, racks to accommodate boxes and other storage containers, temperature monitoring/alarm, and built in locks.

Antonio describes the optimal conditions to operate a piece of cold storage equipment, and talks about the standard -20 C freezer, plasma -40 C, ultra-low -80 C, and cryo -140 C to -196 C deg freezers for sale at BioSurplus.

Here’s a quick summary of each type freezer:

Type of Freezer

Specification Standard

  • -20 deg C
Plasma Freezer

  • -40 deg C
Ultralow

  • -70 deg C
  • -80 deg C
Cryofreezer

  • Mechanical
  • LN2
Type Benchtop, Undercounter, Upright Upright, Chest Upright, Chest Upright and Chest for Mechanical; Box for LN2
Temp Range Up to -20 deg C Up to -40 deg C Up to -86 deg C No LN2, up to -150 deg C; with LN2, up to -196 deg C
Racks Standard shelves Standard shelves, Rack for boxes Standard shelves, Rack for boxes Rack for boxes
Defrost Manual Defrost and Frost-free available. Manual defrost freezers are best used for samples that are sensitive to temperature fluctuations (i.e. enzymes) Manual Defrost Manual Defrost Manual Defrost
Liquid Nitrogen NA NA LN2 backup system option available in some units Some models require external supply of LN2 as cooling medium, some do not

Ultralows (-70 deg C and -80 deg C)

The lower temperatures of ultralow freezers provide longer term storage and stability for items such as bacterial stocks, RNA samples and other critical items in the lab with temperatures of -70 deg C, and -80 deg C.

Plasma Freezer

A -40 deg C freezer can be used for low temperature storage of general biological samples but is generally used for special samples, like blood plasma, vaccines, and test samples that have a specific storage requirement of up to -40 deg C.

Cryofreezers

Cryofreezers and cryogenic freezing provide longer term storage for critical items such as cell banks, cell lines, and tissue samples up to temperatures of -150 deg C – 196 deg C.

Comparison of Cryofreezer types

Chest Cryofreezer (mechanical) Liquid nitrogen (LN2) Cryostorage Systems
Advantages
  • Studies show that -150deg C is sufficient for long-term storage of cells
  • Uniform temperature in freezer chamber provides more stable long-term storage and increase in cell viability
  • Easier maintenance
  • No need for liquid nitrogen supply
  • Lower operational cost
  • Storage does not cause sample contamination
  • LN2 Storage System is typically less expensive
  • Traditional method of storage of cells
  • Lowest temperature of storage (-196 deg C)
  • Simple and mechanically reliable

 

Disadvantages
  • Initial cost of cryofreezer is much higher than LN2

Can present more mechanical issues than LN2 storage systems

  • Lack of temperature homogeneity in LN2 vapor phase. Studies show fluctuations between -135 deg C and -196 deg C can occur, causing loss of cell viability
  • Higher operational cost
  • Requires constant supply of liquid nitrogen
  • Risk of contamination when stored samples are submerged in liquid nitrogen

 

Moving your freezer to a new location

These simple steps and tips will keep your freezer running smoothly.

  1. Check your freezer’s compressor and determine if it needs to be secured before moving.
  2. Disconnect your unit’s condensate vaporizer bracket if it looks like it will be in the way.
  3. Place the unit on a handcart or appliance dolly and keep it as vertical as possible.
  4. Once you place the freezer in its location, allow it to remain in a vertical position for 24-36 hours BEFORE TURNING IT ON to allow the oil to drain back to its proper location.

Freezer Maintenance

It is very important for the longevity of your freezer to do periodic cleaning and maintenance of your freezers. This will ensure the integrity of the contents in your freezer.

Here are some freezer maintenance basics:

  1. Don’t crowd the freezer. Freezers require free air access! Keep a minimum of 4 inches at the top, rear and sides.
  2. Clean the interior of the cabinets on a regular basis to remove spills and odors that may have occurred while in use. Much like with your freezer at home, this will allow you throw out anything that is outdated or rotting and will free up space for new experiments.
  3. Remove dust from the condenser. Brush out the dust and vacuum! Loosen any obstruction to prevent temperature fluctuations, compressor damage and loss of content.
  4. Defrost freezer to prevent ice build-up around door seals.

Preventive Maintenance Plan

If you are looking for additional piece of mind to ensure the safety of your critical samples, BioSurplus offers a cost-effective cold storage preventative maintenance plan. Here’s a PM checklist of what is offered:

  • Remove plenums and check heaters, circulators and condition of refrigeration coils. Also, check and reseal any openings through rear wall for piping, tubing and electrical wiring pass-thru’s.
  • Check condition and location of all sensors.
  • Ensure all drains and drain tubing are clear.
  • Check all electrical connections and tighten wiring.
  • Check all electrical components for proper resistance and continuity.
  • Check input voltages, fuses and amperages of all components.
  • Check condition and operation of all SSR’s and relays.
  • Remove rear access panels and inspect refrigeration solenoids, capillaries, tubing and components.
  • Adjust refrigerant lines and capillaries from chaffing.
  • Inspect compressors oil levels, refrigerant charges, temperatures and pressures.
  • Check refrigerant systems for leaks.
  • Confirm operation of solenoids and adjustment of pressure regulators.
  • Clean condensor coils.
  • Check fans and lights.
  • Perform vibration test.
  • Perform noise level test.
  • Perform electrical tests (leakage, ground circuit resistance, and polarity), power receptacles (if any inside).
  • Inspect door gaskets, tighten & grease hinges. Remove any ice that may be blocking proper closure.